Adding on to a House

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Building a wall ro create an extra bedroom
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Jun 15, 2023

My family is interested in building an extra bedroom. We have an unused open space and can easily convert it by building a straight wall with a door. We recently consulted with one contractor, but his quote seemed a high. Does anyone have any experience building a wall for a bedroom? What is the approximate/reasonable cost and do you have any recommendations? We would use the room as a guest room, mostly so that the in-laws would have privacy when they visit.

Thank you in advance for any advice.

Jun 15, 2023

To qualify as a bed room, you will need a closet. Depends on how tall the wall needs to extend to structure. It may not be as simple. At least 8k-10k.

Jun 21, 2023

It might also require a planning approval from your local jurisdiction, most of which have regulations regarding how much of a lot a building can cover. I would suspect that with the cost of a building permit, this project would be more like 15-20K and if there is any sort of planning approval required, another 5-10K. I would not advise going "permit-free" because neighbors will report new construction and there will be fines.

Jun 24, 2023

You could try a temporary wall. Not common here but common in NYC. https://streeteasy.com/blog/temporary-walls-for-apartments/

Aug 8, 2023
Basement / foundation - adding 1200 sq ft to our house
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Oct 6, 2022

We are fortunate enough to buy a house in RockRidge in Oakland a couple of years ago. The house needed substantial amount of work, most of which we've completed. One big project remains, which is redoing our foundation / basement, digging a couple of feet, and making that space livable, essentially adding 1,200 sq. ft. to the house. Before we bought the house, we had a couple of contractors walk through who gave us general round quotes (the quote was roughly $500/sq ft). I recognize that prices have gone up in the last two years (though lumber prices are actually back down to 2019 levels after more than doubling in 2020/2021) - but now the same contractor is quoting me $900/sq ft - $1,000/sq ftand the actual size of the space is bigger than we eye-balled during that first walk through (now we have drawings done / permits pulled, etc.). This doubles the initial estimate - which we can't afford. We are thinking of perhaps using two contractors: 1 for the foundation / basement dig out and one for the framing / finishing (so that we don't have to pay the overhead on the first part of the work to the overall contractor). Has anyone done that? Also, what is the overhead these days (my contractor is proposing 20% which seems high). If you have done similar work, do you have any recommendations for contractors who handle these types of bigger projects? Many thanks.

Oct 6, 2022

I can’t speak to the foundation questions but when we did a remodel in 2018 our contractor charged 20% overhead which seemed standard.
Good luck with your project!

Oct 12, 2022

I used Alameda Structural and remain very happy with the new foundation/basement in my 99YO bungalow not far from where you live. George Walton is the owner who's very experienced and told me he'd do the job in 6 weeks and completed it in 4! I spoke to a foundation contractor that used to work for George before he started his own company (smaller jobs) and he told be to request José as the foreman (said he trained him). José is wonderful. I highly recommend them, money well spent. Good luck!

Oct 13, 2022

We have gotten 4 quotes on a large project (including foundation and excavation) ranging from low $500s to upper $600s, including the overhead which ranges from 10-17%. We haven't done any work yet, but I would try to get additional quotes before going down the separate contractors route - leaves too much room for finger-pointing if something goes wrong.

Oct 15, 2022
House Lifting?
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Feb 24, 2022

Our house has an almost-legal hight finished basement that we'd like to bring to legal height to create some additional bedroom and living space. We'll have to dig down or lift the house about a foot to do it — does anyone have any contractor recommendations for a project like this? Thank You!

Feb 24, 2022

We just completed a similar project, with close to a year each of design, permitting, and construction. We chose to lift rather than dig down because going down was just as expensive, provided less desirable space, and seemed to risk water damage in the long term. It's a huge project, even with an existing basement. I suggest you find an architect or designer whose work you like first, since that may dictate the contractor. We worked with Lyn Alhorn. Friends who lifted worked with Jason Kaldis.

Mar 2, 2022

We just finished the very same project that you are describing, and we couldn't be happier with our contractor. We interviewed at least 8 contractors and we ended up with Counterforce http://www.counterforceinc.com They don't have a heavy on-line presence, but they are booked in advance because of the work that they do (We waited for them for 6 months). We liked their work so much, that we ended up retaining them as the general contractor of the project and in charge of the subcontractors (plumber, electrician, tiler, etc.). You can contact James Ferguson at 510.283.4337. Cristina

Mar 2, 2022
Adding a new bathroom and property tax reassement
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Aug 29, 2021

We live in a small house in Albany with one bathroom. We need to add one bathroom eventually, and we have a small dead space in or house in which we can put the new bathroom. I want to check if anyone just added a new bathroom recently. Cost, GC, etc. We are fine with adding one with shower. Also, want to check how that impact property tax re-assement. It's my main concern, because I feel our property tax is already high, and our base number (with minimum yearly increase) is using our house price from 2018. TIA.

Aug 29, 2021

No direct recommendations to meet your need. But would invite you to advocate with Nancy Skinner and local officials to upzone the Bay Area/legalize housing construction. Increased ==> Increased # taxable parcels ==> decreased per-parcel tax revenue needed

Aug 31, 2021

Your property taxes will most definitely increase, if you do the job with permits - any time a permit is pulled, that information goes to the County, and your home value is re-assessed. Depending on the scope of the job (and your comfort level), you could possibly have the job done without permits. Some contractors will refuse to do the work without permits though. Doing construction with permits means your property taxes will go up.

Aug 31, 2021

When you add on to a house, only the new added space is reassessed at market rate, the rest of the house remains at the current tax rate. I'm not sure if the same is true when you add a bathroom to an existing space. But even if you were reassessed on a new bathroom it most likely would not dramatically impact your total property tax bill. But you can always call the Assessor's office and ask.

Sep 1, 2021

We live in Oakland. Our house was assed originally at about $500K. We converted a kind of basement crawlspace area to a bedroom and a new bathroom, all permitted. The new assessment put the house at about $600K. Over the years it has crept up to about $680k and our property tax is based on this. We also made other improvements without permits - updated the kitchen and other bathroom, painted the exterior, and eventually converted the garage to a playroom. We have had it appraised a couple of times for refis and so on, and it is now valued at $1.45M. Local realtors have said it may sell for $1.6M. I think the "market value" for your house (which is just a guess until it actually sells) has nothing to do with what the assessment or what the city believes it's worth. I think there must be laws governing how much the tax can be increased before you sell the house. At the point of sale, of course the new tax is based on sale price. I know people who did masses of improvements, all permitted, and the city still values the house at much less. I agree with the person who suggested you call the Assessors office. They can answer a general question and you won't be putting yourself at risk.

