garage on Grade.....

[financer83rs]

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. Garage is sitting on a monolithic slab that was poured five years ago.

 

[fefarms]

Ideally you should re-grade the surrounding dirt so that it slopes away from the slab at 1 inch drop per foot, for 5 feet. If this is impractical, dig a trench along the uphill side, set in some perforated pipe and drain rock, to carry surface water away from the edge of the building. I would recomment installing a gutter on at least the uphil eave. Use a downspout and a rain drain to direct the roof runoff around the garage and over to the downhill side.

 

[financer83rs]

Thanks for the reply and feedback. How wide/deep should the trench be? Should be abutted right against the slab? Then with the perferated pipe and crushed rock?

Thanks again!

 

[fefarms]

If you don't mind the look of exposed drain rock, you can economize by digging a trench one foot wide and one foot deep, plus enough additional depth at the low end to give you a 1/4 inch per foot slope along the direction of the trench. Put in a couple inches of rock, add your perforated pipe, fill the trench up with rock. If you put this up against the uphill wall, it looks almost like deliberate landscape edging.

 

[Rick H.]

I've got almost exactly the installed condition the fefarms describes and even with no gutters we have had no problems with it. We actually just added more gravel and widened it into a walk path.

Rick

 

[Zeke]

I think people who live in ME or have lived there should answer this. I would be concerned with snow drifts against the siding. Therefore I would probably place a plowable walkway a few inches below slab level on the high sides. With drainage for rain and melt.

 

[nate379]

Unless you raise building 4-5ft there's going to be snow against it. I grew up in Maine and we always pushed the snow against the house and garage to help insulate it. Never became a problem with water getting into the building.

My suggestion would be to regrade. Pitch the slope 8-10ft out from side of garage, even if you had to make a shallow ditch. For here they call for at least 6" drop in first 10ft from building.

 

[Zeke]

That's why ME residents know more than I!