I recently received literature from BASF Polyurethane Foam Enterprises LLC with regards to their closed-cell polyurethane spray foam insulation, COMFORT FOAM®. What drew me to their product was their initial caption, “[a]re you wasting as much as 40% on your energy bill?” How many of you can relate to throwing money out the window every month from your leaky home? According to the Department of Energy, you can reduce your heating and cooling costs up to 30% by proper insulation and air sealing. BASF’s COMFORT FOAM® goes a step beyond to create a higher level of comfort and reduction of energy costs than traditional insulation.
I am no stranger to preaching the benefits of spray foam insulation since my own home was sprayed with Icynene®, an open-cell spray foam insulation. My house is a lean, mean energy saving machine with a geothermal system and thick foam throughout the basement, first and second floor exterior walls, and garage walls. When I first wrote about how much I loved my Icynene®, one of my commenter and now friend, Gary of Virstar Geothermal Energy HVAC Group Enterprises, extolled the benefits of closed-cell spray foam insulation. (You can read his and other comments here. The discussion is quite interesting.)
What Are COMFORT FOAM®‘s Attributes?
The Company manufactures two different types of closed-cell spray insulation: COMFORT FOAM® 178 (typically for colder climate) and COMFORT FOAM® 158 (for warmer climates.) According to BASF, their 2 lb. closed-cell spray polyurethane foam insulation has the following attributes:
- The Company’s COMFORT FOAM®158 has an R-value of 6.6 per inch and the COMFORT FOAM® 178 has an R-value of 6.7 per inch compared to an open-cell spray foam, which has an R-value on average of 3.5 per inch.
- Outstanding air sealing ability.
- Increased structural strength
- Improved comfort with reduced drafts
- Better Indoor Air Quality
- Environmentally responsible with VOC-free and zero-ozone depleting blowing agent technology
- Inhibit the growth of mold since it eliminates air movement in the wall cavity, and thus decreases the possibility of condensing surfaces which lead to moisture.
- Closed-cell foam is approved by FEMA for use in flood prone areas.
- There is no formaldehyde in the Foam unlike some fiberglass insulation.
- The Foam meets class one fire and smoke characteristics.
Wondering on how foam is sprayed into the wall? Watch this short video .
Where can COMFORT FOAM® be installed?
COMFORT FOAM® can only be used where there is an open wall cavity such as in new construction or renovation as well in an unfinished attic or crawlspace. It can not be blown in a wall cavity in which drywall is affixed to it. According to the Company’s technical detail,
“[p]olyurethane foam systems should not be left exposed and must be protected by a minimum 15-minute thermal barrier or other code-compliant material as allowed by applicable building code(s) and Code Officials. Building Codes provide guidelines representing minimum requirements.”
The Foam would be required to be enclosed by drywall or other fire retardant barrier.
What’s the difference between closed-cell and open-cell foam insulation?
Many of you are wondering what the difference between open and closed-cell foam insulation. According to the Company,
“[t]here are three major differences. First, BASF Polyurethane Foam Enterprises uses the versatility of chemistry to offer a closed-cell content of greater than 90 percent for all of its formulations, and open-cell foams commonly used as insulation systems have approximately 60 percent open-cell content. Second, closed cell content offers an R-value of over 6.0 per inch and open cell offers between 3.0 and 3.6 per inch. Third, closed cell foam is virtually impermeable to air, while open cell foam allows far more air and vapor into the house interior.”
I found it interesting that the Company sells ENERTITE®, an open-cell polyurethane foam insulation and compares it to their COMFORT FOAM® closed-cell insulation along with traditional fiberglass, and blown-in cellulose. (See chart above.) No one could claim that BASF is making false marketing claims about open versus closed-cell since it sells both.
The one line item on the chart that caught my eye was the absorption of moisture. The closed-cell absorbs less than 4% of value to volume compared to the open cell, which absorbs more than forty percent value to volume. As stated above, the presence of moisture can lead to mold. In addition, in order for the open-cell to be considered an air barrier, 5.5″ inches of foam must be installed in the walls, whereas the closed-cell reaches approved air barrier level at 1.5″ of foam.
Why didn’t I install closed-cell in my own home? Contractors charge more for installing closed-cell versus open-cell. In addition, I was warned five years ago that it off-gassed. Since building a nontoxic house was the most important aspect of my building project, I was too frightened by the possibility of this statement being true. Given BASF’s nontoxic stance, I may have reconsidered the higher cost given the benefits of closed-cell insulation.
Will spraying foam insulation on the underside of the roof shorten the life of my roof tiles?
One question I have always had about spraying the roof rafters is will it shorten the life of the roof since the roof can not breathe? In my own house, I have one section in which the rafters were sprayed. I noticed that it is the last area of the roof to dry out. My 2nd floor ceiling is full of foam and my recessed lights are all air tight. I am in New Jersey so we have cold winters and humid summers. So, I posed the question to the Company. I received the following response from Jim Andersen, a Company Manager of Application and Training , who is a seasoned 35-year plus veteran in the spray foam industry as a contractor, distributor and now a manufacturer of materials:
“The [sic] article was written by Mark Graham, Technical Director for the National Roofing Contractors Association (NRCA) which is the leading roofing industry trade association. It should help clear up the question that when using either open-cell spray foam or closed-cell spray foam to unvented attic applications, it is possible to obtain asphalt based shingles and maintain a manufacturers warranty for the shingles. BASF supports the conclusions explained by Mark Graham in his article. Listings are updated each year and published in the NRCA Steep Slope Roofing Materials Guide available from www.nrca.net for a fee. This book will list those manufacturers that offer shingle warranties over insulated roof decks or non vented attic applications.
As far as the question of spraying foam to the underside of the roof deck, will it shorten the life of your roof? This is a hard question to answer. The first major question is where is the geographic location of your home and the color of the roof? Locations in northern climates which dark colored roofs generally will not have an adverse impact to the life of the roof. Steep sloped roofs may last longer than low sloped roofs. Hot climates with dark colored roofs generally will not last as long as light colored roofs. When we add insulation, one must ask how much and what is the overall performance of the insulation.
Uninsulated roof decks will generally warm and cool as does the outside temperature. When adding insulation, the objective is to keep the attic air temperature controlled or conditioned. When any type of insulation is added to the underside and the vents closed off, this air space is called “conditioned air space”. In other words, it should be about the same temperature as our inside house environment. The heat or cold is kept out of this area because the insulation performs a function. Most shingle warranties are for 10, 15, 20 or more years in duration. Most warranties are pro rated which means the value decreases with time. In my opinion, the use of BASF open-cell or closed-cell foams for underside applications per building code requirements will not have an adverse effect on the life of the roof. This is supported by several manufacturers who are willing to offer warranties for their shingles when used in this non vented application.”
In any event, check to make sure spraying the underside of your roof does not void your roof warranty.
What are your thoughts on the subject?
Has anyone used closed-cell spray foam insulation?
Has anyone installed closed-cell insulation in their home, and if so, what has been your experience? If you are a contractor, have you installed both closed and open cell insulation, and if so, what has your experience been? Is installing closed-cell insulation overkill or a good bang for the buck?
Special thanks to Katharine Davino, Marketing Operations at BASF PFE for her assistance in this article. All charts and photos are courtesy of BASF Polyurethane Foam Enterprises LLC.