Sep 8, 2021
Berkeley Home Expansion for Dummies
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Feb 2, 2021

Hi all, we are contemplating expanding our Berkeley hillside home to add ground-level bedroom, bathroom and (attached or detached) plus room. The things driving this are very time-sensitive and I’m wondering what I should know about the process before we launch it so as to make it as speedy and efficient (for Berkeley) as possible. What we have so far: a basic set of plans by an architect relative not licensed in Berkeley. Aside from speed, I’m also curious about any local quirks or pitfalls of this process worth knowing about, and how it may have been affected by Covid and the economy.

One further consideration: we have a difficult neighbor.

I would welcome your thoughts and experience, especially if recent.

Thanks!

Bursting At The Seams

Feb 2, 2021

Hi I'm not an expert but from my experience with recent construction on my home, getting permits in Berkeley is an arduous and slow process. It is even slower now because of COVID-19. It can easily take 6 months + just to get the permits to start construction (in my own experience and based on what I've heard from others). If you want to get things rolling, I suggest talking to a local architect who has plenty of experience with Berkeley permitting. They can review your plans to make sure comply with your home's zoning requirements and put together a plan set that complies as much as possible other berkeley requirements. They can also shepard it through the permitting process. Things that you might want to ask the architect about are getting a survey asap and any other consultants that are required such as structural engineers etc. Everyone in construction and construction-adjacent businesses is busy right now - it can be hard to find people who have availability on your timeline so this can end up being another source of delay. Once you have a clear idea of the plan, it will be a good idea to get a contractor to get on their calendar well in advance to try to avoid delays in starting construction. Good luck! (And sounds like congratulations are also in order!?!)

Feb 3, 2021

I have heard that getting permits for ADUs is really fast. You may want to add a tiny kitchen.

Feb 3, 2021

Hi there, we're almost finishing an addition in Berkeley. We used an architect with limited experience and it showed during the entire process. (I believe we interviewed 5 architects). It took longer (it was more affordable) and we had to submit revisions and further studies until it was ready to break ground. In summary, it took 2 years until we started the project. Covid has been hard because the planning office is not open, you cannot go and check with the inspectors, and you depend on the city employees to get back to you; however, we can't complain because they've been diligent and there have not been any delays because of them. Pitfalls: we had to hire a soil engineer and redesign the foundation. That cause a delay in the project when it was underway (we lived in the house during construction). My only tip, get a great contractor that knows Berkeley. That will be helpful. Take your time on this. We interviewed/contacted 7 or 8 contractors, and we couldn't be happier with our choice. Regarding the "difficult neighbor", people do not like changes. I had to ask for signatures from my neighbors, and all of them but one signed the "no objection" when I knocked at their doors. This one neighbor asked for a specific meeting and she made tons of "intrusive" questions, but I was able to understand her concern (new windows and eventual shade on her property) that were addressed in our meeting. Good luck!

Feb 3, 2021

Hello~

Architect in El Cerrito Hills here.

You don't need a licensed architect for permits. Your contractor can submit permits for you. I would start vetting contractors right away. It is SUPER important to hire a qualified contractor to make sure the project runs smoothly. Another thing to note- because of Covid, there are considerably longer lead times for made-to-order materials like tile, plumbing fixtures, lighting etc. If you are buying off the shelf items, this is not an issue.

As soon as permit drawings and contractor is lined up, submit permits right away. Permit review can take longer than usual as building departments are backed up.

I wouldn't be too worried about the neighbor- as long as you have an approved permit and limit construction noise to permitted hours, you should be fine.

Good luck!

Feb 3, 2021

You need an experienced contractor who understands Berkeley permitting. You will probably also need a structural engineer involved. It's no trivial matter to make these kinds of changes to a home in the hills. There are very strict rules in Berkeley around fire safety, setbacks from neighbors and from the street. Don't do any more planning on your addition until you have spoken with a contractor who has experience with Berkeley permitting rules. Look for reviews on BPN or drive around and see what contractors are working on neighbors' projects. You want someone who knows the code and can tell you what kinds of changes you'll have to make to get your existing design approved, and how much that would cost. Also read up on ADU's. It's much easier to get permits for an ADU than an addition. For example, some setbacks and height restrictions that apply to an addition don't apply to an ADU. An ADU can be either attached or detached, but it has to be its own independent living space, so it needs minimal cooking facilities.

We live in the lower hills in Berkeley and since Covid began, we, or rather our architects, have investigated permits for two different projects: an ADU, which we have put on hold, and a driveway/retaining wall project which we'll start on soon. It's the architect who usually checks in with the city during the design phase if there are questions about what is and isn't allowed. And then the contractor will probably be the one who is pulling the actual permits once work starts. Our experience: Back in March, everything was shut down and the city was slow to respond. Our ADU's design was on pause for a month, waiting to hear back from the city. But they soon figured out how to work efficiently in email, and things have gone really smoothly since then. On our other project, the driveway/retaining wall project, a different architect (who has also done many projects in Berkeley) finished the design at the end of December. There was about a week of email conversations between her and city planners to refine setbacks and other restrictions. The city allowed a couple of special exceptions for our project. Now, because of the retaining wall, an engineering firm has to make a report and recommendations, and this has taken the longest. Apparently engineers are very busy right now. Once that report is done, it's just a matter of the actual build. So, my takeaway is, if your design was created with the regulations in mind, the permitting should not be too onerous.

Good luck with your project!

Feb 3, 2021

You said you’re on a time sensitive schedule and you have a difficult neighbo. That neighbor will mostly object to your plans. Have you talked to your other neighbors about your plans? If not you might realize you have other difficult neighbors. Difficult neighbors can object to your plans and add years to get your development done. It can be a long and frustrating time consuming process to do development in Berkeley with objecting neighbors even with an approved permit.

