Digging out under an existing home addition

Old 01-19-17, 10:57 AM
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Digging out under an existing home addition

We recently bought a house that has an addition on the back. This appears to have been built using a pre-existing porch, under this porch is not enclosed and has less than 1 foot clearance. This addition has electrical and baseboard heating. We are interested in the possiblilty of incorporating this addition into the house and running plumbing and HVAC in order to add an additional bathroom and bedroom.

As both my wife and I are new to home remodeling and repair, I was hoping someone here could offer us some advie.

What are our options for:
1. enclosing the under the addition
2. digging out under the addition to increase clearance
3. insulating under the addition
Old 01-19-17, 11:15 AM
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Welcome to the forums!

While it can be dug out it might not be cost effective. You must make sure you don't compromise the footer for the room! This is often done by leaving a foot or two of the ground alone next to the foundation and then when you block up or pour the new foundation you'd have a ledge between the new foundation and the old.

Pics would help us better assess what you have - http://www.doityourself.com/forum/el...-pictures.html
Old 01-19-17, 02:50 PM
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Checked with local zoning dept. to see if adding a bedroom would even be allowed?
Septics are rated by # of bedrooms, not bathrooms.
Old 01-20-17, 07:39 AM
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Many questions need to be answered.
What is holding up your pre-existing porch that the addition is built on?
Was that work done with a permit and inspected?
Will excavation weaken that support?
Are you only looking to excavate enough in order to have a proper crawl space or were you hoping for more depth?
Are you planning to enclose under the addition with something structural or just skirting?
Old 01-20-17, 08:24 AM
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It's always hard to suggest bad news but it is better to be prepared for it than to fall into something bigger than you had planned on.
It is possible the porch and subsequent enclosure were not permitted nor inspected. Plus, footing in your climate should be down (I'm guessing) at least 4' below grade. If, and I'm saying if, it wasn't permitted, inspected, or properly build you may be opening a can of worms by trying to improve it. If you are prepared to undertake whatever is necessary, then talk to your local code office for advice.


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