Hoping someone can help. I'm building a 24X26 detached garage and was
wondering what the dimensions the concrete pad should be. The garage
will be purchased as a package from a local building supply store. Do
I pour is exactly 24x26 or would I need to subtract for the vinyl
Balzac, AB, Canada
Check with the store.
There must be drawings of the assembled building that will give the
The completed garage may not be exactly the advertised dimensions.
I would guess that the dimensions will be for the framing.
Sheathing and siding will be in addition to that and do not need a
Don't forget to thicken the slab below bearing partitions and columns.
On 13 May 2006 08:02:38 -0700, " firstname.lastname@example.org"
My friend built a longer than 2-car garage with a kit from 84 Lumber,
and I think he arranged to copy the instructions before he took
delivery of the kit. Not sure, but I could ask.
His garage came out very well, with a propane furnace and AC, and room
in front of the cars for bulky tools and parts etc.
He had one friend who knew some carpentry and had a power nailer,
along with a group of friends, build the garage in 2 days (minus the
single overhead door). Then he did details later.
As to foundations, he had that professionally done, with a trench in
the middle and black plastic grills covering the trench, and the floor
sloped down to the trench. This way he can wash cars inside the
garage. This was important to him, I guess, or maybe he added it after
he realized he was hiring a pro for the slab anyhow.
As to garage doors, my own opiniion is that one for two cars is a lot
better than 2 one-car doors. This way if you have a lot of junk you
can park in the middle, and even if you park at the side, it cuts in
half your chances of hitting the garage with your car. There must be
loads of people who hit that thing in the middle.
There's also the issue that if you have a fairly large car, the
standard 8 ft door is *very* narrow... I have a new Dodge pickup and I
would probably need to fold the mirros in if I wanted to put it in my
garage... If I was putting in a garage with single doors, I would go
with 10 ft doors instead with more than just a column between the two
doors... A minimum of 2 ft between the doors, possibly 4 ft... I
prefer if it is possible to open the doors to the cars inside of the
garage and they not hit the car parked in the other spot...
Basically, spend a couple extra dollars now and do it right...
On 13 May 2006 08:02:38 -0700, " email@example.com"
He'll want to ensure that the footers go below the frost line... Here
in Houston, we don't have to worry about frost, but I see 30" footers
around the perimeter of the detached garages on the new houses that
are currently being built...
When you pour the footers for the pad make sure that you stub up a piece
of rebar at the location were your electrical supply will enter the
building. The piece that you stub up should be galvanized or stainless
steel the latter being better but much harder to obtain. As long as the
piece you stub up is well tied to the rest of the footer steel it will
be a really good grounding electrode for the buildings electrical system
providing that you do not use plastic sheeting or any other non
conductive material to line the footer trenches. If you do not include
this simple step in the footer prep you will be stuck with a markedly
inferior grounding system.
"This alternating current stuff is just a fad. It is much too dangerous
In Alberta, you have frost, in most areas, severe frost. Your foundation
will need to have the perimeter deeper than your local frost line. Your
local town or building committee will tell you how deep this needs to be,
also check out needs for a permit.
Failure to address the frost problem may result in the entire slab
foundation progressively failing after each winter is over.
Ideally you build garage with a raised concrete edge / curb around the
permiter, so the wood sills are well away from ground and water
install a empty pvc conduit or pipe to make getting power indoors easy.
way easier than drilling later
Uh, no. The idea is that the sill plate should be one or two courses of
block above the slab, inside and out, so water never can pond up against
it. It won't rain inside the garage, but you should still slope the floor so
whatever does get in or drips off car will flow back out the big door.
Around here, garages usually have foundations just like a house, down below
frostline, and include an inside ledge to catch the inside slab, which is
usually poured almost last, once the structure is roofed in. Makes it a lot
easier to get the slopes right, to rough in any utilities, etc. If I was
going to drop a kit garage on a prefinished slab, I'd include monolithic
footers in the pour, and either form up a 12" curb to catch the wall, or
have rebar sticking up to drop block over and mud into place. Lumberyard
should have a stack of the foundation layout drawings to go with each kit
they sell. When framing, make sure the garage door opening and/or door you
order match the header to slab distance. Same with the service door. IMHO,
an extra course of block does wonderful things for interior headroom, and is
real cheap to add when building the thing.
No, hopefully it will be built well enough to keep the rain 'out' <G>.
You need the raised (6" min above the outside final (soil) grade)
foundation to keep the siding out of the dirt etc.
You pour the stemwall/foundation( which sits on the footings you poured
below the local frost line..Alberta, I'm guessing min 36" deep) first.
Leave the area of the foundation where the overhead door(s) are going to be
4" short so that once the 4" floor is poured, you are at the proper grade.
Also, allow an 'extra' 1.5" on each side of the door(s) foundation cut so
you can run the framing 2X6's down to floor level at the side of each door.
After those forms are stripped at a later date, you snap a chalk line along
the inner perimeter where the floor is going, allowing 1/8" per foot slope,
back to front (down) toward the door(s). This slope takes care of any sno
melting or water that gets into the garage. I'd put down at least 4" of
compacted 3/4 minus gravel where the floor is going to go, Then you pour
the floor to the line and "out" thru the spaces left for the door(s)
So to sum up, inside the garage, I'd have about 4" of foundation wall above
the floor (chalk) line [at the back-more at the front because of the slope],
4" of concrete floor below the line and 4"' of gravel below the concrete
for a total of 12" total 'dug out' depth relative to the top of the
foundation. I'd put rebar in the floor too 24" on center. Some use wire
mesh, some use a chopped fiberglass additive in the concrete instead of
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