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I have a 16×16 wood shop that I would like to add a 9×6 addition. The 9 foot length will be attached to the building. The framing will be no problem but I am not sure how to deal with the foundation. The wood shop has a monolithic slab and there is a drop off in the grade behind the shop. The drop off is about one foot down for every four foot out. The building is in Florida and sits on pure course sand. How should I set up the foundation for the new addition. Where can I find information that will tell me how to do it right.
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Replies
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Hi Paul,
Monolithic slab normally refers to pouring the slab and perimeter ftgs/walls at the same time.
Is there a thickening of the slab at the outside perimeter or some type of foundation wall?
Regardless, you can add a small addition like you described by simply insuring that the sand you add to bring it to grade is well compacted before you install the new slab. This will go a long way to ensure that you don't have any settling later on.
Then you frame the addition as was originally done with your main shop.
Gabe
*See blue's post on "How much sand for 1000' of block" It may not help, but you'll feel a whole lot better about your own situation.
*Paul, when you go for your building permit you can pick up a copy of the way your permitting officials want it done, or take a look at the enclosed diagram.The depth of the footer should be a minimum of 12" below grade (original undisturbed ground). Currently in Duval County, FL, this diagram would be wrong if it was something you brought in. This just happens to come from a set of STAMPED plans. Change the anchor bolts to 5/8" dia. X 10" with 3" washer @18" O.C.Now you just have to have a little compacted fill so you don't spend all your cash on concrete. Or you could disregard and pour a separate footer (12"D X 20"W) with a 3 course stem wall, backfill and pour.
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I have a 16x16 wood shop that I would like to add a 9x6 addition. The 9 foot length will be attached to the building. The framing will be no problem but I am not sure how to deal with the foundation. The wood shop has a monolithic slab and there is a drop off in the grade behind the shop. The drop off is about one foot down for every four foot out. The building is in Florida and sits on pure course sand. How should I set up the foundation for the new addition. Where can I find information that will tell me how to do it right.