Thread: Blue spray foam

Inspected a home today. Found this stuff on the exterior wall which also happens to be the furnace roam.

I am of the opinion that all foam irrespective of color should be covered. Am I correct in thinking this is a defect?P1000771.JPG

Why should it be covered? Covered with what?

Originally Posted by Scott Patterson

Why should it be covered? Covered with what?

This is the starting point, then go to R316.5 for various exceptions and options to see what is needed/permitted.
- R316.4 Thermal barrier.
- - Unless otherwise allowed in Section R316.5 or Section R316.6, foam plastic shall be separated from the interior of a building by an approved thermal barrier of minimum 1/2 inch (12.7 mm) gypsum wallboard or a material that is tested in accordance with and meets the acceptance criteria of both the Temperature Transmission Fire Test and the Integrity Fire Test of NFPA 275.

Not an easy answer with the information known (will likely need to be covered if the information on the foam is not available).

Hi Guys,

I have always been told that because the foam is flammable is why it should be covered (with gypsum board AKA drywall) The argument I have been given is that drywall has some fire resistant properties that will slow a burn. But spray foam is highly flammable.

What does the rules say about the blue spray foam?

Thanks,

Michael

Originally Posted by michael Rodney

What does the rules say about the blue spray foam?

I gave you the IRC rules - some of them, the sections which follow the one I posted are quite long.

You are in Canada, what does the Canadian code say about exposed plastic and foam (the color of the plastic and foam does not matter)?

In my area the AHJ's only want foam covered if it is in a habitable area. I see it all the time in crawlspaces, basement storage rooms, cold rooms, etc. I'm betting that the foam has a lower flame spread factor than most anything else in the home.

The color of the foam I believe is brand specific.

Originally Posted by Scott Patterson

In my area the AHJ's only want foam covered if it is in a habitable area.

I'm guessing that the AHJ either has not kept up with the IRC or has adopted amendments to it (some places gut the IRC when adopting it).

This is from the 2012 IRC: (bold is mine)
- R316.5 Specific requirements.
- - The following requirements shall apply to these uses of foam plastic unless specifically approved in accordance with Section R316.6 or by other sections of the code or the requirements of Sections R316.2 through R316.4 have been met.
- - R316.5.1 Masonry or concrete construction.
- - - The thermal barrier specified in Section R316.4 is not required in a masonry or concrete wall, floor or roof when the foam plastic insulation is separated from the interior of the building by a minimum 1-inch (25 mm) thickness of masonry or concrete.
- - R316.5.2 Roofing.
- - - The thermal barrier specified in Section R316.4 is not required when the foam plastic in a roof assembly or under a roof covering is installed in accordance with the code and the manufacturer’s installation instructions and is separated from the interior of the building by tongue-and-groove wood planks or wood structural panel sheathing in accordance with Section R803, not less than 15/32 inch (11.9 mm) thick bonded with exterior glue and identified as Exposure 1, with edges supported by blocking or tongue-and-groove joints or an equivalent material. The smoke-developed index for roof applications shall not be limited.
- - R316.5.3 Attics.
- - - The thermal barrier specified in Section R316.4 is not required where all of the following apply:
- - - - 1. Attic access is required by Section R807.1.
- - - - 2. The space is entered only for purposes of repairs or maintenance.
- - - - 3. The foam plastic insulation is protected against ignition using one of the following ignition barrier materials:
- - - - - 3.1. 11/2-inch-thick (38 mm) mineral fiber insulation;
- - - - - 3.2. 1/4-inch-thick (6.4 mm) wood structural panels;
- - - - - 3.3. 3/8-inch (9.5 mm) particleboard;
- - - - - 3.4. 1/4-inch (6.4 mm) hardboard;
- - - - - 3.5. 3/8-inch (9.5 mm) gypsum board; or
- - - - - 3.6. Corrosion-resistant steel having a base metal thickness of 0.016 inch (0.406 mm);
- - - - - 3.7. 11/2-inch-thick (38 mm) cellulose insulation.
- - - The above ignition barrier is not required where the foam plastic insulation has been tested in accordance with Section R316.6.
- - R316.5.4 Crawl spaces.
- - - The thermal barrier specified in Section R316.4 is not required where all of the following apply:
- - - - 1. Crawlspace access is required by Section R408.4
- - - - 2. Entry is made only for purposes of repairs or maintenance.
- - - - 3. The foam plastic insulation is protected against ignition using one of the following ignition barrier materials:
- - - - - 3.1. 11/2-inch-thick (38 mm) mineral fiber insulation;
- - - - - 3.2. 1/4-inch-thick (6.4 mm) wood structural panels;
- - - - - 3.3. 3/8-inch (9.5 mm) particleboard;
- - - - - 3.4. 1/4-inch (6.4 mm) hardboard;
- - - - - 3.5. 3/8-inch (9.5 mm) gypsum board; or
- - - - - 3.6. Corrosion-resistant steel having a base metal thickness of 0.016 inch (0.406 mm).
- - - The above ignition barrier is not required where the foam plastic insulation has been tested in accordance with Section R316.6.