Feb 3, 2021

If you can design it to fit within the ADU (accessory dwelling unit) rules, that would guarantee quick approval with no ability for your neighbor to interfere. https://www.cityofberkeley.info/Planning_and_Development/Home/New_Acces…

Assuming you can't use the ADU rules, you may end up need to request an AUP (administrative use permit). Common things that trigger an AUP requirement including.
1. Residential additions that exceed the maximum district height limit for additions (14', 16' or 18', depending on Zoning District)
2. Residential additions that exceed 600 s.f. or 15% of the lot area
3. Alterations to portions of a building within a required setback
4. Addition of a 5th (or greater) bedroom to a *parcel* in certain zoning districts (includes most of the hills).

The AUP process is expensive, slow, and subject to further delay by motivated opposing neighbors. The City will abuse state law and drag out the process. However, assuming you're not doing anything egregious, the City does actually tend to approve these kinds of small projects. But be prepared for them to debate where your windows go, how big the addition is, what color your walls are, whether you have vegetation in certain areas, and all sorts of other things the City is stretching the law to regulate. And your motivated opposing neighbor can pay like $200 to drag it out even longer and force a public hearing.

Feb 10, 2021

Definitely consider configuring this as an ADU or, if possible, Junior ADU.
That way when the kids move out, you can create a housing unit and have some income from it.
The ADU may also speed your permit approval process, and the good thing is your permit is "by right", which means no Administrative Use Permit (AUP) or neighbor review.

Your question is too open ended to answer in full. The process in Berkeley is indeed "full of process".

I do ADU and Junior ADU consulting, and each job brings a City challenges. There's no one right answer.

Being open with and involving your neighbor is still highly recommended.

Feb 16, 2021
Moving vs. Improving/Adding a Second Story
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Oct 3, 2020

We bought a house a couple of years ago in Oakland when we were scared that if we didn't pull the trigger we'd get priced out, and now we've realized we made a lot of compromises that are making our lives a little more difficult! The house is on a beautiful lot, we have a great neighborhood and location, and we've already put significant money into structural fixes and other improvements, but it's small for our needs, and if we have another kid or need to have our parents come live with us (both very real possibilities) then we'll have to either move or expand.

Anyone planned a major home addition recently or done the cost/benefit analysis for move vs. addition? With house prices so high and inventory low we're wondering if an addition makes more sense, where we could put an in law unit in the basement and do everything exactly how we want, but we also wonder if prices might drop and it would make more sense to wait a bit and just move. No one has a crystal ball but would love to hear thought processes, especially for anyone who's been going through this same decision recently.

Oct 3, 2020

Shockingly we bought a house that wasn't perfect a few years ago. But the cost of moving seemed excessive when we factored in transfer tax, sales commission, cost to hire movers, cost to make make the house presentable, etc... We talked to an architect about building an ADU. One thing he said that stuck in my mind is that a rule of thumb for cost to build would be around $600/sqft. That was a year ago. Homes around us go for more than $600/sqft so it seems like doing an addition made more sense than moving. The reality is that I don't know too many people who are in their perfect house. Everybody has had to compromise.

Oct 6, 2020

As a retired architect, I can tell you the current political climate is very hospitable to new ADU's (accessory dwelling units), and I hear contractors are eager to build them. I've never seen this before, and suspect the timeframe is limited.

One thing to keep in mind when doing the cost benefit analysis of moving versus remodeling/adding, is that in staying put, your property tax basis remains intact (it will be adjusted for the improvements, but the basis remains intact). If you move, the property tax for the new home with begin at the current baseline. This is the deciding factor that keeps many Californians in their homes.

Oct 7, 2020

Hi! We went through a similar analysis. The decision you will be making in highly complicated and dependent on a few things. Would love to speak offline with you about our situation - we went through a complete remodel of a home we purchase recently. Private message me for contact info.

Oct 7, 2020

We are in a very similiar position (great view and yard, walkable to a great elementary school, barely fits now). We did get some bids for converting our unfinished basement space into essentially in in-law suite and were shocked at the estimates. We got quotes from middle end contractor and design/build firms that all came in at $200,000+ for finishing a roughly 300 sq space that is half at ground level. Those are actually more expensive than putting an ADU in our backyard (those estimates we got ranged from $150,000-$200,000. I can't tell you what makes sense for your family but I can share our decision making process. We have decided to wait for a year and see how we feel and what the market is like. If we really love the house and it would cost more than $300,000 to move to the house we need (increased purchase price, commission etc), we'll do the remodel. If not, we'll move. I've done a major kitchen remodel before and it was horrible to live through, so personally I'm willing to pay for NOT having to live through an even longer remodel (we were told it would take 6 months of actual construction).

Oct 7, 2020

We converted our 2/1 to a 5/3 about 3 years ago. It was a fixer when we bought it, so we knew we'd have to do major work including the foundation.

You like your lot and your neighborhood, if you are in an area with good resale/home value I would seriously consider staying and investing in expanding. It will only increase your home/resale value. If however, you are so-so about your house and hood, you might want to consider a move. Just know that it is an insanely crazy time to buy right now, with prices high (and rates low) and lots of competition.

While you are right that we don't know what will happen next, all indicators point to a slowing but no significant drop in the Bay Area RE market.....good luck!

Oct 7, 2020

You would probably be better off moving. Adding a second story starts with the questions of can you do it? Will the city allow it, will the neighbors and can you existing house support a second story. Then you have the issue of finding a contractor. And an even harder time finding a good one. Will you be living in the house during the construction? Probably not. So now you are going to have to live someplace else for 6 months to a year. Then will you house fit in with the rest of your house and the other houses in the neighborhood? Will your house be double the sq ft of all of the other houses? So your house no longer fits in?

With covid prices in the East Bay have remained strong. I would have thought prices would have dropped with covid and end of summer but that's not what's happening. I don't get it, but people are paying over asking. Could it be because interest rates are so low? You will probably never see interest rates this low in your lifetime ever again.

If times were different I might say add the second story. But the way things are right now in the Bay Area I would move.

Hope this helps.

Oct 7, 2020

Also consider adding out, rather than up (or out with two stories) if you have enough yard. It can be somewhat cheaper per sq. foot because the addition gets its own foundation, rather than potentially having to beef up the existing one. Our property slopes down in the back; we added a split level to the back, and love it. It also looks much less imposing from the sidewalk that just going straight up would have been. (From the sidewalk, you can't even tell it's two stories).

