Ok, i’m planning on building in Northwestern Wisconsin, near the shores of lake superior. My house is going to have infloor heat in it.
I would like to pour a slab foundation with infloor heat tubes in it this fall and leave the slab over the winter. This would allow me to get an extremely early start on building next spring in comparison to doing site prep, rough in plump, form, and pour in the spring.
Has anybody out there done this?? Should I be concerned having the heat tubes in the slab, considering the frost in the ground???
I thought about covering it with heat blankets and straw. Would this be enough?? Are there better methods or materials to do this???
Thanks for the help!!!
upnorth8
Replies
Your going to fill the tubes for the pour, use the radiant antifreeze and leave them filled during the winter.
There shouldn't be any issue leaving the slab and pipes in place. Either leave them filled with antifreeze (rated for the pex you're using -- potable if this is going to be connected to the potable water system) or blow them out. One thing to consider is sleeving the exposed ends of the tubes so they don't get damaged during the winter. You can either build a small structure out of scrap 2x and plywood/osb to protect them, or slip an appropriately sized pvc pipe around them into the slab slightly and then after the pour glue on enough of a "riser" to completely cover the exposed pipes.
Most of the pex isn't rated for exposure to UV, and you also don't want them flailing around in the wind/snow/critters/visitors to get damages. The last thing you want is to have them broken off at slab level and have to be in there with a chisel to get enough room to make a new connection.....
Depending on what the soil and moisture conditions are under your slab when it freezes, you could very likely get frost heaving and random cracking in your slab unless it is well reinforced and has crack control joints cut into the slab.
Cutting control joints with pex in the slab is a whole other issue, which you should study!
The most important thing is to try and establish a well drained base. As insulation, straw is pretty effective if applied thick enough.
Remember " The gales of November come early"