It is a common misconception that insulation is only to keep warm air in and cold air out of a home. This is simply not true, it is also just as important in reverse. Insulation can help keep your home’s temperature down in the summer which will help lower your utility costs. Your air conditioner won’t have to work as hard in a well insulated home.
Insulating materials contain millions of tiny air pockets that trap heat trying to pass through. The more air pockets per sq inch, the more the material is resistant to heat transfer. This level of resistance is measured in terms of “R-values”. The “R” stands for resistance and the number represents the level of effectiveness of the material. The higher number value the better it will resist heat transfer.
Rigid insulation consists of boards made of polystyrene. It is excellent for insulating roofs, ceilings, foundation basement walls and where you are looking to get a thin layer of insulation with a high R-value. Unlike the other types of insulation, rigid boards are very flammable so it is important to use where you can cover with a fire protection layer such as drywall.
Rigid Insulation Boards usually come as a strange option to the unassuming user. They contain cellulose in their structure, making them an environmentally friendly Insulating solution that helps cut down energy bills. Rigid Insulation boards are designed without the colorful foamy and fluffy elements.
The most commonly used types of rigid foam insulation include the Extruded polystyrene, expanded polystyrene, and Polyisocyanurate boards. For effectiveness, the rigid foam must be sealed on the edges and corners during installation. This can be done using either tape or spray foam or both. In most cases, the Rigid foam needs to be cut for fitting or to facilitate wedging in a process called press fit or friction fit. Alternatively, it can be fitted by gluing using caulk, spray foam, and panel adhesive. The Rigid foam panels come in various sizes and are easy to cut using a saw or knife. However, the most prevalent sizes are 4 ft. by 8 ft. and 2 ft. by 8 ft.
One of the best attributes of the rigid foam is that the panels don’t move or shift out of place. However, rigid foam is more expensive than both cellulose and fiberglass, based on the R-Value, and requires more expertise during installation. Below is an overview of the three types of rigid foam.
* Polyisocyanurate(also known as polyiso) has an R-Value of 6.5-6.8 per inch and comes fitted with a ridged foil. As such, Polyisocyanurate has the highest R-Value compared to the other rigid foam types.
* Expanded Polystyrene panels (EPS) have an R-Value of 3.8 per inch. These panels are the cheapest and are easily damaged.
* Extruded polystyrene(XPS) has an R-Value of 5 per inch. This means that it’s stronger and more expensive than expanded Polystyrene but less expensive than Polyisocyanurate. Extruded polystyrene is waterproofed by nature and the most practical type of foam.
When it comes to choosing, it’s up to the Home Insulators to carry out an Energy Assessment and decide what type of rigid foam best suits home. This process is meant to determine the right R-Value and also evaluate whether or not rigid boards are the right option for you. This will minimize your home’s energy bills.