Morris County Roofers: Article About Rigid Foam Board Insulation
Moisture and heat intrusion are two of the greatest threats to the structural integrity, performance and longevity of a roofing system. One of the leading causes of unwanted penetration of humidity and outdoor air into an attic is from thermal bridging that takes place through the home's roofing system. A professional inspection performed by experienced Morris County roofers can determine if this issue is taking place and if repairs can be made to correct the problem before serious damage and comfort problems develop.
The best way to detect thermal bridging is when the roof is being replaced. Roofers may start stripping down the roof to its wood sheathing and find that it is damp. Removal of the decking may show that existing fiberglass insulation is damp from condensation or has a layer of frost on it. Either of these situations is a clear sign that air is flowing through rooftop penetrations.
Roofers can stop the phenomenon of thermal bridging by installing a layer of rigid foam board insulation on the roof's exterior side. This kind of insulation has a high R Value and acts as a thermal, air and vapor barrier between the house and the outdoors. When there are no hot or cold spots on the roof, development of condensation or frost is inhibited.
The roofing contractors from Peter W Smith Construction of Morris County NJ would be happy to answer any questions you have about roof replacement or siding repair.
The addition of a layer of this insulation also helps to make the house more energy efficient, less drafty and more comfortable for its residents. The insulation also provides for a greater level of humidity and airflow control.
Property owners and roofing experts can work together to select one of the three types of foam board insulation materials. These include expanded polystyrene, extruded polystyrene and polyisocyanurate. Each of these options has advantages and disadvantages. The expanded polystyrene is most permeable to vapors and has an R Value of 4. It is also the least expensive. Extruded polystyrene is less permeable to vapors and has an R Value of 5 per inch. The best performing type of rigid foam insulation is foil backed polyisocyanurate.
These insulating materials work best when applied along with asphalt roofing felt to work as a water resistant barrier. The seams between pieces of foam must be sealed with an impermeable tape or with flashing strips so that water cannot leak through the tiny gaps. Any other rooftop penetrations, such as chimneys, turbines, furnace flues or plumbing pipes must also be thoroughly flashed and sealed so that water cannot leak through these layers of materials.