What should I be concerned about if I replace a foundation and creat a full basement at the same time?

Asked by Shane Kibble, Willow Glen, San Jose, CA Mon Oct 22, 2007

I am a first time home buyer, and I am set on purchasing an older home with character. These homes often have small (barely usable) basements and foundations in poor condition. I see this as an opportunity. By replacing the foundation and creating a full finished basement at the same time, I can increase the living space. What are the potential issues I might face in doing this- what should I be aware of or concerned about?

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Ruthless’ answer
Ruthless, , 60558
Mon Oct 22, 2007
First, structural damage to the house, cracked plaster, un-square doors and windows, etc.

Next, price verse value. The money you spend might increase the living space for you, but it won't necessarily increase the living space for appraisal value like an addition or above grade improvements would.

Third, exterior and additional costs. If you do this, will you then have to replace any plumbing or sewer lines? Will you have to re-sod the yard after all the heavy equipment destroys it?

And last, a bit of advice I heard was, "whether you are moving a house one inch or one thousand miles, get a certified home mover to do the job." There aren't a lot of those companies and they are expensive.

My advice, buy a larger older home and forget about the basement.
3 votes
Jennifer Kre…, Home Seller, 95124
Mon Oct 22, 2007
Hi Shane,
I'm an architect in San Jose and I've had experience doing this on a few homes around here.
First, it is an expensive and timely process, but in certain areas can be well worth it. That's especially true if you are already at the maximum floor area ratio (FAR) of .45 in San Jose for your property. A full basement gives you extra square footage that is not included in that FAR calculation.
The new basement will have to comply to all of the current building codes including ceiling heights, egress (exit) wells, stairs and possibly a sump pump/sewage ejector. Also, the new basement which will be the new foundation for the house will need to have hold downs that anchor the wood structure of the home to the foundation.
As far as cost: expect to pay somewhere in the range of $100 per square foot for the unfinished basement and considerably more if you finish the basement and add a bathroom, etc.
While the foundation is being built, the house will be raised on a few steel beams. It's precarious and if a large enought earthquake happens during that time, you may lose the house. It's a real nail-biter sometimes and the house may be raised like that for three months.
Hope this helped,
Jennifer Kretschmer, AIA
Web Reference:  http://www.jkretschmer.com
2 votes
Infinity Rea…, , Saratoga, CA
Mon Oct 22, 2007
Im not sure maybe i misread the question, but i didnt see where you wanted to move the home. But if you plan on rebuilding the foundation as you say. Make sure if your set on doing it, but a house that actually already has a great amount of foundation damage. If this is the case you should get a substantial bargain, as most investors are scared away due to how costs can skyrocket if there trying a quick fix. If you get a rockbottom deal because of previous damage, then you might be able to offset the cost that you will have to put into it. It is not the easiest thing to do and not usually the best investment for your money, but with the right deal it could prove affective.

What i would usually suggest is get a older home, that just needs regular rehab work, and see if you can get an over the counter permit for addition if less than 500Sqft. You will usually get more for your money with this, and save yourself unless the headaches.

Im not an architect or contractor, but i would actually take one with you and get real costs before you buy. Or during the due diligence period before you remove contingencies.

What area in San Jose are you interested in that has this old time feel. This makes a difference due to making sure any money spent will get a return on that specific area. There are areas were older homes are that will not give you a decent return due to the overall resell value. Make sure all things align before you take on too much. With that being said its a great time to take on projects in this market, and good luck.
1 vote
Pam Winterba…, Agent, Danville, VA
Mon Oct 22, 2007
This may not be a cost effective process. It is quite costly to move a home and the possibilities of damage to the structure are quite high. My guess is the cost will exceed the value you get. You might want to consider taking the money that you would use and buy a larger home.
0 votes
ian cockburn, Agent, New Orleans, LA
Mon Oct 22, 2007
These changes you are proposing will cost you an exponential amount of money and result in collateral damage for a long time, under and over the basement, from the floors to the roof, to gutters, and much more.

This change is not worth the money nor the headache...start at $120 per sf as a safe bet to get it done.
Web Reference:  http://www.iansellsnola.com
0 votes
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