Thanks for the Info Bruce, I'm in Eastern Oregon and we accasionaly see a 40
below winter here and I was seriously considering using plastic tubing in my
shop and a solar panel to heat antifreeze and a low volume circ pump.
very high initial cost but should easily pay for itself over time. but
I've never looked into or ever heard of using
wire to heat the floor seems like your power bill would go through the roof
but may be mistaken. I would like to look into it thou do you have any
references or could you email me of the list as I'm shure there are people
that
are tired of hearing about Cement Etc. My shop I'm building is 28x40 so cost
is a big factor. I'd like to get a slab in it before winter. just not shure
what way to go.
-----Original Message-----
From: B&A Kettunen <bekett@uslink.net>
To: Oletrucks Board <oletrucks@autox.team.net>
Date: Sunday, October 01, 2000 10:05 PM
Subject: Re: [oletrucks] garage floor slab
>Here in NE Minnesota, it gets down to 40 below or a little colder in an
>average winter. For an unheated garage, it is almost impossible to prevent
>some hairline cracks.
>
>If you're going to heat the garage, consider floor slab heat, it puts the
>heat just where you need it most and the concrete will last forever. For
>those that don't know, floor slab heat has wires imbedded under the slab
>and heats the slab up to 68 degrees or so. Often this kind of system can
>be put on some kind of interruptable power and, with good building
>insulation, costs a surprisingly small amount to run. You can also do this
>with hot water (use anti freeze) and a furnace, but this gets a little
>expensive to install, even with plastic pipe.
>
>The main problem with freezing is frost heaves. These are caused by water
>(surface or ground) under the slab welling up to the frost line and
>freezing (expanding). They tend to lift up, and cause any cracks on the
>surface to open up. A little water dripping off a truck and then freezing,
>and pretty soon those hairline cracks are major faults. The only way to
>avoid a frost heave on a cold slab is to have excellent drainage all the
>way down to below the frost line. That's around 8 feet here. This means
>digging a hole, putting in drain tiles, and backfilling it with gravel that
>drains well.
>
>Putting rebar near the bottom of the slab is good for keeping the top tight
>if the soil under the garage settles and the slab sags. To keep it
>together on top with the ground heaving from underneath, the bar should be
>near the top of the slab. The only problem with this is that any water
>perking down into any hairline cracks, especially with salt, causes the
>rebar to rust and pops the concrete. To fight this, use galvenized rebar
>or epoxy coated rebar.
>
>When you pour the concrete, keep it wet (not just damp once in a while) for
>at least a week or you will get lots of hairline cracks as it shrinks
>before it sets fully. Small cracks only get bigger.
>
>Hope this helps. Maybe some of the Canadian members have even more ideas.
>With all the members on this list, I'm sure I'm not the only engineer.
>
>Bruce Kettunen
>57 3200
>Mt. Iron, MN
>
>If you want to separate the floor from the grade walls around the edge,
>that's fine.
>
>>How thick is your slab and do you get cold temps? Would really cold temps
>>increase the likelyness of a crack happening? What state do you live in? I
>>thought about the fiber stuff. I'll look into that tomorrow. I want the
whole
>>slab as one and not sectioned. thx jim
>>
>>"R. Welch" wrote:
>>
>>> I used 3500# concrete for a floor in my barn and did not use rebar.
>>> Instead, the concrete mix had fiberglass mixed in with it - I think it
cost
>>> about $5/yard more, but they said the slab shouldn't crack. Its been 2
>
>
>oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
>
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
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