I’m planning to build a garage (26’x26′), doing some work myself (framing, siding etc.) and hiring out the rest. Question about the foundation – I’ve talked to several concrete guys and a couple of builders and all but one of them said that a block foundation would be easier and cheaper than a monolithic pour. The place where the garage is going is a gravel parking area right now, roughly level. Because of the slope of the ground, at the left side of the area, there’s a 2′ high retaining wall that will be coming out. That’s about where the left wall of the garage will be. The guy who suggested the mono pour is also the cheapest estimate. I don’t understand. Everyone else is telling me that block is cheaper/better for this kind of thing.
Are there any foundation experts out there who can help explain this? BTW, I’m in NC so the footings only need to be about 12″ down instead of 4′ like up where it snows sometimes <G>.
Thanks!
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The idea of a monolithic pour is that footings and slab are one unit. Even in the north you can do it without going deep if you have good drainage soils compacted under it because the water in the soil freezing is what damages the slab. If you lead the water out, no freeze and no damage.
In your area, Block is very commonly used and wages are a little lower. Since block is common, there are plenty of masons ready to go. It may be that 'for them' it is cheaper to lay block. What you are intrested in is 'for you'.
Since this ground is already a gravel parking lot, it appears that it already has well tamped, bearing, draining soils so little site prep would be needed. That sounds ideal for monolithic!
The clinker in the mix is that one corner being low. Gravel would need to be hauled in and tamped to bring it up level. Maybe this one guy is much cheaper because he's one of those fly by contractors with a box full of shoehorn shortcuts and tailgate warrantees. Or maybe the other guys can see something in the lot and soils that I can't from here that requires moire prep than you describe.
Maybe a little visiting time to ask questions of them all without trying to sound like you are challenging their judgement will elucidate some good local knowledge. KeithC is from down your way and will have more knowledge of local practices.