To raise or not to raise

March 13, 2006 3:06 PM

How much would it cost to raise a 900-square foot house a few feet & give it a new foundation? Looking at 1912 Craftsman in Seattle that is a good deal but would only work if we could add some space, and the attic doesn't seem tall enough to add dormers. Just looking for a rough idea of what to expect.

The basement (which is really only a 1/2 basement) is just tall enough to walk around, not tall enough to finish off. Ideally, we would dig out the other half of the basement. I have no experience with home improvement.

Additionally, I'd like to rip out the oil heater (which feeds radiators) and put in a gas furnace.

Anybody have experience doing this?

posted by _sirmissalot_ to home & garden (16 comments total)

I think he means to lift the house off its foundations, excavate the existing/new basement underneath it, and then reinstall the house on new foundations. Basically, it's like how they move historic old buildings in a lot of places, only he'll be putting it back in the same spot.
posted by LionIndex at 3:25 PM on March 13, 2006

Friends of ours recently did something similar- poor drainage had led to the original foundation subsiding, so they did some drainage work, jacked up the house, and poured new concrete to bolster up the foundation.

They now have a little drainpipe flowing into the street that produces a steady trickle of water, even when it's been weeks without rain. Our friend commented that he wishes he could bottle that water and offer it to people, since it cost him $70,000.

by the way, in the process of raising the house, all the interior walls cracked and have to be repaired...
posted by ambrosia at 3:26 PM on March 13, 2006

Retrofitting a basement doesn't necessarily require raising the house. It will be less expensive if you don't. Basically you're underpinning the existing foundation (providing a new foundation under the old) and installing a new slab floor at the new basement level. This is presuming the house has an existing crawl space.

There should be several contractors in Seattle that specialize in retrofitting basements and underpinning failing foundations. I'm guessing 75.00 a square foot, unfinished.
posted by xod at 3:33 PM on March 13, 2006

There is a great houseblog, Casa Decrepit, that chronicled a foundation replacement where many unexpected things went wrong. They said that a foundation replacement would usually cost about $130,000 (in the SF area), though CD's went higher.
posted by john m at 3:37 PM on March 13, 2006

Yes, I do mean "raise" as in "lift."

The foundation is not (necessarily) failing now. My purpose would be to give the basement enough headroom to add windows and finish it out. I've definitely seen it done in Seattle, I just don't have a clue as to how much it might cost.
posted by _sirmissalot_ at 3:57 PM on March 13, 2006

Wait--are you planning on raising the entire house to make the exisitng half basement work (by raising the ceiling height and leaving the floor where it is) and digging out under the other half of the house?
posted by LionIndex at 4:05 PM on March 13, 2006

I owned a home that had one basement wall collapse because of a water main break, therefore it was an insurance claim. The house was square in shape and was a bungalow (but not craftsman). It was built in 1922.

The process is not simple, and it's expensive. It's more involved than any do-it-yourself project, certainly.

Things to consider:
It's like a house move. You have to cut away anything connecting the basement walls or floor to the house. That means electrical, steam piping, and water. And the steam piping most likely has an asbestos wrap on it - mine did.

Anything that penetrates the sides of the house and goes down to the basement has to be cut, as well. We pitched all the old stuff, and ran all new "infrastructure" in the basement. Some of that was spliced back into existing services (like the sanitary vent, for example), other stuff was totally replaced (like electrical). The house wasn't livable throughout the process.

Cost: When all was said and done, about $60k went into it - almost half the cost of the house itself.

The result? New wiring and electrical service, dry floors and walls, and a much higher ceiling. New, quiet water in nice, clean copper pipe. We had some plaster cracks six months later because of settling.

If I may suggest, I'd expand outward or upward, not downward. It's a whole lot easier to do. It also appreciates more in value than digging down - at least, in my case, digging down was a "repair", not an expansion. And in my case, the cost of the new foundation wasn't recouped in the sale of the house - if I had paid out of pocket, I would have lost a lot of money on the sale of the house.

I also suggest replacing the boiler with a gas fired one, keeping the radiators, and installing ceiling fans for air circulation. Radiant heat (especially steam) is wonderful, and installing new forced air in an old home is very invasive to the walls, the ceilings, and the floors. It's a craftsman. It's supposed to have radiators!

