Closed cell spray foam... UNDER a concrete slab?
HTML-код
- Опубликовано: 14 июл 2024
- Watch our entire free catalog of content:
buildshownetwork.com/
Sign up for the BSN News letter!
buildshownetwork.com/newsletter
On this episode Wade will walk you through using closed cell spray foam under a concrete slab. Wade's company has been using this application for about 8 years and it has become almost their go-to application for insulating under a slab. What Wade likes about this application is:
- Just 2" of closed cell spray foam yields an R-14
- It's monolithic so its continuous with no joints or seams
- It is an effective moisture barrier
- Provides an excellent vapor retarder
- Is an excellent radon blocker
- Has a perm rating of less than 1
- Bonds exceptionally well to crushed stone 
Наука
Great information.
No mention of in-floor radiant heat? Obviously running saw cuts could cause a fairly major issue, but in-slab heat over 2” insulation is a winner. I love the idea of spraying it, maybe zip-strips? I know sometimes it’s hard to keep those perfectly straight….
Would love to know material thicknesses you recommend for such a slab? How much base, 2” closed cell, then how much concrete of the 3500-4000psi material? Love the approach- build it right from the onset, never need to fix it later.
We are using a similar method for our fiber reinforced slab. We are building in a radon prone area. Have you found any documentation for thickness and foam density for inspectors who are concerned about radon / vapor barriers? Thanks Jason G.
I'm thinking it's time for robotic spray foam application. Or at the very least a spray cart so the foam is applied perfectly without any spray skill needed.
I'm thinking the same thing. Like a big portable 3D printer.
Would you consider this with radiant floor heating?
Placing foam under the concrete, can that help with preventing pipes from freezing?
What do you think for a 1-storey bungalow, do you think you could use spray foam insulation instead of concrete? It has a compressive strength of 50 PSI, and my loads on the exterior wall on the foundation are 11 PSI.
Hold on, is that an elf spraying the foam?
Lol!
Is Crush an run stone the stone your using?
What about the closed-cell pulling away from some surfaces after curing? Less of a problem than 2" XPS + tape? (Also, are you using a sheet of poly under the slab as well?)
From my research (check out Spray Jones), proper installation will not peel away, and closed cell negates the needs for poly.
@@CourtneySchappert Understood. The issue is finding "proper installation".
Closed cell foam over 1" thick is a vapor barrier. Not the case with open cell foam.
Did you mean to say "fiber mesh straight from the factory" @3:39? So you aren't laying down wire mesh? Thanks
He’s referring to Fibermesh admixture in the mud not the wire I think - good question tho
@@jaredlogan1676 wanted to make sure. I have fiberglass additive in my garage floor. One unexpected benefit was not having to add sand to the epoxy floor as the exposed fiberglass balled up to form little nubs for wet traction. We didn't want to add too much texture as it would be more difficult to mop and sweep.
so wade- to review 6" of crushed stone (not sure if this is a specific universal description ? then 2:clsoed cell spray fam (at what rated compressive strength?) NO plastic vapor barier/Stego tc ?, , how do you thermally uncouple at edges ? take the spray foam up the wall a few inches ?
Closed cell foam over 1" is a vapor barrier. Not the case with open cell foam.
Check this video out - ruclips.net/video/brvjcUtiwtM/видео.html
He runs it up the wall
Look at the shoes of spray guy. :)
if the concrete slab cracks which is inevitable, is it assumed the spray foam underneath has also cracked?
What about 2 inches of rigid foam (rough cut) and spray foam on the seams and corners and small fill areas?
What is the price in US of closed cell dedicated under slab?
Lol
Around $1 to $2 per board foot of foam (12×12×1)
I'm sure you know that fibermesh is not a replacement for steel reinforcement. Fiber reduces shrinkage cracks but does not increase strength.
I'm quite sure he knows that
Which is fine if the additional strength is unnecessary for the application.
Many tilt panel warehouses forego the wire mesh these days and with a 6 in slab using fiber reinforcement have no issues with forklift traffic, etc.
Your guy's moving too fast to get the thermal expansion the product requires. It'll work but its wasting material and reducing efficiency.