Seamless &
Flexible

Seamless: Polyurethane foam is applied as a liquid, creating a single monolithic membrane that covers the entire roof. There are no seams or joints, the source of the majority of leaks in traditional roofs.

Flexible: 
The foam can be sprayed onto virtually any surface, irregularly shaped roofs and protrusions are readily taken care of.

Lightweight &
Sustainability

Lightweight: Foam roofing typically weighs around 50 lbs. per square, versus 800 lbs. for a built-up roof and 100 lbs. for ballasted single-ply roofs.

Sustainability: Foamed roofs require a minimum of upkeep, creating little waste and have an indefinite lifespan.

Thermal
Insulation

Thermal Insulation: SPF has the best insulating properties available for commercial construction today.

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Apr 7, 2012 |
About Spray Foam,  |
Archie Umberger

Closed Cell vs. Open Cell Foam


Tags: spray polyurethane foam insulation, air barrier, moisture barrier, closed cell foam insulation, open cell foam insulation, wall foam, energy savings, mold prevention, foam cans, seal cracks, stops air and moisture infiltration, high R-value, Closed Cell S

What is the Difference between Open-cell and Closed-cell Polyurethane Foams? 

This may be one of the most important pages on the website if your interest is in spray foam insulation. When it comes time to actually put the foam product in your home or commercial building structure, you must identify whether you will use 0.5 lb./cu. ft., open cell foam, or 2.0 lb./cu. ft. closed cell foam. This makes a big difference in cost, application methods, and performance. 

With the open-cell vs. closed-cell issue, there are two major factors to understand and consider. The first is the nature of the foam. It is either open-cell foam, where the tiny cells of the foam are not completely closed. They are broken and air fills all of the “open” space inside the material. This makes the foam weaker or softer feeling than closed-cell foam. 

Closed-cell foam differs in that all of its tiny foam cells are closed and packed together. They are filled with a gas that helps the foam rise and expand and become a greater insulator. These cells can be formulated to obtain many characteristics, the most common being size and density. 

Density is measured by weighing one solid cubic foot of foam material. Open cell foams typically weigh in at 0.4 to 0.5 lb./cu. ft. Closed cell foam for insulation applications range in density from 1.7 lb./cu. ft. to 2.0 lb./cu. ft. Roofing applications typically use a 2.8 to 3.0+ lb./cu. ft. to support traffic and loads better. The higher the density the foam, the heavier, or stronger it becomes. Some polyurethane foams are molded into decorative interior molding and painted or stained for a simulated wood effect. These “higher density” foams are typically in the 30 lb./cu. ft. to 40 lb./cu. ft. density range. 

The advantages of closed-cell foam compared to open-cell foam include its strength, higher R-value, and its greater resistance to the leakage of air or water vapor. The disadvantage of the closed-cell foam is that it is denser, requires more material, and therefore, is more expensive. Even though it has a better R-value, typically the cost per R is still higher than open-cell foam. The choice of foam can also be based on the requirements for the other performance or application specific characteristics such as strength, vapor control, available space, etc. Open-cell SPF has an R-value around 3.5 per inch and typically uses water as the blowing agent. Closed-cell SPF has an R-value of around 6.0 per inch (aged R-value) and uses high R-value blowing agents. 

Both types of foam are commonly used in most building applications and the choice for which to use can depend on many of the factors discussed above. Some foams are inappropriate in specific applications. For example, you typically would not use open-cell foam below grade or in flotation applications where it could absorb water; this would negate its thermal performance because water is a poor insulator compared to air. Closed-cell foam would be a good choice where small framing sizes need the greatest R-value per inch possible. Closed-cell foam would be used for roofing applications.

Blog Posted: Apr 7, 2012
Posted by: Archie Umberger
President Foam Kote, Inc.
(713) 943-0672

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Sprayed Polyurethane Foam is a combination of isocyanate and polyol. These two components are fed through a proportioner which heats then pumps the two separate components to the spray gun, where they are mixed and sprayed onto the substrate. Because it is sprayed onto the roof as a liquid, it forms a single continuous structure that is seamless and very stable. SPF requires a clean surface for proper application. It must be dry, free of contaminants like oil, and properly fastened to the substrate in accordance with the proper building codes.

Polyurethane Foam Services

Foam Kote Inc. will facilitate an estimate and provide advanced insulation for your individual needs. We specialize in such industrial needs as tanks, tanker trailers, coolers, vans, rail cars, buoys, barges, and skids.  Polyurethane spray foam provides superior thermal performance to minimize hot and cold spots that can influence the efficiency and comfort of a building or home. It also contributes to the structural integrity of your walls while acting as a secondary moisture vapor barrier to assist in the minimization of the risks of moisture intrusion in the wall cavity.

Benefits of Spray Foam Insulation

  • Stops air and moisture infiltration
  • Makes your home more comfortable
  • Saves on energy costs
  • Adds strength to the building structure
  • It is permanent and will not sag
  • Keeps dust and pollen out
  • Eliminates Ice Daming
  • Improves Air Quality
  • Reduces capacity requirements, maintenance and wear of HVAC equipment
  • Meets all building codes

Closed Cell vs. Open Cell Foam

What is the Difference between Open-cell and Closed-cell Polyurethane Foams? 

