preparation for radiant slab heat questions

[mdshore348]

ok, well ive purchased a 2 zone radiant kit from radientec.com . ill be ready to pour by next week weather permitting, doing some last minute second guessing. - questions:

i live in the mid atlantic area , should i use 2" polystryene sheets insulation under the entire floor? some say it is only ness. to insulate the perimeter....

will the foam under my two post lift area compress under such a load when i have a 10k lb vehicle on it ? i planned on making the concrete 6" in that mounting area .or should i just avoid insulation all together in that area?

is it ness to lay plastic down first as well ?

thickness of concrete ? i will be using mesh and fibre reinforced concrete .

fyi the garage is "L" shaped , 54 ft long ,30 ft wide at bottom . half way up , 20 ft wide . 15 ft ceiling ht. .

 

[Gregdoo]

I'm not an expert, but have looked into radient for the house. Everything I've read says you want to insulate under the concrete, otherwise a lot of your heat heads into the earth and gives you no benefit.


I'm sure there are other folks better able to answer your concrete questions.

 

[muddy]

If you look at one of my posts in gallery for "detached building" and pick one of the 5 threads........there are photos of my radiant install......well, a couple. I didn't take many as I was doing an all nighter and pretty tired.
Anyways, I bought from radiantec also.......single zone....... I actually poured 2 concrete piers probably almost 2 foot deep with a 2 foot diameter for where each upright will go for future 2 post lift. Then when I routed the pex tubing I avoided those two areas.
Regarding insulation for under floor, I insulated completely using "the barrier". If you look on ebay a dealer sells it for 149.00 a roll though I paid less buying several rolls........
Shop building expenses have been high so can't afford to buy the water heater yet but all else is bought for system and hope some of this helps....... Keith

 

[krooser]

Check this out...http://www.jalopyjournal.com/forum/showthread.php?t=80594
Plastic is good if you have ANY concerns about water...