Concrete soon to pour. Need advise

[mybuickgs]

Soon to start pouring the footings and stem walls for the 60'X30' garage project. For every question I get answered here I come up with two new ones. This site is great.

1. Since I am putting radiant heat in the floor... is my assumption correct that the insulation between the stem wall and Floor will also serve as a perimeter expansion joint?

2. What about the perimeter slab area where the overhead doors close? Do you insulate vertically along the slab in this location as well (between slab and drive way approach)? If so, Do you seal this joint?

3. I have read dozens of threads concerning expansion joints or saw cuts in the slab itself and still confused. I plan on finishing the floor with epoxies and can't seem to find a consensus what is best. Any advise?

 

[AlphaGarage]

1. Yes
2. Don 't know (Typical SoCal ignorance, "Insulation? Who needs insulation?")
3. Go with the recommendations of your concrete contractor. Saw cuts are much easier to fill later on if you're going to want an overall smooth finish, but some contractors like to form them right after the pour.

Spec a light broom finish with no sealers and you'll be ideally set-up for an epoxy coating (ideally using Wolverine coatings ) 28 days after the pour.

 

[mybuickgs]

The company that has quoted the supplies for the radiant heat sent me this as an option for the garage door area. Any thoughts?

 

[jmh21586]

Couldn't there just be a saw cut there instead of the insulation and plastic??

 

[galwaytt]

Couldn't there just be a saw cut there instead of the insulation and plastic??

No, otherwise he'll be heating the Great Outdoors, as well as his floor !

...you could use a tile to cover the 'joint' as well, but if you can find something insulative (non thermally conductive), it'd be even better.

I have to say, though, that 2" of insulation isn't a lot for UFH. Here the regs have changed now, and iirc it's a minimum of 4" of insulation under UFH. We make product using DOW's Styrofoam - LB-X it's called, which is a structural foam, with a 10(Y)300 modulus. Used quite extensively under even very thick slabs (say 18" thick........)

Example, I have 4" in the house over slab on Ground Floor, and 1" over the ply deck on first floor. Then I have 70mm sand/cement screed over that, upstairs, with the UFH in that screed.

 

[GeorgiaHybrid]

The company that has quoted the supplies for the radiant heat sent me this as an option for the garage door area. Any thoughts?

If you use this detail, make sure that you have some sort of attachment to the slab on the cover plate. You can use something like a bent bar anchor (1/8x1 1/2) with a 3" or so leg that is welded to the plate at a 45 degree angle that has a 1" or so return at the end to "hook" into the concrete. Place them at 24" C/C and it will keep everything in place.

If you are going to have this fabricated by a steel shop (instead of DIY), have them weld 3/8" or 1/2" HNS (Headed Nelson Studs) at 24" C/C as an alternate to the bar anchors. As for the plate, if you want smooth edges, buy bar stock or UM (Universal Mill) plate. Unless you ask for it, most supply houses or fabricators will shear or cut this from a larger plate. A shear will leave a "pinched" edge and the flame cut will need to be ground smooth for appearance.

Make sure you galvanize the plate (or use a three coat epoxy) before installing it. It will last a LOT longer that way. Bare steel like this can rust out in a few years unless protected if exposed to a salt/water combination.

 

[mybuickgs]

Great ideas thus far. I am wondering how many of you out here with radiant heat didn't put any insulation in the overhead door area? and has it caused a problem.

Or better yet, if you did how did you install?

 

[D.J.]

GeorgiaHybrid: Could you enclose a attachment or drawing of what you are speaking of?
I don't guess I understand what you are talking about. Pictures would be great!
Thanks D.J.
________
Montana Marijuana Dispensary

 

[Engine-Ear]

Hi mybuickgs-

See attached for how I did it. I have three separate circuits that are 'zoned'. That allows me to keep the (eventual) storage half cooler than the work area. Also notice the two 3' x 3' keep-out areas for the 2-post Bend-Pak (a future purchase).

Going on the advice of someone far more experienced with Pex tubing than I am, we didn't insulate the perimeter (although it's not too late since I haven't finished grading / paving around the garage). Nor did I do anything special in the door area.

Great ideas thus far. I am wondering how many of you out here with radiant heat didn't put any insulation in the overhead door area? and has it caused a problem.

Or better yet, if you did how did you install?

 

[GeorgiaHybrid]

GeorgiaHybrid: Could you enclose a attachment or drawing of what you are speaking of?
I don't guess I understand what you are talking about. Pictures would be great!
Thanks D.J.

Does this help?
EDIT: Note!!!! You can use either the HNS or the bent plate. I just cheated and showed both of them in the same picture. You would only need them on one side

 

[armstrr]

Does this help?

this is to cover the insulation joint at the garage door, correct?

 

[GeorgiaHybrid]

this is to cover the insulation joint at the garage door, correct?

That is what his radiant heat floor man proposed. This detail will just keep it in place.

 

[mybuickgs]

this is to cover the insulation joint at the garage door, correct?

That's correct. Do you have an another idea?

 

[armstrr]

Does this help?
EDIT: Note!!!! You can use either the HNS or the bent plate. I just cheated and showed both of them in the same picture. You would only need them on one side

I asked, only because I do not follow what is happing in that picture. what is HNS? what is the material that is 6" wide?

I have the same problem coming up when i pour the driveway up to my shop...right now I have 2 5/8" polystyrene ICF foam to contend with...

 

[ConCretin]

1. Since I am putting radiant heat in the floor... is my assumption correct that the insulation between the stem wall and Floor will also serve as a perimeter expansion joint?

[IThe insulation will be more than adequate[/I]

2. What about the perimeter slab area where the overhead doors close? Do you insulate vertically along the slab in this location as well (between slab and drive way approach)? If so, Do you seal this joint?

I would opt for a 1/2" foam expansion joint material rather than the rigid insulation. It won't have quite the same R value but it will provide a good thermal break and be easier to cover.

We use what is called 'zip strip'. It has a removable strip at the top that provides a void for sealant.

The metal cover plate proposed by another poster looks pricey and would anchor the two slabs together, which could encourage cracking. persoannly I'd opt for a simpler option

3. I have read dozens of threads concerning expansion joints or saw cuts in the slab itself and still confused.

Have your contractor to saw cut the slab immediately after finishing with an 'early entry' saw, cutiing to a depth of 1/4 of the slab thickness. It's obviously critical to ensure that your radiant is well secured.

The cuts should divide your slab into panels that are as square as possible and should generally not exceed 12 x 12/I]

Hope that helps.