Foam Plastic / Thermal barrier / Interior finish

[darcar]

2006 IRC Section R314 Foam Plastic

An owner built a new home in our jurisdiction, and the owner has sprayed foam to the underside of the vaulted ceiling and left it exposed. The only product applied to the foam is a "Thermal barrier paint" DC 315 https://www.sprayfoamdirect.com/products/component/page,shop.product_details/flypage,shop.flypage/product_id,48/category_id,7/manufacturer_id,0/option,com_virtuemart/Itemid,1/vmcchk,1/ http://www.painttoprotect.com/UL1715_and_Ignition_barrier_cut_sheet.pdf

Is your jurisdiction allowing this? This particular paint has a UL 1715 listing.

 

[righter101]

It appears to meet the requirements spelled out in R316.6.

I would double check the thicknesses of foam against the mfgs claim.

 

[rshuey]

The paint may be a thermal barrier, but make them show you the assembly. The items allowed for a thermal barrier without showing an assembly are clearly spelled out.

 

[Francis Vineyard]

Aware that R314.4 invites that the thermal barrier remains in place for 15 minutes; though the coating may remain on the insulation the foam falls from the ceiling in half the time. It's your call;

"Such materials are not classified as equivalent thermal barriers but may be used as an alternative assembly provided it has been approved by the code authority having jurisdiction."

source: http://idimn.com/wp-content/themes/idi/pdf/spray-foam/materials/BaySeal/AY-126.pdf

 

[Architect1281]

Most all of the spray Polyurethane expansive foams have an ESR approval report that lists the requirements

for moisture and thermal exposed surface barrier. and each one has a product that is tested on that foam.

I do not alow any applied products to an in place foam unless it is listed on the ESR Report.

here is the list bi CSI section 072100 on the es repots http://www.icc-es.org/reports/index.cfm?csi_num=07 21 00&view_details

PS sometimes the designer, installer, owner, and perticularly the salesperson are amazed to find such a document.

I continue to hear "But the sales rep said"........as opposed to the sales rep read.

 

[mtlogcabin]

UL 1715 Thermal Barrier

o (88.88 sq. ft./gal @ 18 mils wet and 12 mils dry) coverage rate of 1.136 gallons (4.3 L) per 100 square feet (9.3 m2)

 NFPA 286 (AC377) Attic Crawl Space Ignition Barrier

o (130 sq. ft./gal @ 12 mils wet 8 mils dry) coverage rate of .77 gallons (2.9 L) per 100 square feet (9.3 m2)

How do you know it is applied at the proper thickness. It is a special inspection under the IBC

 

[Architect1281]

reason No. 5 why its not a good idea to expose plastic