Replies

1. 
   Guest_ | Sep 29, 1999 09:03am | #1

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   Search the archives. This topic was discussed the week of July 26th. Use "Superior Walls" as your search string. Also, there was an article (7/97) in JLC about this product although it tends to be more informational and less of a commentary.

   The thing that first struck me as odd about these precast walls was that the bottom edge of the wall serves as the footing, and is only about 8" or so wide. After further thought, I realized that the gravel has a significantly higher PSF rating than soil and that is why the "footer" can be much narrower.

   The seams in the walls are sealed with polyurethane sealant. Seems like a possible leap of faith to "bet the house" on caulk??

   On the plus side, these basements can be built in a day. The 5000PSI concrete is stronger and less permeable than traditional poured basements, and the integral rigid foam insulation gives a built in R5 value with "stud bays" ready for batt or blown insulation and finished wall covering.

   I bet the rigid foam acts as a "wet side" vapor retarder too, although I do not know this for a fact.

   The distributor/manufacturer in my area recently started offering the system in crawl space foundations although I do not know how cost competitive they are.

   Also, check with your local building officials to be sure that they will approve the use of this foundation system.

2. 
   Brad_Jones | Oct 02, 1999 10:40pm | #2

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   >I have heard stories of great success and of terrible failures with precast walls.
   >I assume the lack of footing has been evaluated by civil engineers. Maybe our insistence on 24" wide footings is overkill, a rule of thumb applied even when unnecessary. People make assertions that we need big footings, but who has seen data (not anecdotes, but substantive data)?
   >A well known franchise in our area of NY built a basement for a friend. Fast installation, same cost as poured, but ready to finish with sheetrock without extra preparation. The high PSI concrete is excellent at keeping out moisture, and the basement is bone dry, even in humid July.
   >I met someone who had the same franchise install the foundation. Before framers started, it cracked. A civil engineer tested the concrete, and it was less than 1000 psi. Now they are tied up in a lawsuit.
   >A builder I had bid on my house had prior experience with this franchise. One time, they installed the first 3 sides lined up nicely, but side 4 was 3/4" higher than side 1 at the corner. Other installations were out of level by +_1/2". He asked the mfgr. why, and they said some set crews are better than others.
   >We didn't hire that builder, but will get a poured wall. I won't be a learning experience for a new set crew. Our GCs favorite mason wanted $24,000 for a 9ft high wall, or $17,000 for 8ft. I found another mason for $18,000 for the 9ft. He guarantees level within 1/8".

3. 
   Amy_B. | Oct 02, 1999 10:40pm | #3

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   Is anyone familiar with precast foundation walls with a gravel footing. Superior Walls is the only manufacturer I have seen with this system. Any opinions would be appreciated.