Oct 14, 2020

One other thing to consider - the costs for temporary housing during the (probably many) months when the work is being done. When we built off the back, we were able to stay in the house for all but a couple of days, so that saved both money and hassle.

Oct 14, 2020

We’re going through this exact same thing. We’re on a huge lot with a small house and thought that adding another bedroom and bath would solve the problem with our 2/1. We converted the garage a few years ago so my daughter would have her own room since she was sharing a room with her brother. We’ve met with 4 architects now and all of their estimates have been around $300-400k for the add on, which seems ridiculous to me. A contractor friend told me that construction materials have doubled during lockdown, but also everyone wants to do home improvements now so everything is much more expensive. So do we move or just suck it up and do the add-on? Every house we’ve looked has sold for at least $400k over asking price and then there’s the huge jump in property taxes to think about. We’re probably going with the add-on, once I can get over the sticker shock.

Oct 27, 2020
Cost of home addition
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Mar 2, 2019

We know that at some point we will need to add onto our 860 square foot 2 bedroom 1 bathroom house. We are a family of four and while our kids are young, we think that as they get older they will need their own space, especially since they are different genders.

We recently completed a 300 square foot in law cottage that cost about $115,000 total (a prefab build) but are wondering about the cost of building up, lifting the house and building underneath, or building out. My hope is to be able to either build up or lift the house to be able to take advantage of the Golden Gate Bridge views in a way we couldn’t building out unless we went out and up. At the very least, we would like to add another bedroom and bathroom, probably a master suite.

Has anyone done a similar project recently and how much did it cost? Any other tips? We are probably a few years away from actually doing this but need to get our ducks in a row.

Mar 2, 2019

Thanks for sharing about your experience. There are a lot of factors that go into determining the costs of doing additions. I recommend speaking with at least three contractors.

Mar 6, 2019

The short answer would be to budget $500/square foot.

We recently build a second storey and renovated the existing kitchen and bath in our 2/1 in Albany. It ended up around the above-quoted number, though of course details will matter. In terms of your options, building out and up is a cost-effective way to achieve what you want. We've seen 3 homes in our area where they extended the kitchen out to create an open kitchen/family area, with stairs leading up to a master suite. This way you get air and views, without having to significantly modify and reinforce your existing structure and foundation (that's what we had to do for a strictly on-top addition). I've heard arguments for lifting up and building under, but unless the lower storey is still well above grade, it's likely to be darker/basement-ish, which I find unappealing. Building out would also (typically) allow you to stay in your home during construction, which could save $10-15k on rent. You lose yard space, of course, which is the downside.

For more specific pricing you'd need (at the least) a floor plan sketch, which many architects will do for minimum cost. There are several recommendations here on BPN, my only tip is to choose someone local (who knows your city permitting quirks). Good luck!

Mar 6, 2019

In our experience, building up will cost you substantially more than building out - and depending on your neighborhood you may have to have to go through an additionally approval process if you will potentially block another's view by building up. The costs will depend on so many things, will you lift up or build up (i.e. will you keep your existing roof or need a new one - $50k alone) will you need to reinforce or actually replace your foundation, how much square footage you want to add, whether you hire a design/build or a GC or manage it yourself - the costs could vary by over 100k - with your total costs being between 200-400k or more. Definitely MUCH more complicated than a pre-fab cottage in your yard, but it can be done with patience and the right planning - good luck!

Mar 6, 2019
Adding a 2nd story addition or lifting house
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Jul 9, 2018

I've read a few posts about people looking for suggestions about remodeling or moving due to the need for more space. I have a few questions that I'm hoping a few people might have answers for.

1. Has anyone added a partial second story (600-800 sq ft) to a Craftsman Bungalow? How much did it cost? I know every job is different but this can help me better understand how much it might set me back. I'm looking to add on 2 kid bedrooms, full bathroom, 2nd living room.

1a. How long did your project take?
1b. Would you recommend the group who made your project happen? If so, who did you use?

2. Has anyone had their house lifted to add a new first floor? How much did this cost? Our house had already been retrofitted but if it's more cost effective to lift the goose I don't want to rule it out.

2a. How long did your project take?
2b. Would you recommend the group who made your project happen? If so, who did you use?

Jul 9, 2018

We added a 2nd story (but only about 500-600 sq feet) master bedroom/bath and nursery to our craftsman in Rockridge 2 years ago (we ended up selling it and moving back to SF). Pics are here to see the end result (added the staircase towards the back of the home) http://www.5350bryantave.com/.  It took about 6 months and was extensive (couldn't live there for most of it). We used Jarvis Architects and Ryan Campbell Construction - couldn't recommend both more highly. The entire project cost approximately $350K for us and given the cost/sq foot in the area it was more than worth it. Happy to chat more if you'd like.

Jul 11, 2018

My coworker added 2nd floor in Albany. Another 500 SF approx. you can't really get price/SF since its not as simple as building it from scratch. As my understanding she spent almost 300K. She got a contractor to build frame of 2nd floor, adding foundation footing, and she has different trades contractor for plaster, plumbing, electrical. She also changed all her plumbing pipes to pvc and improve sother misc. stuff. Hopefully, you can get the ballpark number from it. Good luck!

Jul 11, 2018

Hi! We just got permitted and are breaking ground this week on a house lift. I’d be happy to talk about our experience so far. Feel free to give me a call in the evenings or weekends. 530-559-5221

Good luck!!

Stephanie

Jul 11, 2018

I am an architect and have been doing these types of projects for many years in the East Bay, so I will see if I can answer your questions.

1. Cost of adding 600sf - 800sf on the second floor- prices have gone up dramatically in the last few years. Currently, I would estimate between $600-$800/sf for the addition. This amount includes the work you have to do on the main and foundation level to access it and support it (i.e. adding stairs, shear walls, upgrading or replacing the foundation, upgrading the electrical and mechanical systems, etc.). Costs are dependent on the soil and site conditions, extent of remodeling required on the main level, quality of finishes, etc.

2. Construction normally takes between 7 - 9 months for a project of this size.

3. Lifting the whole house and building a new ground level addition equal in size to your existing house, would be much more expensive. This requires a much larger addition (I'm assuming your house is larger than 800sf and is most likely located on a flat site?) and would require the existing house to be remodeled, since you would most likely want to have the bedrooms on the second floor and have the kitchen/living/dining on the new ground floor. The cost per square foot would be similar but the overall project is much larger than the first option.

