radiant floor heat transfer plates

FredDrone

my home has basement access to the underfloor joists and subflooring. My question to the forum is whether I SHOULD or NOT cut the the plates from their 4' lengths in order to achieve my heating needs in the different rooms of my home. Will the uniformity of heat be achieved, or will the floor have "Hot spots" that I will regret later. Also, "ALL THOSE NAILS"!!!

hcpatel78

Hi,
You can cut those plate if you want to accommodate length. I prefer to cover as much area as possible with plates for even heating. I used miter saw with carbide blade to cut those plates. Plates made with t aluminum will cut with that very easily.
Yes you have to remove nails. you can follow my topic and you will get lots of information from that discussion. Lots of pro commented and guided me through out my project and I am so much thankful to them after having best feel of the heating my house in last winter.
https://forum.heatinghelp.com/discussion/179216/need-advise-confirmation-for-underfloor-between-joist-radiant-installation-northern-nj-zone-5/p1

STEVEusaPA

If you cut them, file the edges smooth, especially anywhere that touches the tubing.

ewang

I used an oscillating tool with a carbide blade to cut the nails - no sparks or smoke.

Derheatmeister

If you hate the nails and do not want to crawl around in a Crawl space , make Swiss Cheese out of your Joists you may consider a flooring system such as Viega Climate Panel, It only adds a 1/2" height to the floor, has a better heat transfer and is much easier to install..

https://www.viega.us/en/products/Catalog/Heating-and-Cooling-Systems/Heating-and-Cooling-Solutions/Panels-Plates-Tracks-and-Mats/Viega-Climate-Panel-2810-2US.html

Dave H_2

Whenever I go to cut a plate, cut it in half only. Adjust with the spacing from end to end to make it so. However with that being said 8-10" would be the max.
Remember, no plates on the ends of the joist cavity, about 8-10" again, you always want the pex to exit the end of the plate, not the middle

Dave H.

hcpatel78

Dave H_2 said:

Whenever I go to cut a plate, cut it in half only. Adjust with the spacing from end to end to make it so. However with that being said 8-10" would be the max.
Remember, no plates on the ends of the joist cavity, about 8-10" again, you always want the pex to exit the end of the plate, not the middle

Dave H.

Dave any specific reason for the tube exiting at the end of the plate?

Dave H_2

Pex will expand and contract as it heats up and cools down not radially but linearly. It will become longer and shorter. If you exit a plate in the middle, it can eventually work its way out of the plate and then just be hanging there. At the end of the joists, that is where a wall typically is above. If you feet are in that area walking, that means you are using the wall to hold you up and at that point, a warm floor is not your priority!
The floor may be a degree or two cooler in those area but still going to heat the space.

Derheatmeister

Dave H_2 said:

Pex will expand and contract as it heats up and cools down not radially but linearly. It will become longer and shorter. If you exit a plate in the middle, it can eventually work its way out of the plate and then just be hanging there. At the end of the joists, that is where a wall typically is above. If you feet are in that area walking, that means you are using the wall to hold you up and at that point, a warm floor is not your priority!
The floor may be a degree or two cooler in those area but still going to heat the space.

As Dave mentioned it most likely will work...However the Delta T will be more that just a degree or two.
Here is a Link to some Infrared camera images of different "Plates"

https://radiantdesignandsupply.com/theheatexchanger/2013/3/4/comparative-infra-red-study-of-heat-transfer-plates

Make sure that you drill a Large enough hole and that the tube is installed so that it does not rub on the floor joist,otherwise you may have noises every time the heat comes on...