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Brian LaCroix
06-06-2011, 08:30 AM
I have a garage that is 26' X 28' that is at or near grade. Along two walls it is 3" above grade, and along the other two it is essentially at grade. The garage has pressure treated sills and is sheathed with T1-11 then vinyl sided over that. Any suggestions as to preventive measures I should take? I live in Maine. Any help would be appreciated. The pics are prior to vinyl siding.

MARVIN TOWNSEN
06-06-2011, 08:38 AM
I assume it is a monolithic slab, and if so does it have footings under the slab?

Brian LaCroix
06-06-2011, 10:00 AM
Sorry i should have included that. It is a four inch slab with 8-10" at the sides on top of foam.

MARVIN TOWNSEN
06-06-2011, 10:21 AM
Sorry i should have included that. It is a four inch slab with 8-10" at the sides on top of foam.
8-10" of concrete? Does it have a footing under the slab?

Brian LaCroix
06-06-2011, 10:36 AM
Yes it has a footing that is 10" thick by 16" wide then slopes up to 4" towards the middle. The foundation was poured 5 years ago. The whole slab is sitting blue foam board.

MARVIN TOWNSEN
06-06-2011, 10:55 AM
The reason i asked about the footing was erosion reasons. I would at a minimum

1. gutters and proper downspouts with a minimum of splash blocks

2. remove all soil to at least 4" below the siding.

3. make sure you have proper drainage (gutters are a part of the drainage system) around the perimeter.

I would also be concerned about the uphill runoff from snow melt and heavy rains, so i would install a drainage system to prevent flooding ( at least a redneck version i.e. a ditch)

There are other things you may do to prevent rot which i am sure others will sound off on

Garry Sorrells
06-07-2011, 05:53 AM
Unless you are in the no snow zone in Maine you should add an elastic flashing membrane around the bottom of the sheathing ( 4 ft) . There are several out there in the market.

John Kogel
06-07-2011, 12:27 PM
One mistake I often see with the gutter installation is the location of the downspout. On the high side, where your truck is parked, make sure the downspout drain on the gutter is at the rear, so you can direct the water away around the back of the garage.

Don't skimp on the house wrap, building paper or whatever. Use lots and seal it well at the windows and doors.
When you install the vinyl, face your laps towards the back and they will be nearly invisible. Read the instructions. OK, you've already done that. Enjoy the cozy, dry space. :D

TR Platt
06-08-2011, 05:17 PM
The sills should be 8" above the soil, minimum.

Grade should drop 6" in the first 10' away from the walls.

I would create a swale on the high side and direct the water around the rear.

As suggested, gutters will also be a tremendous help.