Why Foam Building Science Benefits & Case Studies FAQ About Us Contact Us Home
thermacote systemsspf applied by certified technicianSPF applied by certified technician.

correct wall cavityCorrect wall cavity.

correct roof deckCorrect roof deck.

What is SPF?
How does foam insulation work and why?
Open-cell VS. closed-cell?

What is SPF?

SPF is an acronym for Spray Polyurethane Foam.  SPF is a microcellular plastic (micro-cells or bubbles in a rigid or semi-rigid plastic) made from two chemical components that when mixed together create a chemical reaction and form SPF.  The History Channel recently documented spray polyurethane foam as one of its Modern Marvels and calls polyurethane foam the “secret weapon in the war on energy consumption” as well as the “super-insulator of insulation products”.  Polyurethane Foam was developed and first used during World War times in the 1930’s – 1940’s in the aviation industry because of its strength but lightweight character.  Later, polyurethane foam was used as an insulation product on ice boxes and freezers beginning in the 1950’s.  Application contractors began to spray foam as early as the 1970’s, which has led to the Spray Polyurethane Foam industry that is growing at a market share rate of 40%+ since 2004.  Today, polyurethane foam is used to insulate most appliances and coolers, and is used in furniture, cars, adhesives, and in construction and recreation.

The chemicals used to create polyurethane foam contain flame retardants used to reduce the surface burning characteristics to a Class I building material with a flame spread index below 25 and a smoke developed rating below 450 as tested by the American Society for Testing and Materials (ASTM E84).  New formulations of polyurethane foam do not include asbestos, formaldehyde, fibers, CFCs, HCFCs, or other ozone depleting chemicals.

How does foam insulation work and why?

First consider these facts provided by the U.S. Department of Energy (DoE):
The U.S. DoE estimates that each year over $13 billion worth of energy is lost through holes, and cracks in residential buildings alone.  The U.S. DoE has also conducted tests that conclude that air infiltration and convection looping (the rise and fall of warm and cold air within the wall or attic) wastes up to 40% of every home heating and cooling dollar by increasing the load required by the homes heating and air conditioning unit.  Air infiltration and convection looping reduce the R-value which causes the heating and cooling unit to work harder to make up for lost R-value.  The average U.S. home uses 50% of its energy consumption on heating and cooling, therefore up to 40 cents of each of those dollars are lost due to air infiltration.

Now consider why SPF eliminates these problems:
SPF is applied as a liquid that expands and cures (hardens) and which bonds to the building structure in any shape or form.  Because SPF is applied as a liquid, it instantly works its way into any crack, crevice, or joint to seal and create a continuous air barrier.  SPF can also be a vapor retarder around sill plates, headers, truss ends, base boards, electrical outlets, piping and around windows and doors.  By sealing these problem areas, SPF can eliminate air and moisture infiltration and air movement in the wall cavity (called convection looping), which protects the living environment from uncontrolled air movement and damaging moisture.  SPF meets all national building code requirements and international residential codes and approvals.

Conventional forms of insulation simply cannot prevent air and moisture infiltration and air movement the way foam insulation can.  Once the house is built, there are many hidden and unwanted cracks, holes, and gaps where air and moisture move freely through a building.  These uncontrolled movements of air and moisture reduce the laboratory R-value for these conventional forms of insulation.  The savings on the installation of less expensive conventional insulations come at the cost of long term performance and payback.

Conversely, SPF simultaneously insulates and air seals to create the tightest possible envelope around the living environment for superior energy efficiency providing the highest return on investment while producing a more comfortable living or work environment.

Spray Polyurethane Foam carries the Energy Star Seal approved by the U.S. Department of Energy and the product is a major component to obtaining the requirements for the tax credits and deductions provided by the Energy Policy Act of 2005.

SPF is one step toward Energy Efficient Mortgages now offered by most home financing lenders.  Mortgage companies know that by significantly reducing your energy bills, you can afford more home and a larger mortgage for the same money out of your pocket.

SPF makes your home more marketable and increases the market value by proven lower utility bills, controlled humidity, quieter living conditions, and superior indoor air quality.

Open-cell VS. closed-cell?

Open-cell or semi-rigid foam is also called .5 lb (“half pound”) foam.  This means that the foam weighs approximately one half pound per cubic foot and speaks to the density of the foam.  Open-cell SPF is a low density, non-structural insulation system that affords critical air sealing that can result in better air quality and increased comfort to building occupants. Open-cell foam is a water blown foam that has minute cracks in the walls of the micro-cells of the foam.  This is where the name “open-cell” is derived.  When the foam is sprayed at approximately 140 degrees, the exothermic reaction creates the small cracks in the cells.  Because the cells are open, this gives open-cell foam a semi-rigid or spongy quality.  Open-cell foam is an air barrier, typically limited to internal applications, and typically costs less than closed cell foam.

The Technical Datasheet of Bayseal OC (open-cell), states the following Physical Properties:
R Value (aged) ASTM C-518:
R-3.9 at 1 inch
R-13 at 3.5 inches
R-19 at 5.5 inches

Sound Transmission Coefficient ASTM E-90: 51 (STC)
Noise Reduction Coefficient ASTM C-423: .7 (NRC)
Fungi Resistance ASTM G-21: Zero rating
Surface Burning Characteristics ASTM Method E84 (UL 723): Class 1

Closed-cell or rigid foam is also called 2.0 lb (“two pound”) foam.  The foam weighs approximately 2 pounds per cubic foot and is significantly denser than half pound foam.  Closed-cell SPF is a medium density structural insulation system that yields a high R-value and minimizes air and moisture infiltration and increases structural integrity; all qualities that add to the durability of a structure.  Closed-cell foam uses a blowing agent called 245fa that remains in the closed cells.  Unlike open-cell foam, the cells do not crack.  This is where the name “closed-cell” is derived.  The blowing agent remains in the cell to hold the cell structure and give closed cell the rigid characteristic.  Closed-cell foam is an air barrier, vapor retarder, and can be used for internal and external applications.

The Technical Datasheet of Bayseal CC (closed-cell), states the following Physical Properties:
R Value (aged) ASTM C-518:
R-6.9 at 1 inch
R-13 at 1.9 inches
R-19 at 2.75 inches
R-24 at 3.5 inches
R-37.8 at 5.5 inches
R-54.3 at 7.9 inches

Sound Transmission Coefficient ASTM E-90-85/E413: 43 (STC)
Noise Reduction Coefficient ASTM C-423: .2 (NRC)
Fungi Resistance ASTM G-21: Zero rating

Surface Burning Characteristics ASTM Method E84 (UL 723): Class 1

Top of Page