Now, if the foam plastic meets R316.6, that changes the above requirements as stated in the above:
- R316.6 Specific approval.
- - Foam plastic not meeting the requirements of Sections R316.3 through R316.5 shall be specifically approved on the basis of one of the following approved tests: NFPA 286 with the acceptance criteria of Section R302.9.4, FM4880, UL 1040, or UL 1715, or fire tests related to actual end-use configurations. Approval shall be based on the actual end use configuration and shall be performed on the finished foam plastic assembly in the maximum thickness intended for use. Assemblies tested shall include seams, joints and other typical details used in the installation of the assembly and shall be tested in the manner intended for use.

The "actual end-use configurations" is key as many of the test were done withe the foam plastic under a horizontal surface or above a horizontal surface - as soon as the surface is no longer horizontal, and especially when the surface is vertical, any test done with the foam on or under a horizontal surface is no longer applicable and the test is invalid to the application because the "actual end-use configuration" does not match the test configuration. Many of the foam companies are doing testing with slope surfaces (which would still not address vertical surfaces unless also tested on vertical surfaces) to show their products will still meet the criteria requirements.

I would not want to not write up exposed foam plastic, especially such as in the photo - at the very least I would recommend that the plastic be checked for compliance with local requirements - typically the contractor who installed it, or any other contractor who installs spray foam will be able to get the specs on that plastic.

That lets everyone else know that there "may be a risk" and that "they should have it checked out" (which is usually a relatively simple thing to do). When the foam checks out, no problem, and when the foam does not check you ... You da man! ... And they will call you again.

Once you see the same foam plastic a few times and find out that "it checks out", then it is up to you if you want to take the full responsibility for making the call of not mentioning it. Especially is there is a fire and the foam is part of the fire area ... I would not want to get that call late at night ... or any other time either.

You guys make those calls, the fire investigators just point to the foam as a source of feeding the fire or not.

Three Massachusetts Home Fires Linked to Spray-Foam Installation | GreenBuildingAdvisor.com

Foam: Fire Hazard and Fire Barrier | Monolithic

Originally Posted by Jerry Peck

...what does the Canadian code say about exposed plastic and foam?

Ontario Building Code 332 12

9.10.17.10. Protection of Foamed Plastics

(1) Except as provided in Sentence (2), foamed plastics that form part of a wall or ceiling assembly in combustible construction shall be protected from adjacent space in the building, other than adjacent concealed spaces within attic or roof spaces, crawl spaces and wall assemblies, by,

(a) one of the finishes described in Subsections 9.29.4. to 9.29.9.,

(b) sheet metal mechanically fastened to the supporting assembly independent of the insulation and having a thickness of not less than 0.38 mm and a melting point not below 650°C provided the building does not contain a Group C major occupancy, or

(c) any thermal barrier that meets the requirements of Clause 3.1.5.12.(2)(e).

From my local CBO:
Hi Jim,
The current code requires that all spray foam insulation / polystyrene insulation is to be covered with one of the flame spread products mentioned in the code. It’s the fumes and volatility of the ignited foam that kills the occupants of the building.