DoubleStud
Structural
- Jul 6, 2022
- 464
We are redoing a drip through deck into concrete topping deck. We are going from 15 psf DL to 65 psf DL. We are redoing everything including lowering the ledger (to accommodate concrete/veneer thickness) and adding blocking between studs at ledger elevation to increase capacity.
The question I have is with the foundation. Currently the piers are 16" diameter sonotube on 2.5'X2.5 spread footing (from the existing structural drawing). I do not have a soil report. In the past the building department has been OK with me assuming 1500-2000 psf soil bearing pressure on small deck projects. I am not sure how to go about it with this project. Would I be able to reuse the foundation? Can I justify a higher bearing capacity since the soil below it has taken under load for years? Do I make them dig it up and extend the footer? Below the deck they also have a stone patio. So digging up the existing piers will mess up the patio floor finish. Assuming 2500 psf to 3000 psf will certainly give me the capacity with the extra DL. What would you do?
The question I have is with the foundation. Currently the piers are 16" diameter sonotube on 2.5'X2.5 spread footing (from the existing structural drawing). I do not have a soil report. In the past the building department has been OK with me assuming 1500-2000 psf soil bearing pressure on small deck projects. I am not sure how to go about it with this project. Would I be able to reuse the foundation? Can I justify a higher bearing capacity since the soil below it has taken under load for years? Do I make them dig it up and extend the footer? Below the deck they also have a stone patio. So digging up the existing piers will mess up the patio floor finish. Assuming 2500 psf to 3000 psf will certainly give me the capacity with the extra DL. What would you do?