Polyisocyanurate foam insulation also commonly known as polyiso is a kind of thermoplastic essentially produced as a foam and is put to use as rigid thermal insulation. It is used in all types of commercial building applications for roof insulation, wall insulation and sheathing purposes. Recently, it has been increasingly employed in residential building projects.
Polyiso is commonly used with a foil facing and contains an r value of 7 to 8 percent thickness.
note: r value is the measurement of heat resistance through an insulation material, which means the greater the r value greater is its resistance ability.
The reflective foil facing renders an excellent insulation material when radiant heat is given out. It also makes it easier to seal it with fine quality tapes.
There are two other types of foam insulation sheets available in the market apart from polyisocyanurate foam insulation. Let’s see how each differs from the other and which is preferred the most in particular type of insulations.
Expanded Polystyrene foam:
It is the cheapest of the lot and least used foam product on the market. It’s r value ranges from 3.6 to 4 per inch in thickness. It is mostly used for insulated concrete forms, and sometimes used on commercial buildings for wall and roof panel insulation that is squeezed between light gauge metal.
Extruded Polystyrene foam:
Commonly known as pink board or blue board is available in variety of thickness and edge profiles. With a r value of 4.5 to 5 inch of thickness, this kind of insulation board is most widely used in residential constructions.
It is lightweight, reasonably priced, easy to use and is ideal for insulating basement walls and under slabs.
It is the most expensive of the lot. These are closed celled foam sheets and contain low conductivity gases in their cells (either HCFC or CFC gases). The reason behind the higher r value of such sheets is due to the thermal resistance of gases in the cells.
This could, in turn, meet some disadvantages such as off gassing of CFC or HCFC gases, and gradual decrease of r value over time as the gases escape.
Applications in various constructions:
In case of roof insulation, polyiso is the only high thermal foam to meet UL 1256 and FM 4450. They are also widely used in walls as their foil faced insulation has the highest r value per inch and u value (unit of measurement of heat transmission through a given thickness such as a wall or a window) of the cavity walls can be achieved with minimum thickness. This lessens the overall footprint of the building as well as lowers construction costs.
Benefits of polyiso sheathing:
If properly specified and installed, polyiso sheathing offers the best value for money for residential construction.
● A residential wall system that has high r value increases energy efficiency at home and considerably minimizes heat loss.
● Reduces air infiltration and exfiltration thus reducing heat loss.
● Reduces the risk of water condensation that increases thermal and structural performance of the wall.
● Hence, by applying polyiso foam sheets, you are rest assured that you have built your home with state of the art energy efficient techniques.
To conclude, make sure you hire the well known construction companies to get the best services. If you are a newbie, you can check out Yitac, a Singapore based company that has been in business for almost 10 years. They have exceptional technical expertise that could serve your engineering needs perfectly.
