Laying the radiant floor system

Tuesday finds us putting down 5 runs of pex tubing for our radiant floor system. I have watched the DVD and read more about radiant flooring in the past 10 months than I care to admit.

My hopes are to have all of the pex laid by the end of the day on Tuesday and ready for inspection on Thursday. The only part of this that will probably hold true is the inspection on Thursday. My feelings at this point are that this to will be a bigger project than I think, and will probably take longer than I initially planned and will run into Wednesday.

Through deduction today I have learned that our raising will probably not occur until after Thanksgiving. I went out to the web site of the company who is constructing our frame. They post their upcoming raising on their website.

I had written this first part just prior to going up on Tuesday to lay the pex tubing. Since then a lot has happened.

First off I did find out that the current schedule puts us at raising the frame the week of the 27th right after Thanksgiving weekend. This gives us a chance to take a bit of a breather and get things lined up and prepared for the raising and for applying the SIPs.

Now on to the pex tubing. We left early Tuesday morning, and after a quick stop at the county office to pick up another set of red lined prints we were off to Williams.

Upon arriving, the concrete company was digging a couple of piers and adjoining footing that were initially overlooked by them. They were out there for about 2 hours finishing up digging, making final preparations for Friday's pour and setting the sonotubes.

We wasted no time and got the pex tubing un-boxed and stuck a couple of rolls in the truck to warm them up to make them a little more flexible. My wife and son came up to help which made all the difference in the world having three people there helping.

So with the plan in hand as to the pattern the Radiant Floor company had drawn out for us to follow we made the first connection to the manifold and took off putting done the pex. The first roll took about 45 minutes and the remaining four just got quicker. I am happy to report that the whole process went flawless!!
Then the moment of truth came when we went to pressurize it. They said that this may take a little while and they were right. The compressor took a while to bring the pressure up to 50 pounds. Once that was reached we continued to do some final tieing down and watched to make sure the pressure held.

For about the first hour and a half it held steady and then as the area began to get shaded it slowly dropped which was to be expected. By the time we left it had dropped about 5 pounds, again this is to be expected.

So fortunately the whole thing took about 4 hours. We were all amazed how easy the whole process went. We were careful to keep our turns from getting to tight so as not to kink the pex. This would then require a splice which I really did not want to see happen. We also added about a five foot piece of pex at the manifold with the end taped for a sensor that will be fed down in to the pex prior to start up. This acts as a thermostat for the system to control the temperature of the floor.





Also while my wife and son were putting the finishing touches on the floor, I picked up some 1" foam insulation with foil back vapor barrier. I was not comfortable leaving the pier area within the slab coming in direct contact with the stem walls. I also did not want the 2" Styrofoam there either due to the fact that these areas were going to be supporting the 8x8 posts and I did not want to compromise any support there. The one inch allowed me to do make a break between the slab and the stem wall and not compromise support.