Don’t Leave Your Customers Out In the Cold
Understanding insulation alternatives in garage door applications
By Aaron Latimer
No longer relegated to backyards, garages are playing a more prominent role in overall home design. Given that more homes today are constructed with bedrooms and additional living space above the garage, it is critical for builders to consider garage insulation value and its relationship to the overall energy efficiency of the home.
With garage doors accounting for up to 40 percent of the front of a home, there is significant potential for heat loss and energy inefficiency, which ultimately shows up in a homeowner’s utility bills. In fact, heating and cooling is responsible for the largest part of those utility bills, accounting for 50 to 70 percent of energy used in a home. With the costs of heating and cooling a home on the rise, understanding the insulation alternatives in garage door applications and the payback to consumers can be beneficial to your door dealer operation.
A basic physical law of nature is that heat travels from warmer areas to cooler areas. If the outdoor air temperature is 10 degrees and you are maintaining the air temperature within your house at 70 degrees, heat has a strong tendency to flow out of the house. It does so in three basic ways:
- Conduction—the transfer of heat through a solid material.
- Convection—the flow of heat through a fluid substance, such as air or water.
- Radiation—the transfer of heat energy via invisible rays.
The best way to reduce heat transfer is through thermal insulation. The effectiveness of thermal insulation in cutting down conductive heat loss and its flow through solid materials like walls, ceilings and floors is measured by its level of “thermal resistance,” otherwise known in the industry as R-value. In short, the higher the R-value, the more effective the insulation will be.
Polystyrene and polyurethane are two primary types of insulation available in the manufacturing of garage doors. Like any form of insulation, both these materials differ in their composition and have varying degrees of effectiveness in reducing heat loss. Let’s take a closer look at both types.
This substance comes in two forms: expanded and extruded. Both have similar characteristics when properly used.
Expanded polystyrene is composed of melded tiny beads of material similar to coffee cups. With an R-value ranging from R 3.6 to R 4.4 per inch of thickness, expanded polystyrene varies according to compressive strength, but is designed for long-term durability. Its plastic composition will not corrode, rot or facilitate any buildup of moisture, mold or mildew. Polystyrene is also resistant to most chemicals except petroleum-based solvents which can destroy the material.
Extruded polystyrene starts out as solid granules of resin. When fed into an extruder, the granules melt and are mixed with other additives until the substance reaches a useable liquid state. A blowing agent turns the liquid into foam, which is ready for application.
The final product is a closed-cell structure that resembles a landscape of evenly formed bubbles, yet is smooth with almost no gaps in its structure.
Extruded polystyrene has an R-value of R 5 per inch of thickness. It acts as a vapor retardant, although air permeating through the material can compromise its R-value. The excellent moisture resistance of extruded polystyrene has been confirmed repeatedly and consistently in laboratory tests under field use conditions. Both expanded and extruded are found to be stable to 165 degrees Fahrenheit.
One of the most effective garage insulation materials around today is polyurethane foams which have some of the highest R-value ratings on the market, ranging from R 5.8 to R 8 per inch of thickness.
The closed-cell structure of polyurethane insulation helps the foam to resist moisture penetration. Polyurethane materials are lightweight, which allow the use of thinner material to achieve higher R-Value as compared to polystyrene. The lightweight characteristic is why builders use polyurethane insulation for construction projects involving prefabricated panels, from warehouses to office structures. In garage doors, polyurethane is used only in fully cured panels which have no isocyanate or polyol properties, meaning the product is inert. Polyurethane possesses dimensional stability and offers one of the highest strength-to-weight ratios of any insulation product.
Polyurethane foam does not settle, sag or droop and does not structurally deteriorate or decompose. Polyurethane materials are resistant to oil-based waterproofing products, insecticides and fertilizers. They are found to be stable to 250 degrees Fahrenheit.
Polystyrene and polyurethane insulation make a significant contribution to the environment by providing improved energy efficiency. Both polystyrene and polyurethane have the capacity to use environmentally friendly blowing agents such as pentane, which is CFC or HCFC-free, resulting in zero ozone depletion and zero global warming effects.
One advantage of polystyrene is that it can be recycled. It can be crushed or ground into small particles and added back to the process. Polyurethane boasts an overall stronger rating in the ecological footprint, which is a method of analyzing the effects of several factors pertaining to a product such as energy consumption, emissions and health effect potential. As the North American marketplace becomes more familiar with “green” products and consumers increase the demand for such products, garage door manufacturers will undoubtedly be looking at options to meet the changing needs of the marketplace.
By virtue of its dense properties, higher R-value, and moisture and heat resistance, polyurethane insulation boasts a number of advantages over polystyrene. However the bottom line for the door dealer is reminding customers of the importance of the investment in an insulated garage door. The long-term returns for customers in saved energy dollars, comfort, health and safety for their homes is certain to create a win-win for everyone in the industry.
Aaron Latimer is the national marketing manager for Steel-Craft Door Products Ltd., a Canadian-based manufacturer of commercial and residential overhead doors. The company has been in business since 1948. To learn more about Steel-Craft, visit www.steel-craft.ca.