And you should consult a good home inspector, and a good contractor before you go any further.
posted by disclaimer at 4:16 PM on March 13, 2006

I had a guy give me an estimate for something similar up here in Maine. He uses hydraulic lifts, and his estimate for the up & down was around 20 K for a 24 x 40 2 story. A chimney would have added to that figure. Also, keep in mind that you will need plumbing and electrical work done at the same time. Once it is up in the air...the foundation is easy to do, and should be the same amount as a normal job in your area. They might try to add a nuisance fee, but it should not be to much more than any other foundation. YMMV
posted by lobstah at 4:21 PM on March 13, 2006

My parents did this in about 1988. The contractors put big steel I-beams under the length of the house, and under those, placed oversized car jacks (well, they did the same thing) at ~15 foot intervals around the house. Then they walked around and around, giving each one a pump. When they had it about 5 feet up, they supported the whole thing with columns of railroad ties.

It stayed this way for a few weeks, while they dug and poured a foundation (concrete and cinder blocks) and then they put it back down. No basements here in california; just a foundation.

It was a pretty neat process. As I recall, they took out a $30k loan, 2/3rds of which they spent on all this, the rest going to a furnace, plumbing, electric, lots of new drywall, etc... (pretty much every plaster wall inside cracked.)

The house is from the same era, roughly 1915ish, wood frame, about 2000 square feet.

My parents are quite the doityourselfers, but they found a general contractor to deal with all this. I think the whole process took about 2 months.
posted by gemini at 4:25 PM on March 13, 2006

There are advantages to using oil instead of natural gas. You can rate-shop for oil providers, it's a dense store of energy, and it's buffered in an onsite tank. New oil burners are very efficient and soon you may be able to burn biodiesel.
posted by laptop_lizard at 4:58 PM on March 13, 2006

If it is not to hard to get beams into and doesn't have a ton of jogs, basically a square or rectangle, not including utility work and if the existing foundation is in good shape, around 20k maybe less.
posted by flummox at 6:01 PM on March 13, 2006

You might want to check that, with the existing foundation and with the proposed renovation, your insurance will cover you. SOmetimes banks refuse to insure certain kinds of foundations. And I recall a few years ago when a guy was having his 1912 house jacked up and it bumped into the house beside it...and was not covered by insurance.
posted by acoutu at 6:39 PM on March 13, 2006

Hmmm...could you dig out the basement instead? Just bust up the floor (if there is one), dig out two feet of dirt, and pour a new slab? I have seen this done in some old houses in my part of the world. To protect the existing foundation they only dug to within about 18" of the walls. The resulting ledge is called a "fruit ledge" because that was where the old timers stored their canned produce.
posted by LarryC at 7:48 PM on March 13, 2006

It's going to be costly, depending on the condition of the house. If it was built solid and remains solid, then it may not be too bad. But depending on the experience of the contractor, it could end up costing you extra money. For this type of work, do not go for the low bidder! Spend more up front and make sure the contractor is reputable with insurance.

Other factors that will change the price:

1. How much room will there be available for the contractor to do the work? Is the lot small with nearby homes within 10 feet?

2. Is the house on a flat grade with the surroundings or is it on a hill?

3. Any brickwork or large chimney/fireplaces on the home?

There is much more that will be involved than just creating a new foundation. You will need all new plumbing from the floor down and new gas connections. Ideally you will want a poured foundation but I think this is the SOP these days.

Unless there are some definite water or structural problems with the existin foundation, I would take disclaimers advice and raise the roof. It will be much less costly.
posted by JJ86 at 5:55 AM on March 14, 2006

I know youve ruled out the attic, but wouldn't it be cheaper and quicker to raise the roof and the roof pitch (allowing for dormers) and develop the attic than raise the whole house and develop the basement?
posted by urbanwhaleshark at 11:11 AM on March 14, 2006

Thanks for all of the advice and especially for those of you who had an idea of the cost involved. I just talked to somebody who spent over $100K doing this locally, and so I think the house is a no-go. Did I mention that shopping for a house in Seattle is a nightmare?
posted by _sirmissalot_ at 11:36 AM on March 14, 2006