Foundation questions

morkable

morkable

Just Over Broke
Joined
Jan 30, 2008
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As I have discussed before, I am going to build a nice shop next year. I am trying to gather information throughout the winter so that I am prepared for spring and ready to go.

I am planning on building a 40 x 60 shop. And my first question is

* how thick should I make the floor? (probably the heaviest thing that will ever go on it will be a motorhome) (and the floor will be heated)

* am I better off with a 1 or 2 foot foundation wall and a floating floor, or should I go with just a pad.


Also, one other thing, what is the lowest wall you can go with and have a 14' tall door? Do you absolutely need to have 2 feet of header?

Thanks guys
 
A monolithic pour for footings and slab would work, as long as your freeze heave isn't that bad. Also, one thing to consider is if you are putting in slab heat, you need to place that in the creete, which for some contractors will add to the cost of placement, and if doing monolithic it may be harder to achieve. I recommend 6" with wire reinforcement and rebar where the motor home is going to sit. It is honestly not that costly to do rebar the whole way through.
 
We get quite a heavy frost here. I was planning on putting rebar throughout, not sure if would be 12 or 16 inch grids yet. Oh yeah and on edit, I will be running 2 inch insulation under the rebar too.
 
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morkable said:
As I have discussed before, I am going to build a nice shop next year. I am trying to gather information throughout the winter so that I am prepared for spring and ready to go.

I am planning on building a 40 x 60 shop. And my first question is

* how thick should I make the floor? (probably the heaviest thing that will ever go on it will be a motorhome) (and the floor will be heated)

* am I better off with a 1 or 2 foot foundation wall and a floating floor, or should I go with just a pad.


Also, one other thing, what is the lowest wall you can go with and have a 14' tall door? Do you absolutely need to have 2 feet of header?

Thanks guys
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I went with six inch on the floor, go with a higher mph on the floor than footings and wall for hardness, with lots of rebar in all, you should talk with a engineer and builders in your area due to the frost heave etc, I suspect the conventional footing, retaining wall setup, is stongest, my retaining walls and floor are all tied together with rebar, for strength, to prevent movement, and seismic
 
morkable said:
We get quite a heavy frost here. I was planning on putting rebar throughout, not sure if would be 12 or 16 inch grids yet. Oh yeah and on edit, I will be running 2 inch insulation under the rebar too.
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You should check with the government but I think you may need to put in footings in order for the shop to be code compliant.
 
I see both kinds up here.. I think it is due to the high quotient of clay in our l ground. I am going to check on that though....
 
I think you'll see that anything over 750 sq ft needs a full frostwall. I'd put 6 inches with mesh... I wouldn't bother with rebar in the floor honestly other than a few crossbars to tie the footings together.. If you plan on a hoist I'd mark it out before the floor is poured and go a little thicker there for the bolt down points. 4ome doodrs will allow you to get away with 12 inches of header, but then you have. 10x14 ( or whatever size the door is) area on the cieling that you need recessed lighting because there will be no clearance between the door and cieling when its up.
 
dosent the door roll at basically the same height as the opening? give or take 2 or 3 inches? I realize I could be wrong there
 
Most of the low clearance doors I've worked with over ten feet still needed a foot over the header. The smaller 7 and 8 foot doors only needed 6 inches. Mainly to do with the size of the panels the door is constructed with.
 
ahh, gotcha... the reason I ask, is that I am toying with having the ability of putting a fifth wheel or motorhome in there for the winter,, and they are each about 13, 6 high. Other than that I dont really need any higher of ceiling
 
I'd just check with your local overhead door place to confirm what options they have for you before you start putting walls up. I was going to say the extra 2 ft in cieling won't cost that much, then I started thinking.. It is 392 sqare feet of gyprock, 400 square feet of siding, and about 300 board feet of studs and a gallon of paint more on a 40x60 size shack! Damn that's big.
 
Not to mention heat, the higher the ceiling the more heat,, lol.. I have to really sit back and think about the need vs want of putting a 5th wheel/motorhome in there
 
After checking with the local authorities if I go over 14 feet I have to have a engineer design the building... sounds expensive. I really want to build this thing to complete for less than 60k.

I am really leaning towards a slab, with 6 inch floors, 12 inch around the perimeter. 27.5 mpa. What do you think? This floor will be heated and well insulated from the bottom.
 
morkable said:
Not to mention heat, the higher the ceiling the more heat,, lol.. I have to really sit back and think about the need vs want of putting a 5th wheel/motorhome in there
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not if you use radiant heat in the slab. Take a look at the temperature profile in a space using floor heat. Unlike forced air heat, you end up with heat where you need it and not all up at the ceiling.

What I plan to use:
6" for the floor, 4000 psi, 5/8" rebar at 12" spacing (just because I have it).
2" XPS under the floor (up north I'm sure 4" would be even better if you plan to heat all the time, but damn it's expensive), don't forget a moisture barrier too

I am going to use a footing of about 8"x20" with two rows of ICF blocks on top (16" tall each) (may have to adjust based upon your frost line). This provides an excellent thermal break for the slab to prevent heat loss to the outside.

Are you in a location that has required codes (within city limits)? What requires an inspector to come out? Who's to say you put a 14' tall building on a 2' stem wall.

What size pex are you using and what are you using as your heat source?
 
If you are going with steel most of the companies that you buy the kit from provide three sets of engineered drawings in their price, FYI.
 
I am on an acerage, but still have a 14' wall limit. I also have a limit of how big of a shop, based on my acerage. I am allowed something like 4000 sq ft.. but that includes all storage or garage space, including mezzanines. So with the present 3 car garage and a 40 x 60 shop I am about 300 feet short of the limit, just enough to build a mezzanine.

I have quite got that far yet to decide on the size of the pex, I will get my cousin tell me what I need. I will be going with a Lochinvar boiler (I think that is how you spell it) I was planning on 16" on center for the rebar.


As for the metal buildings, I looked at them quite seriously,,, but they are a bit more expensive and just not as nice as a stick built IMO
 
morkable said:
After checking with the local authorities if I go over 14 feet I have to have a engineer design the building... sounds expensive. I really want to build this thing to complete for less than 60k.

Most builders include this in the price, my shop and office had to be done by a engineer due to it being a commercial building and it only added 200.00 to the total price. I think the plans are drawn up by the builder and just need to be approved by a engineer.
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Yeah, my problem is I cant really afford to go with a builder, pretty much going to do most of it myself. One of the few things I am not going to do by myself is the placing and finishing of the floor. Not that I dont know how, just short of manpower
 
do you have a slope to work with? put the building on the slope, entrance on the low side, with enough slope you can even keep positive natural drainage away from the door way without messing with pipe. go in level, come up 1 foot above grade of far back walla with poured re-in-forced concrete and build up from there, less wood wall to deal with, less tall looking structure, but inside you still have your clearance. all excavated material graded around foundation to hide the concrete, and create even better drainage. do a loft setup on side away from motor home for small office, storage..... dog house for when you are on the chit list........
 
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