Joist trak with spray foam vs quik trak

zalbrecht

I've read some articles on this on here but no one really discussed this strategy to mitigate heat loss. Would the performance of joist trak with a 4 inch spray foam layer on top of it be at least as effective as quik trak?

kcopp

I would not do the spray foam. It makes issues down the road a real pain. Fill the bay w/ Rockwool and you have a great insulator, Less dust than fiberglass plus the fire retardancy and sound dampening as a bonus.

Zman

Are you asking about downward heat loss to a conditioned space below? That I would not be super concerned about. Fiberglass insulation or rockwool will work fine. Most people overlook the importance of rim joist and slab edge insulation. I would spend the extra money there where the majority of the heat loss happens.

EdTheHeaterMan

The last home I lived in, I ran PEX between the floor joist supported by aluminum plates. There was an addition and the masonry contractor was supposed to provide a crawlspace. With the grade of back of the home being uncooperative, the contractor convinced me that a slab on grade was better. I agreed and placed 2" foam below and perimeter then put in 3/8" PEX for future use. Two years later I installed the boiler. Then I installed the PEX as described above in the main part of the house. The addition included foam insulation for the addition and the attic and floor of the main home. After 2.5 years the insulator called me to ask if he could finish the floor insulation. I promptly finished the PEX install and had the floor insulation completed.

I have to say the slab floor heat is more effective, but the aluminum plate under the floor with foam below it is quiet and comfortable. Not enough to heat the house below 20° outdoor temp., but the old gas furnace is still there for when it gets that cold.

TAG

Are there any real world studies of Quik Track? Have never seen an install - always questioned the ability of the PEX to transfer heat to the lower plate ... the transfer caulk seems problematic and there is only a small contact point at most. I would not assume that it's inherently superior to the underfloor plates .... My guess is it's not.

Joist Trak type systems do work. I use spray foam in my projects and while the PEX will become encased in any that has to come down an outside wall ... I never foam the panels directly.

IMO both systems need insulation under the subfloor ... every system does. Also -- I always use 5/8 rock and insulate all the interior walls. Regular fiberglass batts are all you need in the wall cavity ... Rockwool is in my opinion a superior insulation product as it does not allow air movement ... but -- that's not a concern with interior walls.

I have spray foamed under Warmboard -- but that was for fire safety. I wanted a layer of foam to protect a bonus room from smoke. That may be a system if building with an open crawlspace.

Alan (California Radiant) Forbes

The closer you can get the tubing to the actual living space the better. Both Uponor's Quik Trak and Viega's Climate Panel are ideal if you are installing a new floor and are looking for the minimum thickness addition as they are both 1/2".

However, if you want to keep your existing flooring, then many of the underfloor products will get you the heat that you want. Personally, I like Ultra-Fin as you can exceed the 120F maximum water temperature for underfloor plates.

Whatever product you use, do the heat loss calculations and work within the products guidelines for water temperature, spacing, insulation requirements, etc.

ethicalpaul

My feet tell me that quik trak transfers heat real nice

TAG

Alan (California Radiant) Forbes said:

The closer you can get the tubing to the actual living space the better. Both Uponor's Quik Trak and Viega's Climate Panel are ideal if you are installing a new floor and are looking for the minimum thickness addition as they are both 1/2".

However, if you want to keep your existing flooring, then many of the underfloor products will get you the heat that you want. Personally, I like Ultra-Fin as you can exceed the 120F maximum water temperature for underfloor plates.

Whatever product you use, do the heat loss calculations and work within the products guidelines for water temperature, spacing, insulation requirements, etc.

I guess the small contact point on top where the PEX touches the finished floor would be a spot where the subfloor plates can't match. The better plates really grab the PEX for very good contact -- the AL on the bottom of the Quick Trak looks rather thin -- and the heat still has to pass through what is really a 1/2 subfloor.

Look much less expensive vs the Warmboard R ...

TAG

ethicalpaul said:

My feet tell me that quik trak transfers heat real nice

How tight does the plywood grove capture the PEX ? Knowing how caulks age over time -- wonder if with any degradation of the material the heat transfer may drop?

Not having to use different temp water for different systems is nice and some don't have the same output at low temp water.