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Home Improvement--General/How to create an "awning" over open cement blocks under a deck?


QUESTION: The foundation of my house has a shelf once intended for a stone front which was never installed. It's 3 cement blocks below the bottom of the siding. It's not readily accessible since a low 2-level deck was built over it and I think the open cement blocks in the shelf (which should have been capped when it was built) might be letting water into the basement. One level of the deck is about 2' high and the other is about 18" high. Chipmunks live in some of the block openings and I won't cement over them. I've been unsuccessful evicting the ones in the most visible hole, since they keep moving the stone I placed over it as a test.

I'm trying to figure out what to use and how to use it to create a slanted "roof" from above the open blocks (possibly wedged behind the siding above them) to the deck supports, the angle being approx. 26" under the higher deck level and 23" to the lower one. There also are two inside corners and one outside corner at the house entrance to contend with. I've removed some boards from the lower level with a car jack (the boards were nailed in) and have only 12" from the front of the house to the first 12" x 3" redwood beam (resting on the narrower side) to get to the shelf at the 20" long lower level.

Due to the lack of working space from the deck support beams and minimal height, I think I'll need to do prefab work of some kind, but I can't figure out what to use. (The guys in the pro department at 2 different Lowe's wished me luck.) I also need something that can resist the elements and isn't too difficult to cut so I can trim it in place, if necessary.

ANSWER: Without fully understanding all the conditions you describe my guess is that you will use aluminum flashing bent to the profile you need.

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QUESTION: I think you understand what I'm getting at.  One problem with flashing is that it's difficult to cut and I'd probably have to do some of that laying on my stomach in a confined space.  I'm wondering about attaching a strip of flashing to the top of a rigid board before installation.  The flashing could slip behind the bottom edge of the siding (not much--it would be tight and I'd have to caulk it) and the rigid board could be wedged in place between that and the base of the support beam for the deck.  Any thoughts on what might work for the rigid board part?  I'm guessing some kind of roofing or siding material, but haven't come up with anything yet.

Aluminum flashing will not be any more difficult to cut than asphalt shingles. You will best have the correct pair of snipe - probably something with offset handle. Prebend the profiles, crawl under the deck and install them. They can be overlapped so cutting will only occur at an obstruction.

How you attach the pieces to the house will be the challenge. They need to be mechanically secured so they do not fall off. You can consider installing a nailer onto the CMU then nailing the flashing to it.

All in all I think some research into encouraging the chipmunks to move on and installing brick along the ledge is the best approach.

Home Improvement--General

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Thomas Buford


Licensed Architect in Virginia since 1984.
New Homes, Additions, Alterations, Outbuildings, Failure Forensics;
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