4. This type of project would most likely take 8-12 months to construct.

Feel free to contact me if you want more information.

Kathy Rogers,

Sogno Design Group

Jul 11, 2018

We added a second story to our house in Albany in 2016-2017. We already have a basement and therefore did not look into lifting the house. It took years before we felt like we understood the options and how they translated to final costs. From my research, I can tell you there is a huge range homeowners pay for remodeling services including second stories. The type of finishings you choose (floors, tile, cabinetry) impacts the total cost, but just as important is who you hire and when you build.

Jul 16, 2018
Experience adding a level to a house
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Feb 17, 2018

hi,

We just had our first child and are quickly realizing how much smaller our house feels. We’ve been trying to figure out if we should sell our house and buy a larger one. We would have to spend a considerable amount to do this. And real estate, as everyone knows, is crazy now. We see more value in keeping our house - which is in an “up and coming” area - and adding on to it. We could add to the back but adding another level would give us the most space. Looking for anyone with experience in adding a level / overall guidance would be much appreciated!

Feb 17, 2018

we just started looking into this process and are still meeting with design/build firms. but just letting you know it's so much more expensive than we thought it would be. we're currently 3bed/2bath at 1080sqft and ideally, want to add 500-750 sqft in a 2nd story. it's about $500k which is SO much more than we thought (a friend built their house from scratch for 500k in the south bay). we may end up doing a staged approach where we just extend the first floor and do the foundation work for the second story and then in a few years decide if we want to invest the rest or sell the house.

Feb 21, 2018

We are in the throes of this same decision process. What we've learned so far: 2 different architects and a contractor have told us that adding on at ground level is MUCH simpler than going up, because you don't have to worry about retrofitting the foundation for more weight and finding a place for a stairwell in your existing floor plan. If your existing yard is not postage-stamp sized, might be worth evaluating if you have space to add on at ground level. The other thing we did was contact our realtor and ask him the "move or add on" question -- he says that he rarely advises people to move if their only goal is more space, because moving is expensive and if you like your existing house and neighborhood you'll probably be happier just staying put, especially if you've already put a lot of work into your existing house (we've redone both bathrooms, new roof, new windows, etc., so the idea of having to do all that stuff again on top of a bigger mortgage and learning a new neighborhood just feels like a nightmare :-p). Will definitely be following to see the advice you get, as we're not much further along in the process than you are :) Good luck!

Feb 21, 2018

We were in the same boat as you last year and decided to stay and add to our existing home. In addition to the financial calculations, our decision was swayed by the fact that we love our home and are attached to it, it is very near the elementary school, and we know and like our neighbors. You can't put a value on these things.

See my post here for advice based on our experience so far: https://www.berkeleyparentsnetwork.org/questions/where-begin-major-home…

For your particular situation, going back and up could be a great solution that's really popular in our neighborhood. A typical addition is a family room connected to the kitchen at the back, and stairs going up to 1-2 bedrooms above. An advantage of this design is that you may not have to reinforce the foundation of your existing structure - a huge cost saving. A good architect will be able to come up the best space plan to maximize usability and minimize cost. Good luck!

Feb 21, 2018
Where to begin with a major home remodel/addition?
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Feb 3, 2018

Hey BPN'ers. We're thinking of adding a second story to our 1100sf house in Oakland. What are the first steps? What can we expect? Who can you recommend?

Thanks!

Feb 3, 2018

We are about 75% through an addition/remodel of our home. Here's what I'd suggest based on our experience so far -- start with a local contractor or contractor/architect duo who know the local code and requirements. Think about your space plan for the addition, whether major upgrades to the existing foundation, structural, electrical, HVAC, plumbing would be needed. Ask them for a rough estimate of what the whole project would cost - expect a number around $500 per sf. At this point, you decide whether you want to proceed... I'm assuming you'll also evaluate whether it's easier to simply sell and move.

If you decide to go forward, you have to start drawing up the detailed plans for permitting. Secure the finances, and a loan/refi if that's required. Plan for how you'll live through the construction (stay or move out). Once construction begins, you should expect to have to be very involved (it's your home after all). You'll need a work schedule that's flexible enough to allow meetings with various contractors/tradesmen between 9-5. Expect your weekend to be completely taken over by design/purchase decisions. Expect at least one or two major 'surprises' that will require additional work/money to resolve. Expect to be at least 10% over your initial budget. Try to plan for relief (small vacations, help with childcare from family, etc) to keep the stress/anticipation from taking too much of a toll.

I'm sure you'll find many many specific recommendations from others on this forum. Whoever you end up selecting, make sure they have local knowledge, and be sure you can trust them with your home (even if that costs 5% more). Good luck!!

Feb 7, 2018
Can we add a sunroom and live in it like a bedroom?
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Dec 13, 2017

We need one more bedroom but really don't want to do permits and the cost of an actual room addition. We were told that sunrooms don't need permits and that they can be insulated so they are warm. My question is, do any of you have sunrooms you've used as a bedroom? Are they too cold? Is mold an issue? What are we not considering if we go this route?

Also, does anyone have cost estimates to adding a sunroom, and or adding a spare bedroom? Would just jut into the yard. There's plenty of space back there.

Dec 13, 2017

Unfortunately you got some misinformation--sunrooms do absolutely require permits, at least in cities in this area. (They may be somewhat less costly to build if they're not fully insulated, though.) We do have one that we use as living space. The major issue is that it is mostly windows and the windows are old and leaky, so it tends to be cold and sometimes damp this time of year. You'd probably be in much better shape with new windows. I'd consider whether it's worth just paying the additional cost to add a full bedroom, though, since I think you'd get that back in increased property value vs. just having a sunroom. Good luck!

Dec 20, 2017

The previous owners of our house in Danville put in a sunroom. We rarely use it and it has become storage for us but someday envision it as a game room/extra space with limitations depending on the weather outside. I would never want to use it as a bedroom because there would be way too much light and no privacy. Plus it would be too hot or too cold depending on the time of year. We were told it would cost $5000 to add heating and cooling to that room and then I believe because you’re essentially cooling a glass house in the summer, it would be expensive.

Of course it’s more expensive and takes more time and permitting to add a real bedroom space but you won’t regret it once your project is complete. You will add real value to your house when you sell it, and you will be able to enjoy it too. Don’t add a sunroom! Not worth it.