This may be one of the most important pages on the website if your interest is in spray foam insulation. When it comes time to actually put the foam product in your home or commercial building structure, you must identify whether you will use 0.5 lb./cu. ft., open cell foam, or 2.0 lb./cu. ft. closed cell foam. This makes a big difference in cost, application methods, and performance. 

With the open-cell vs. closed-cell issue, there are two major factors to understand and consider. The first is the nature of the foam. It is either open-cell foam, where the tiny cells of the foam are not completely closed. They are broken and air fills all of the “open” space inside the material. This makes the foam weaker or softer feeling than closed-cell foam. 

Closed-cell foam differs in that all of its tiny foam cells are closed and packed together. They are filled with a gas that helps the foam rise and expand and become a greater insulator. These cells can be formulated to obtain many characteristics, the most common being size and density. 

R Value Fairy Tale

THE MYTH OF INSULATION VALUES
by David B. South

One of the fairy tales of our time is the "R-value." The "R-value" is touted to the American consumer to the point where it has taken a "chiseled in stone" status. The saddest part of the fairy tale is the R-value by itself is almost a worthless number.

It is impossible to define an insulation with a single number. It is imperative we know more than a single "R" number. So why do we allow the R-value fairy tale to be perpetuated? I don’t know. I don’t know if anybody knows. It obviously favors fiber insulation. Consider the R-value of an insulation after it has been submersed in water or with a 20 mile per hour wind blowing through it. Obviously the R-value of fiber insulations would go to zero. Under the same conditions, the solid insulations would be largely unaffected. Again R-value numbers are "funny" numbers. They are meaningless unless we know other characteristics.

None of us would ever buy a piece of property if we knew only one dimension. Suppose someone offered a property for $10,000 and told you it was a seven. You would instantly wonder if that meant seven acres, seven square feet, seven miles square, or what. You would want to know where it was -- in a swamp, on a mountain, in downtown Dallas. In other words, one number cannot accurately describe anything. The use of an R-value alone is absolutely ridiculous. Yet we have Code bodies mandating R-values of 20’s or 30’s or 40’s. A fiber insulation having an R-value of 25 placed in a house not properly sealed will allow the wind to blow through it as if there were no insulation. Maybe the R-value is accurate in the tested material in the lab, but it is not even remotely part of the real world. We must start asking for some additional dimensions to our insulation. We need to know its resistance to air penetration, to free water, and to vapor drive. What is the R-value after it is subjected to real world conditions?

The R-value is a fictitious number supposed to indicate a material’s ability to resist heat loss. It is derived by taking the "k" value of a product and dividing it into the number one. The "k" value is the actual measurement of heat transferred through a specific material.

Spray Foam Roofing Benefits

SPF adheres to just about everything so it can be installed over concrete, wood, steel, and most existing roof systems which saves on the expense of roof removal and landfill fees. SPF Roofing installers can spray apply a tapered roof system with the foam which eliminates the need for costly tapered insulation systems. The cants and vertical wall terminations are also spray applied making them an integral part of the roof system and minimizing additional component costs.

Sprayed Polyurethane Foam is applied as a liquid using plural-component spray equipment to fill cracks and crevices. It then expands approximately 30 times its original liquid volume to form a hard, closed cell monolithic roof surface.

The Polyurethane Foam dries within seconds after applied to the roof surface. Its expansion results in a weather tight roofing membrane that is fully adhered to the substrate. Because of polyurethane's lightweight it adds little additional weight to the structure and is often used in remedial applications.

Polyurethane Foam has a history of more than 48 years as a maintainable roofing medium. Polyurethane Foam adds excellent insulation value to the structure and utility bills can reflect the difference.

Once the SPF has been applied to the proper thickness and finish specifications, a protective layer of elastomeric coating or gravel is applied. This protective layer produces a durable weather resistant surface and that can be walked on for normal maintenance.

Durabilty: When most people hear of a "foam" roof, they automatically think of the type of soft foam similar to that used for seat cushions and are concerned that they won't be able to walk on it without causing problems or damaging the roof. Foam roofs are very durable and can handle foot and construction traffic as well as other roofs. They are still susceptible to damage from dropped tools just as any other roof but the damage is more easily seen and can most often be repaired with some simple polyurethane caulking.

 Lifespan: If the coating for an SPF roof is properly maintained, then an SPF roof can last a very long time. Every ten or fifteen years, depending on the type and amount of coating installed, the roof will need to be cleaned, primed, and recoated. If this is done, then a quality SPF roof could last 50 years or longer.

Cost: As with all other roof systems, cost depends on several factors. Some of which include building accessibility, complexity of project, foam thickness, foam coating system, and geographical location. Costs may start at about $2.50 per square foot for a cheap system and go up from there.