Garage Pad and concrete block

I'm building a 24 x 28 garage/shop and would like to have more than an 8 foot ceiling height in it. It's going to be a 4" monolithic pad and I was thinking of laying 1 or 2 courses of 8" concrete block and building with standard studs to keep from doing lots of cutting. One corner of the pad will be about 16" - 20" below grade, but I won't be backfilling around it, so I think I will be ok.
Some questions... 1. Any issues with this approach for increased height? Will put j bolts in block and pressure treated sil plate.
2. When running the electrical conduit (stand alone garage), would you run the underground conduit through the floor/block so it goes straight up the inside walls?
3. If I am using 1 or 2 courses of block, is there a recommended way of tilting up the stick framed walls onto the block/sill plate?
4. any general suggestion/things to look out for?
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What does your zoning requirements say? Where I live you will not be building walls on a 4 inch pad even with steel in it. Wall require a foundation, where I live that would be a stem and footer. Stems are a mininium of 24 inches wide and 12 inches deep. Footers are usually 8 inches thick and height as needed.

Sure would depend on the lay out of the building for me. I have done it both ways. Conduit is more expensive but changeable. Last garage I did was with 3000 Wiremold. Got the Wiremold for a song and then I could just put what I wanted where I wanted.

See number 1

Call the zoning folks and have a visit with them before you walk off that short pier. Could save ya a peck of trouble.
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Sorry, let me clarify, monolithic pad that is 4" in middle and has 12" on the edges.
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Maricopa county, Arizona would not issue a permit for your "structure". Nor would any other building department that I am familiar with. Here if the structure is more than 150 sq ft of roof and or more than 6 feet tall it needs to be engineered.
You need to talk to the code enforcement guys in your area. Unless you really like those swims after the walk down the pier.
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I second that. In S Fla where frost heaving is not an issue we still need a 8" deep x 12" wide "bell" around the perimeter of a slab we are building on. It needs 2 #5 rebar in it. If you are anywhere that the ground freezes this footer must be below the frost line.
If uplift is not an issue you can just imbed J bolts in the top course of the block wall to anchor the stick built wall. If this is a wind code area you need rebar tied to the footer steel, extending up to the top 2 courses of the block that are poured solid with #5 rebar across the top of that in "U" block. The wall gets bolted to that with straps into the studs and straps from the top of the studs, over the trusses.
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On 12 Jul 2005 11:07:12 -0700, snipped-for-privacy@mail.com wrote:

The main issue I have is why. If you're intent on a CMU stem wall, why not just pour a standard footing and build up from there? If you're intent on the monopour then use longer studs. You don't say -how much- higher than 8' you want. If it's say 10', buy 12 footers and whack them off. You'll need the offcuts for blocking anyway.

No. My house is CMU/slab on grade and I hate having wiring and plumbing buried in concrete. I'm doing a bath remodel and have to change some plumbing in an exterior wall. What a PITA.

Depends on how much muscle you have. I built my garage mostly by myself. 2 X 6 X 12' DF studs with the stem about 6" above the slab. I'm a ham radio operator and had some sections of steel radio tower around that I used as gin poles for some lifting when working alone. (I used the same technique to lift the 30' I-joists and the 8 X 12 X 16' garage door headers) Otherwise my neighbor and I were able to tip up 12' wall sections but it's tricky. A couple of more hands would make it -much- easier. Nail on the braces with one nail before lifting so that you only have to nail off the bottom end when the wall is plumb.

Make the slab 2" thicker and use some rebar.
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wrote:

I did up to 16' sections on a full foundation over 1' above grade, with ~ 12" of exposed trusses above the sill plate, so approximately 2-2.25' above grade. Only 2 of us worked on it, my wife and I. We did the 50'plus section in one piece and used my truck mounted winch to lift it, including microlam headers for the bay window.
Mike D.

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I built my garage over the winter, and did 9' walls with 104 5/8" precut studs. No cutting required.
We tend to run conduit up to outside wall of the garage through an "LB" into the building. This will vary from area to area. I am in Wisconsin.
JK
snipped-for-privacy@mail.com wrote:

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"Thickened Edge Monolithic Slabs" are common here in the Pacific Northwest, but see your "Garage Height" thread to see my reasons why I decided against that type of foundation.
I recommend a standard footing, with perimeter foundation wall. Then pour your non-structural slab.

I chose to run my conduit up through the footing and perimeter foundation wall (before we poured the concrete). This keeps it out of sight, and provides a little extra protection.
The alternative is to run the conduit on the exterior of the building, then punch a hole through the wall to connect to your electrical panel. Seems messy and more vulnerable to me.
I installed two 2" conduits for electrical, two 3/4" conduits for phone or other use, and a couple of 1" PVC pipes before I poured the footing/wall. I only used one of each, but it was easier to install the extras now in case I need them in the future.

