trying again, looks like the first one got lost.
anyone ever tried those precast foundations w/ a bell at the bottom / integral footer? As I understand, they rest on gravel & are bolted & caulked together.
If these pass code, what would be wrong w/ pouring conventional footings on a bed of gravel. It seems to me that leveling & general working conditions would be much easier & more pleasant.
Replies
That would be good, the only difference is if you don't need it then it's additional cost. And you know that footers are really just big long rocks under your building. And buildings are really big boats that float on really big rocks.
Clay
i have never used precast foundation sections, but have much foundation experience!, pour in place, or retrofit. as clay said the gravel is an extra step you don't need with pour in place, and as one step in a designed system of installing pre fab sections it probably serves to function more than just for ease of installation.
i dont understand how it could be easier to level or work on and around a footing if the footing itself is poured on gravel.
leveling gravel or earth still involves a shovel, manual or automatic, and while the gravel may be easier to move with the manual shovel i would sure like to have the automatic (backhoe) shovel there to place it into the fooyting trench.
and the gravel will help working conditions only if it is muddy and you spread enough gravel to walk on, it doesn't help to work in the footing unless dobies holding reinforcing steel are sinking in the mud. i would just use spots of gravel for the dobies.
please let me know if i am missing something, you may have a good idea but i don't understand what you mean. on really big jobs we pour a rat slab first (after piles or caisson's are in), then build the structural concrete foundation on that unreinforced rat slab. this rat slab greatly improves working conditions in a big muddy hole, and usually the first thing installed on the rat slab is a waterproofing membrane. i would love it if all home crawl spaces were required to have one, finished nice and smooth so you could get around on a mechanic's creeper or a skateboard when you have to work under a house!
current employer dug his own hole w/ trackhoe. 28' x 52' over 2' out of level from one side to other. He told us to go ahead & set footing forms, to just build down in the low areas. Melt is happening now, all mud where it is not ice or high.
His finish work is exceptional, but he seems not to realize that the $$ spent now can lower the overall cost later.