I am putting in a small front porch/deck 8'x8'. The front is terraced, dropping down in 4' steps to the next level. I am trying to keep this simple, but get as close to the terrace edge as practical.

3494

The two questions are
(1) given well-designed retaining walls supported with geotextile fabric, would it be safe to put a pier just in from the frost linein both dimensions, i.e. 42" deep AND 42" from the wall.

(2) in heavy clay, what load could be expected on the soil? I figure a maximum load on each pier of about 950 lb. (19 sf x 50 lb/sf). Will 8" pier with 12" footer suffice?

I realize this is not a simple issue. We live in the country without access to a building inspector, so are winging it.

Thanks!

I would always recommend over-engineering any project (within reason, of course) but when it comes to the basic structural components (ie. Footings, headers, etc.)... If you don't "over-do it"... not enough can be catastrophic. You shouls be able to get information from your local county offices to determine the average soil bearing pressure for your area. Clay typically has a maximum load bearing pressure of 2000 lbs. per square foot.

Here is a source for you... Good luck and most important... have fun!!

http://www.nyashi.com/newsletter/2006/April%20files/footings.pdf

Thanks for the input

Good article too