My wife and I worked alone, and built our walls in 8' sections. I cut all the PT sills to length first, drilled the holes for the anchor bolts, and made sure they all fit before proceding. Then, I framed up the wall section on the garage slab, and nailed on the plywood siding. I placed a foam "sill sealer" on top of the foundation, then my wife and I got on each side of the wall, and lifted the bottom edge up onto the foundation. We then moved down to the top end of the wall, and tilted it up into place. She held the wall plumb while I banged it into position, loosely tightened the nuts on the anchor bolts, and nailed it in place. Any "stubborn" walls that didn't line up right were easily coaxed into place using pipe clamps to pull the wall sections together. It's a bit more difficult than just tilting up on a flat floor, but not much.
Anthony
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good to know and thanks for the info...how did you connect the 8' sections together? by nailing the studs on the edge together? does this cause any structural strength loss at all?
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Each section consisted of a 2x6 pressure treated sole plate, a 2x6 top plate, and seven 2x6 studs (16" OC). This framework was then covered with two sheets of 1/2" rough sawn plywood (like T-111 without the grooves), nailed every 6" around the edges and every 12" in the middle. The studs were cut at 90.5" so the plywood could overlap the foundation an inch, and accomodate a double top plate. (It helps to use a scrap 2x6 as a gauge for the second top plate when nailing on the plywood. This leaves 1-1/2" sticking above the wall to overlap the second top plate when it is installed.)
We would build the section, tilt it up onto the foundation, use small sledge hammers, crowbars, clamps, etc. to get it aligned and pull it tight against the previous panel. We then tightened the anchor bolts to pull the section down level with the previous section, and nailed the two panels together.
Sometimes the panels go up easy, sometimes it takes a bit of "persuasion" to make them fit tightly. :) On a couple of occasions, this meant loosening the anchor bolt on the previous panel, and prying it up slightly to align the two panels. Then they were nailed together, and the anchor bolts retightened. Thankfully, most panels went up without any problems.
Once the panels are in place, a second top plate overlaps the gaps between panels, effectively tying them all together. I then nailed the top of the siding to the second top plate all along the top of the wall. When all walls were finished, I went around and snugged up the anchor bolts (not so much as to compress and damage the wood though).

If anything, it should make it stronger. In effect, you are making a post (doubled 2x6) every 8 feet where the panels join. And, every sheet of plywood bears on a full stud on one side, which offers more support than two sheets landing over a single stud. And, once the second top plate goes on, it's all tied together into a single wall anyway.
The only real negative is that you end up using an extra stud every 8'. But in a 24'x28' garage, that's only about 10-15 extra studs. Small cost in the overall project.
Also, I used plywood with a "shiplap" edge. This meant paying attention to which edge went over and which went under as I assembled the panels. I made sure each new panel would overlap the previous panel. This sealed the gap between sections, and was easier to align than trying to force the new section under the overlap of the previous panel.
Because of the long headers in the front wall, I built the front wall in place. I assembled the small wall sections on the floor, then bolted them to the foundation. The door headers were then installed, and everything was plumbed and braced. THEN I nailed the plywood siding on, and cut out the door openings. Because of the size and weight of the headers, it would have been difficult to try building these as panels and lifting them into place. By temporarily screwing 2x6 blocks to the top edge of the plywood (where the second top plate would go), I could basically "hang" the sheet on the wall and have it support itself while I nailed it in place.
Once the front wall was done, I built two short 4' panels for each of the side walls. This helped brace the front wall, and made up the difference in the 28' side walls (28' doesn't divide evenly by 8'). Then the rest of the garage was built with 8' panels.
Take your time, work slowly, and plan through what you're gonna do before you do each step. The only time I really had problems is when I would get in a rush. Also, mistakes happen, expect it. Think it through, take things apart if needed, and do it right. It'll seem difficult at first, but you'll be a pro by the time you finish the building... :)
Anthony
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Check your local building code. What you're suggesting doesn't sound right. If you put up a structure that's not to code and something goes wrong you open up a number of risks, least of which would be your insurance refusing to cover the loss.
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On my detached building I just went on the outside of the building with my electrical service panel/conduit etc..

Consider doing the whole building in block. One trade, two half days for two lifts on a building that size... Price per square foot is competive to stick frame when you consider all the trades/material that goes into it. My neighbor and I both built the same size detached shops within 6 months of each other. Mine was block, his woodframe stucco... both ended up at the same price per square, but mine was dryed in one third the time....
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