Spray Foam Insulations are not all created equal!

Product Description
Walltite is a medium density (1.9 lb/ ft3), closed cell, spray applied polyurethane foam that performs the functions of insulation and air barrier.  Walltite can be applied to the exterior side of sheathing or onto the interior of sheathing, between studs.  The system may include a transition membrane applied over moving joints and at junctions between different assemblies and at penetrations. 

Low Density Polyurethane Foam Insulation has an open cell structure and a density of 0.5 lb/ ft.  It is applied between studs onto the interior side of sheathing. 

Thermal Performance
The measure of an insulations thermal performance is currently “R Value”.  To retain the R-value for any insulation it is critical that it be installed to eliminate convective air currents.  Insulation must be installed in intimate contact with the substrate and with no gaps.  A spray-applied product is inherently more capable of making intimate contact with the substrate versus board or batt insulation.

Walltite has a long term thermal resistance (LTTR) as follows; 1 inch= R6.3, 2inches = R 13.1, 3 inches = R20.4, 4 inches = R29.2.  CCMC suggests a conservative value of R6 per inch.
Walltite adheres tenaciously to all typical construction substrates and readily conforms to irregular surfaces such as stud cavities.  Convective air movement is eliminated and the maximum R-value is retained.

Low Density Polyurethane Foam Insulation has an R value of 3.6/inch.  To obtain R-20 5.5 inches will be needed prompting the need for a 2X6 framing system. 

With Walltite a 2X4 inch framing system can be used resulting in more floor space as well as shorter brick ties, doorjambs and other related materials.

Air Barrier Performance
Walltite has been tested, and is listed by CCMC, as an insulation, air barrier material and air barrier system.  The CCMC listing # 12877 shows that 38 mm of Walltite has an extremely low air leakage rate of 0.000418 L/(s.m2) at 75Pa ∆P. 
Walltite has undergone extensive testing as an air barrier system as described in the CCMC report 12932-R.  This testing is a larger scale and was designed to replicate all of the conditions found in real world construction.  The air leakage rate of Walltite (25.4mm thickness) through this rigorous testing is 0.0054 L/(s.m2) at 75Pa ∆P or less than 1/10 of the most stringent code requirement.

Low Density Polyurethane Foam Insulation is listed by CCMC only as insulation and typically not as an air barrier.  A major manufacturer reports an air barrier material test result for a 75 mm thickness of 0.0080 L/(s.m2) at 75Pa ∆P.  This is over 20 times the leakage for a sample twice the thickness of Walltite! 

Exposure
Walltite can be installed and left exposed to weather for up to 6 months without any significant reduction in performance.  The closed cell structure of Walltite makes it resistant to water absorption and the high compressive strength (32 psi) enables it to withstand mechanical abrasion and impact.  The CCMC 12932-R testing requires a high level of exposure to heat, wet dry cycling and lateral wind loading prior to being tested for air leakage.

Low Density Polyurethane Foam Insulation is not intended for exposure to exterior conditions, moisture or any mechanical abrasion.

Moisture Absorption

Insulation performs best if dry.  The moisture absorption of Walltite is <4% after being immersed for 48 hours. 

BASF Enertite is listed CCMC 13055-R is a Type 2 Low Density Foam and has an absorption rate of <5%.  Most manufacturers of low density foam report absorption between 40 to 70% by volume or greater.  Foam with high moisture content will have a reduced R value.  A foam with 40 % absorption by volume has the potential of absorbing over 200 lbs of water per 100 sq ft wall @ 6 inches thick.

Installation
Spray applied insulations are typically faster to install than batt or board insulations.  Walltite is simply sprayed to the appropriate thickness and left until covered. 

Low Density Polyurethane Foam Insulation is sprayed between studs and is allowed to rise past the face of the stud.  It is then trimmed flush to the stud using a saw or other tool.  The waste is then collected and disposed of. 

Quality Assurance
Walltite is installed by licensed and experienced installers trained by BASF and inspected by a third party agency.  When Walltite is specified as an air barrier system it is mandatory that at least one third party inspection be made at the contractor’s expense.  The entire inspection and training system is audited by CCMC and is part of the CCMC approvals for Walltite.

The installation of low density foam products is not as controlled or regulated making them vulnerable to poor application.  Third party inspection must be requested by the architect and is often at the owner’s expense.

Adhesion
High adhesion to substrates reduces the possibility of convective air movement and improves resistance to wind loads.

Walltite has been tested for adhesion to all typical construction substrates.  Adhesion is typically 15 to 35 psi and is much higher than other materials.  The adhesion of Walltite to the substrate and to the transition membrane is part of the routine testing required on air barrier system projects.  The high adhesive properties and high compressive strength of Walltite enable it to increase the racking strength of stud walls dramatically.

Adhesion of Low Density Polyurethane Foam Insulation is minimal as it has low tensile strength.  No racking strength increase is reported by the manufacturers.

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