Dec 20, 2017

Sunrooms, like any other structural modification, require a permit. You can build it without one, but you'll be red-tagged if a neighbor calls the city, you'll run into problems with your insurance carrier, and you'll have to disclose non-permitted work when you sell. The cost of the permit is minor. You'll be happier if you do this.

Dec 20, 2017

Like the others have said, you definitely need a permit for building an addition whether it's a bedroom or sunroom. Any kind of building that requires electrical, framing, plumbing will require permits. Keep in mind that

building an addition with permit, it will trigger a property value reassessment by the city.

I am in the middle of doing a small addition right now in Oakland. The total square footage for the new room plus a small deck is around 200 ft. Permit fees alone were $4k, plus architecture drawings another $6k. Building cost starts at about $300 a square foot in the bay area, which includes low to mid range materials and labor.

Dec 27, 2017
Contractor for small addition on the cheap
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Jun 14, 2017

We live in the Berkeley flats in an 819 square foot, 2 bed 1 bath house - pretty small for four people. Since our kids are entering the teenage years now, we would really love for them to have their own rooms (particularly because they are different genders). So, we are looking to add on a very bare bones, simple, small, third bedroom/bathroom. We have a decent-sized yard so there is definitely room for an addition. We got a home equity line of credit for $125K and were hoping this would be enough to cover the cost of a small addition like this, especially because my husband is an architect and could draw up the plans and get all the permits. He works at a firm that does large-scale commercial projects, so he doesn't know any residential contractors. He drew up a simple plan for a small bedroom/bathroom addition and we sent it to a contractor who quoted us $250K - way more than we could afford. Can anyone recommend a contractor (or even a handyman?!) who could do a small project like this on the cheap? We can't afford anything high-end - this is bare bones! Maybe we could just leave the bathroom an empty shell and add that later when we can save up more money. And, are we unrealistic to think we could do this for $125K or less? Should we consider just putting a yurt in the backyard instead? Any recommendations or advice deeply appreciated.

Jun 14, 2017

Hi

have you looked at the new modern prefab rooms. I think it is possible in that price range last Ioomed. Google pre fab modern. It might be more complicated than advertised but much easier than a full on contractor.

Jun 21, 2017

Btw, did you see the post someone else wrote or Avava prefab ? I have no connection with them. And your husband as an architect might know them. But they said 4 to 6 weeks done. And inexpensive. And the they look visually apealing. Im super interested in pre fab houses in general because construction seems like so much work. There is probably someone on this network who has done prefab and cab guide on what to look for and referrals. Good luck to

Jun 21, 2017

We've used handyman Rob Kanter for years. He's reliable, efficient and honest. He's so knowledgeable about so many things I can't imagine a room addition would be too difficult for him. His business is called Odd Job Rob.

Jun 21, 2017

I think it would be pretty tough to do this for under $125k, even if you left the bathroom as a shell for now. Construction in the Bay Area is SO EXPENSIVE these days.

Our home is about 850sf, and we're currently renovating it. Our project also seemed pretty small: we're turning our dining room into a master bedroom, converting a closet off of it into a master bathroom, and cosmetically updating our kitchen. Excluding the architectural drawings, we're probably going to end up spending about $125k (ouch). I had the same problem as you; so many reputable contractors seem to onlywant to work on huge, whole-house renos or new builds that no one wanted to take on my relatively small project. We're working with Kasten Builders, and, overall, I'd recommend them. I wish they were more communicative and organized, but I feel like their prices are fair, their subs are good, and they're completing the work at a pretty solid pace. Feel free to PM me if you want to discuss more.

Good luck!

Jun 21, 2017

We've been trying to add on a simple room in the basement of our house (less than 400 sq feet with just a bathroom) and have been astounded at how expensive the contractor bids we've gotten are ($250 to $300). We have a budget of $180, so we haven't been able to move forward. I too wonder if there are super inexpensive contractors out there. We haven't been able to find them. I think the market right now is just crazy. Our latest idea is to get a fancy shed (they have companies that sell ready made sheds, electricity, fully insulted and very nice). Good luck!

Jun 21, 2017

You should absolutely be able to do this for $125k (but don't forget to include cost of permits!). We recently built an addition bigger than what you're describing for just a bit more than that. We were really happy with our contractor, Neal Gordon: 510-919-0739. He was honest, reliable and trustworthy, and did a good job. I recommend him!

Jun 21, 2017

I think you should call my contractor John Hearney, of Hearney Construction: 510-333-1966. I bought a small bungalow in Oakland that needed tons of work, done to code, on a truly small budget. John and his team of Carlos, Pancho and Gonzalo have really helped me so much over the years, and they do a great job. We built a small new room and new bathroom, then gutted and remodeled the kitchen (a mix of IKEA and other stuff), then gutted half the upstairs to expand and remodel a bathroom and make 2 closets more efficient. He's also built a beautiful fence and low retaining wall, outside stairs, and more. If you email me directly, I can send you a link to pics. John is a fully licensed contractor (and plumber and electrician), knows how to work with architects and structural engineers, and has built houses from zero up. He's very reasonably priced, super honest, and just a nice guy. My only caveat would be that he personally is way more focused on function than form - aesthetics are not his strength, so you need to say exactly what you want. But his team creates very polished work and has a focus on aesthetics.

Jun 22, 2017

I highly recommend Crowworks 510 520-7989. They work on both small and large projects and turned our old, worn, linoleum-clad bathroom into a beautiful, functional bathroom. We couldn't be happier with his work. Plus he and his co-worker Drew are a pleasure to work with.

Jun 28, 2017
Second story addition vs. tear down and new construction?
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Oct 12, 2016

I've been looking into second story additions for my 800 SF Berkeley cottage, and am agahst at the cost. It almost seems cheaper to do a tear-down and a new construction in its place, especially if the house doesn't have any unique historical details. What are your thoughts? Has anyone got cost estimates on either of these options?

