I’m building a new outside wall at ground level which which will have double doors and therefore has to stay at ground level. I want to protect the sill board so any moisture touching that wall will not rot the sill board. I was thinking perhaps wrapping the sill board in plastic or painting the sill board with fiberglass paint. Other than using pressure treated lumber, does anyone have any other suggestions for moisture protection?
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Replies
It's tough to do anything effective over the long term. Even if you protected the wood with a pretty well sealed barrier, moisture will still find it's way in, and will have difficulty coming out, so you may make matters worse.
Constructing a wall that close to ground presents other problems as well. It will subject the siding and bottom edges of the sheathing to splashing water and piling snow, rot from leaves and debris sitting against the wall, attraction to insects, and looking funny. In some places code requires at least of 8" of height between the ground surface and the bottom of the siding.
Instead, how about the foundation coming about 12" above grade and building the walls on top? Where the door is, drop the foundation wall about 6", so it's 6" above grade, and construct a ramped concrete walkway. So, your finished floor inside will be about 6" below the top of the foundation. The foundation inside will be covered with finished wall and baseboard.
I thought of that as well. This 'room' used to be my 2 car garage which I have rescued as my work shop (there is even a tree now planted in front so it can't be reclaimed). My intention was to remove the 16' garage door and replace with a wall with double doors (to make it easier to get things in/out) and a couple of 3'X3' windows. Having the sill at ground level was tempting to make it easier moving things in/out, but I agree with your thinking about eventual problems. Thanks for the confirmation of my concerns.
Raise the foundation 4-8 inches, except at the door level, using concrete block. (You should probably drill holes and pin the block to the slab.)
is your sill board what we call a "kick board " under the door sill ?
close to the ground like that we would use a piece of Trex.. either leave it natural or paint it..
it won't rot and will take a lot of abuse
Mike Smith Rhode Island : Design / Build / Repair / Restore
But why not just use an aluminum threshold and put it right on the slab?
don't know... what's the finish floor ht.?
does the PT sill run thru ?
i'd hate to see what an aluminum wrapped kick board would like like in 6 months
that's one reason i asked if it was the same as what we call the "kick board".. wanna know why we call it a "kick board " ?Mike Smith Rhode Island : Design / Build / Repair / Restore
What are you sheathinfg the wall with? What kind of drainage conditions....did water come into the garage before?
If the drainage is ok, a pressure trated sill, with good flashing details on the exterior sheathing, will last longer than you need it to....