My parents are talking with a builder in Tennessee about a new place for themselves. He wants to use precast concrete basement wall sections instead of block or site poured concrete. My dad doesn’t have much info on them but he does know conventional footers aren’t used and that the sections bolt together with about 1″ dia bolts. They are simply craned down onto a gravel filled trench. My guess is the bottom of the panel is spread and has an intregal footer cast in. There may be a tongue & groove connection & gasketing between the panels for sealing. The obvious benefit is not having to pour walls during winter, which is when they’re planning on starting. It sounds like there’s a bit of a time savings over poured walls and a bigger one over block. Have you guys heard of these panels or used them? I’ve never seen or heard of them in my area.
Al
Replies
These have been discussed several times here. Try using the advanced search function for "superior walls" or "precast concrete".
You can also check out:
http://www.superiorwalls.com/
Change is certain, progress is not. [E.H. Car]
Thanks, Boss. I'll dig through the archives.
Al
hey Al, I'm getting ready to land the roof on my first precast foundation.They don't have a spread footing just a 10" base that sits on the gravel bed. From what I understand they are about 30% lighter than a standard poured foundation and this lessens the need for footings.
On the plus side they are very straight and smooth with an attractive finish to them. They are also installed quickly by the factory crews. If your planning on finishing your basement the walls are already insulated and have 3/4" pressure treated material for hanging your drywall.
On the downside you have to use 2x10 treated plates with a whole mess of bolts to lock the system to your deck(the deck keeps the panels stable against the pressure of backfilling the foundation)
You must put the deck and pour the slab before it is backfilled and if you have a garage you will have to drill in your own anchor bolts.
The concrete is 5000 psi while a standard poured foundation is only 3000 psi they say that because of this you dont need to worry about damproofing. Like Boss says they have the website but you probably aught to talk to somebody on the crews that install them to learn about any other perculiarities. Good Luck.
Edited 10/31/2002 9:45:06 PM ET by benny
5000 vs. 3000 eliminates the need for damproofing? I think they might be saying that the walls are strong enough to withstand the greater pressure of moisture-laden soil without deflecting, but drainage is still a good idea. Any future plans for using the basement as living space would greatly benefit from a few hours and dollars spent when everything is exposed.Jon Blakemore
Just passing on the info I was given. The county required it any way.
Precasters typically use high strength concrete for several reasons. First, is they can get a higher design strength early, and this allows them to produce more panels per day. Also, the panels get handled and there are usually inserts to lift them, and the higher strength concrete lets them handle them earlier. Higher strength concrete also tends to crack less.
One word of caution - I'm an engineer and I've inspected and done alot of retrofit work on precast structures. (Mostly tilt-up) Problem is they are not very good in earthquake country. Now a basement would supposedly move with the ground in an earthquake, but if this were in any area that has seismic activity, I would suggest cast-in-place walls and conventional concrete footings.
Thanks for the feedback. I didn't know of them being used in my area but one of my customers uses them for retaining walls as well as some commercial work he does. They look pretty interesting-I'd consider them for my next house. This is for my out of state parents-just trying to keep them out of trouble but the builder looks like he's solid so far.
Al