Oct 12, 2016

As a Berkeley Realtor I have an inside perspective on these questions, and, having recently remodeled and expanded my own home (going from 1100 sf to 1600 sf), I have first-hand knowledge of what it all really costs. Most importantly, Berkeley does not allow you to simply demo what you have and start over, regardless of how architecturally significant your home may (or may not) be. So the question is, to buy a larger home or expand what you have? Now, let's do the math. The cost of adding new square footage will range from $250-$400 per square foot. People may give you much lower numbers, but don't believe them. The cost of new, expanded, or reinforced foundation footings, possible required upgrades to electrical, water, or gas service, new windows, kitchen and/or bath appliances, tile and hardwood (materials and craftsmanship) --- all of these things really add up, and are reflected in the range I gave. So, let's say you double your square footage by adding another 800 sf, and let's say you hit the middle of the range at 325x800=$260,000. Is one-half of a 1600 sf house worth $260,000? The answer is a resounding yes. There is no way you can buy a home twice as large as your current home, and pay only an additional increment of $260,000 beyond the value of your current home. And, the amount of value your current home will gain, once you double the size, will also far exceed the cost of the work. Depending on your exact location, the size of your lot, etc, the benefits of expanding can be even greater -- especially in Albany. Feel free to contact me for more advice, at HollyRoseHomes.com.

Oct 19, 2016
Buying a home that's not big enough - future additions?
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Sep 28, 2016

We are in the process of looking for a home to buy. Not surprisingly, it's turning out that homes in our price range and desired locations tend to be <1000sq ft 2 bedroom homes. Ideally we'd like more space and a 3rd bedroom as we plan to add a 2nd child in the future and have out of town family we'd like to comfortably house. One thought is that we buy a smaller 2 bedroom home we can afford and in a couple years plan to add on a couple hundred square feet and a 3rd bedroom. My question is how do we determine if the 2bdrm homes we're looking at would be a good fit for this? How do we determine if an attic could be converted in the future? Or make a subbasement useable? Do we take lot size into consideration? What other considerations are there?

Sep 28, 2016

Lot size is definitely a consideration, as it is much cheaper to add a first floor addition. The flatness of the lot is also important. There are regulations in most cities about what is allowable. You will want a contractor to look at the house before you buy it to determine the feasibility of an addition. 2nd story additions sometimes require the foundation to be shored up as well.

Oct 5, 2016

Your questions and concerns are understandable, but won't be easily addressed here. Contractors and architects can offer input on what's possible with any given home, but each home carries it's own variables - setbacks, foundation depth, neighbor trouble, zoning, etc. Expanding a home is a great idea conceptually, but in my experience, it rarely happens - with the average length of ownership at around 10 years, you're likely to move making the undertaking a questionable effort. As a realtor, I suggest two ideas: 1) find a 2 bedroom home that's at least 1200 square feet in bad shape and reconfigure it or 2) broaden your location.

Oct 5, 2016

Archived Q&A and Reviews

Questions

Construction Cost Reality Check for bare-bones addition
Does a remodel/addition really cost that much?!
Considering an addition and kitchen remodel
Estimating the cost of a 2nd story addition

Construction Cost Reality Check for bare-bones addition

April 2007

I live in a 1911 bungalow near Piedmont Avenue. We're planning on building a simple, barebones addition on the back of our house - essentially a two-story box with a family room downstairs and master bedroom/bathroom updstairs. No fancy built-ins or trim. Does anyone have recent experience with budgeting for a project like this? I've heard prices ranging from $200 to $500 per square feet. I'd like to get a rough handle of costs before sending out to get contractor bids. Shelley

Hi, My husband is a licensed general contractor--and as I was curious about your question I asked him what he thought. He replied for a truly ''barebones'' project, he estimates $250 per square foot, and the smaller the addition--the more expensive...in other words, there is inertia in the project--the larger your addition, the less cost to you per square foot. So, it would ultimately depend on your size and design. He has a masters in engineering and computer-aided design experience. Good luck with your project! Abby

Does a remodel/addition really cost that much?!

Sept 2006

We are shopping around our initial drawings from our architect to get a feel for what our remodel and addition will cost (before we spend any more $$ on drawings). We live in a small one story rancher (on a flat piece of property) and we are adding 1200 sq feet of new living space and a 440 sq ft garage. We have been quoted between $650,000-$750,000!! This is more than we paid for this shack!

Our finishes are in the mid range - Sierra Pacific wood clad windows, inexpensive tile on the kitchen floor, hardwood floors, stock cabinets, stucco outside etc. I understand that the 1.5 bathrooms and kitchen are expensive/sq foot but we did not expect the range we were given. We thought it should reasonably land around $500,000.

The other frustrating thing is that we would like to go as green as possible, but finding that you have to have bucko bucks to build green. We were quoted $19,000 alone on going solar!

Is it the market for building materials? The high cost of labor in the Bay Area? Contractors who think we can afford more b/c we live in Lamorinda? I'm looking at both big and small contractors for this job.

Has anyone else faced this type of situation on a remodel/addition. We cannot afford to move into another house within our school district nor can we afford what we are quoted to remodel. Any advice? Frustrated

I can't wait to see the responses to this one. We too had sticker shock when planning for our remodel. And we were shocked at how poorly the industry at large understands its clients, how to set and manage client expectations, and how to plan and budget based on client-set parameters. We were told to plan on $250-$500 per square foot. (!?!) So it's either ''X'' or ''2X''. Who can manage that type of a swing?

That said, our building costs are coming in around $300/sf. But please be sure they define ''square feet''. Is it just the floor space square footage? Or does it include the square footage of the roof too? What we thought was a 600 sf addition is actually closer to a 1200 sf addition because it needs a roof. (Really) Make a distinction between building costs and project costs which can include architects, engineers, permit fees, moving and living costs, etc.

I think the costs come from living in the Bay Area, a serious increase in the cost of materials, and the fact that remodeling requires connecting to existing structures which is more complicated than building from scratch. I've also heard several different methods of how architects and builders establish budgets: They determine when you bought the house and how much equity you have built in it and use that number as their target budget. OR They try and determine how much you owe on the house and estimate your yearly earnings. Then they shoot for having you leveraged between 5-10 years of your current salary.

If you pursue, start with clearly defining what is and isn't included in the price and, more importantly, define the entire process. What does each vendor require be in place for them to perform on their contract? ie: Does the architect need drawings of your current house in order to draw the remodel? (yes) Do you have those? Who does that work/pays for that work? Is it included in his/her estimate? Once you have a full picture of the whole process, you can competitive price and determine if/ how you can swing it. Good luck! I feel your pain!

