Roofing Insulation
Value Engineering - A Win-Win Strategy
06/07/16 Filed in: Value Engineering | Rigid Foam Insulation | ISO | Expanded Polystyrene | Roofing Insulation
Recently, much has been written on the new r-values of polyisocyanurate insulation spurred on by the NRCA Tech Talk. What hasn't been talked about is what does it mean for the consumer? or What opportunities are available for advanced roofing contractor that are willing to educate clients? or How can a Win -Win scenario be used to Win More Jobs?
Experience in the industry has shown that it takes designers and architects several years to catch up and change their project specifications based on new information. This opportunity window allows for roofing contractors to provide a wonderful service and offer "Value Engineering." (Get a copy of - "Value Engineering Tips and Tricks for Roofing")
The recent research has shown that polyisocyanurate (ISO) insulation provides an R-value of 5 R/inch at 40ºF and 4 R/inch at 25ºF. Contrast that to Type VIII Expanded Polystyrene (EPS) that has an r-value of 4.2 R/inch at 40ºF and 4.4 R/inch at 25ºF. Now, take into account that the cost difference between ISO and EPS insulation. ISO Insulation can cost up to 60% more. This really spotlights EPS as the best r-value/inch value. Substituting EPS insulation in for ISO in a value engineering premise is quite simple as the numbers speak volumes. The real trick is how it can be accomplished in an environment that is so "Pro" ISO?
Ultimately, the building owner can win by saving money and yet the contractor can win by proving his professionalism and closing more work - a real Win-Win.
Experience in the industry has shown that it takes designers and architects several years to catch up and change their project specifications based on new information. This opportunity window allows for roofing contractors to provide a wonderful service and offer "Value Engineering." (Get a copy of - "Value Engineering Tips and Tricks for Roofing")
The recent research has shown that polyisocyanurate (ISO) insulation provides an R-value of 5 R/inch at 40ºF and 4 R/inch at 25ºF. Contrast that to Type VIII Expanded Polystyrene (EPS) that has an r-value of 4.2 R/inch at 40ºF and 4.4 R/inch at 25ºF. Now, take into account that the cost difference between ISO and EPS insulation. ISO Insulation can cost up to 60% more. This really spotlights EPS as the best r-value/inch value. Substituting EPS insulation in for ISO in a value engineering premise is quite simple as the numbers speak volumes. The real trick is how it can be accomplished in an environment that is so "Pro" ISO?
Ultimately, the building owner can win by saving money and yet the contractor can win by proving his professionalism and closing more work - a real Win-Win.
The Shrinking R-value of Polyisocyanurate Insulation
What happen to the old days when were told that ISO (Polyisocyanurate) Insulation had an R-Value of 7, 8.3 or 9 per inch. Those days are over! In fact, this last month the “NRCA (National Roofers Contractors Association) has revised its design in-service R-Value recommendation to 5.0 per inch.” (Article)
The real question maybe why? and why another change after last year’s change? The answer is independent testing. According to research conducted by BSC (Building Science Corporation) and others, “the thermal performance of some insulation materials changes as they age. The R-Value of Polyisocyanurate decreases as some of the gasses … diffuse out and are replaced by air.” This is known by several names - Thermal Drift, Gas Replacement Process or Off Gassing.
What the research has shown is that unlike EPS (Expanded Polystyrene) Insulation that increases its R-Value when the temperature decreases, ISO Insulation R-Value actually goes down. Bottom line: In the north, when you need the r-value the most, its not there like we thought.
Solutions
• If you need to use ISO - the BCS Recommendation is to use it in a “hybrid insulation approach” with a cold stable R-Value insulation like EPS.
• Try to substitute out ISO Insulation and use EPS or the New Neopor Plus Insulation.
The real question maybe why? and why another change after last year’s change? The answer is independent testing. According to research conducted by BSC (Building Science Corporation) and others, “the thermal performance of some insulation materials changes as they age. The R-Value of Polyisocyanurate decreases as some of the gasses … diffuse out and are replaced by air.” This is known by several names - Thermal Drift, Gas Replacement Process or Off Gassing.
What the research has shown is that unlike EPS (Expanded Polystyrene) Insulation that increases its R-Value when the temperature decreases, ISO Insulation R-Value actually goes down. Bottom line: In the north, when you need the r-value the most, its not there like we thought.
Solutions
• If you need to use ISO - the BCS Recommendation is to use it in a “hybrid insulation approach” with a cold stable R-Value insulation like EPS.
• Try to substitute out ISO Insulation and use EPS or the New Neopor Plus Insulation.