A lot can have to do with location. But a good number to estimate with for cost of construction with basic finishes is $200 - $250 a sq. ft. This would not include design or permits or any new utility services. Hope this is helpful Pamela

I was told that a reasonable estimate for remodeling work should fall somewhere between $200 and $300 per sf. However, I imagine the price increases when you are going up a level, building new foundations, etc. How many people have you spoken to? Your quote seems like a lot (around $450/sf) but there may be extenuating circumstances. I also understand the cost of building materials has increased substantially in the past few years. We're in the same boat as you, but we're only adding on a little over 400 sf. It's still going to cost an arm and a leg! Remodel weary

To: Frustrated in Lamorinda/Looking for a Builder? I can relate to what you're going through. We spent the last year going through architecture/bidding/city Design Review/etc on our modest old ranch house addition in Lafayette and we're finally building now. Some of the bids we got were outrageous and we were quoted 9-12 months construction time which seemed daunting to be uprooted with 2 small kids (ours is a complete redo so we moved out.) We were so lucky to find a builder we absolutely love who is affordable, and fast (like 5 months start to finish), and he is doing some wonderful finish work like mouldings and raised ceilings that weren't even a possibility with the other bids we got. As far as the green materials, that is something we didn't dig in our heels about because we were just too close to our max. But I would be happy to talk to you more and give you his name if you'd like. Just let me know. Kristi

Considering an addition and kitchen remodel

March 2003

We are considering an addition and a kitchen remodel to our home in Lafayette. I guess i'm interested in anyones experience. From the permit process to hiring an architect/contractor, to actually living with the work being done. Also what kind of costs should be allocated to permits and drawings? Any insight/advise would be appreciated. I have checked previous recommendation and have not found what I'm looking for. Carole

You will need plans of the entire house, not just the addition. Your city wants to see engineering on even minor additions to be sure you have professionally calculated earthquake precautions.

The permit process has two stages- Planning and then Building.

Planning wants to make sure you comply with local zoning and aesthetics. After that 0-3 months, your plans go to Building for code compliance (smoke detectors, rating of insulation, etc) for a month or more.

You could spend 5-15,000 on this process. The permit fees are based on a percentage of the estimated cost of construction, which you can round down a bit. As for hiring a architect or contractor, you should feel comfortable talking with them and not feel condescended to or not listened to

Your contractor should be licensed, bonded, have workmen's compensation insurance and liability insurance. All of those protect you from responsibility for accidents that take place on your property. If you solicit multiple bids for your project, you will receive a wide range of prices. Why? First, not all contractors pay their taxes (payroll, income, business license, etc.) Why should you care? If an irritated neighbor or a building inspector (both will visit the job site regularly) stirs up trouble, your contractor may disappear and you could be left indefinitely with a home in disarray.

The other reason for a wide spread in prices is that many contractors, in learning to survive in a competitive field, have learned ways of cutting corners not visible to the homeowner. Using inferior grade wood, cheap paint, unskilled laborers, hiding mistakes are all common traits of the average contractor. 2 or 3 years out, problems arise and you will find that the average contractor will not stand behind their work.

I am presently business manager for Pearson Construction and I am proud of the way we fulfil our client's expectations while controlling costs. The primary way which we do this is by working on what is called a Time and Materials basis. That means that we have hourly rates for each grade of workman (like an architect, draftsperson or engineer) and do our honest day's work for an honest day's pay. This is particularly advantageous because clients almost always change their minds once or thrice during a project of any magnitude; this arrangement allows you do that without incurring possibly extravagant change orders which you WILL incur on a bidded job.

I'd be happy to discuss your job with you.

Evan

Estimating the cost of a 2nd story addition

April 2002

We are considering adding a second story to our home and would like to know how much it would cost us. What is the best way to find this out? I'm not sure who to contact for this, I know our foundation would need to be evaluated. How close are estimates to the actual price? Any advice would be greatly appreciated. Jackie

We are still considering, after1 year, whether to add a 2nd story or move. I would suggest you talk with a architect and contractor TOGETHER and talk to several people. We thought we knew what the cost would be for our remodel based on initial discussions with a contractor and a review of our preliminary architect plans by a contractor. When we got actual bids, when we could get them, they were 50% higher than the high end of the range we had been given after the review of our plans. This was last spring and this year seems a bit better, but be prepared. The prices per square foot are between $200 and $300. Denise N.

I'm not sure how far you've progressed with plans for the potential addition to your house. If you're still just thinking about it and don't have much drawn up yet, you might want to hire a cost consultant(someone who is disinterested in actually building it) or pay a (reliable, established) contractor to do a preliminary estimate. Even with very minimal drawings, you'd be able to get an order-of-magnitude sense of the project cost (i.e. it's going to be closer to $150,000 than $15,000 or whatever)(and unfortunately, it will, by the way, be closer to $150,000 than $15,000...) If the project seems feasible, you'd want to hire an architect to draw some plans, and then I'd strongly recommend that you get another preliminary estimate at the end of the Schematic phase of design. That way, you'd get a sense of where the budget is going before you spend a whole lot of architectural fees to get a complete construction set of drawings and then find that the project comes in over budget. The accuracy of a preliminary estimate depends on a few things: 1) the level of drawings -- obviously, the more complete the drawings, the more accurate the estimate can be; and 2) the competency of the estimator -- unfortunately, lots of the less-expensive and smaller general contractors are very good in the field and not so good in the office. You'd be well advised to apply a significant contingency to the bottom line of any preliminary estimate you're given. If the estimate is based on a few sketches and a site vist, I'd recommend adding atleast 35% as a contingency. If the drawings are more developed, the contingency gets lower (even at a construction set of documents, I always show a 10% contingency). And I think it's important to accept the overwhelming likelihood that the contingency will be spent. Just to get you started, I'd say that the addition itself would be $175/square foot as a bare minimum, plus atleast a few tens of thousands for mucking around with the disturbed finishes and reconfigurations required on the first floor (assuming the addition doesn't trigger a seismic upgrade to the whole existing structure), plus whatever work is required to the foundation. And be prepared (financially and emotionally) that even with the most competent architect and contractor and the most decisive owner, through the fault of noone but the pipe that's in the wrong place and the utterly bizarre and unanticipate way they framed the ceiling in the original house, the project will probably take longer and cost more than you thought it would. (I'm a construction cost consultant; and a general contractor. NOT trying to drum up business.) Alysson