Most Common Thermal Insulation Materials

When it comes to insulation there are several options of home insulation types. Ultimately the choice of material will come down to affordability, as the more efficient the material is the more expensive.

There are three main types of thermal insulation materials:

  1. Fiberglass
  2. Cellulose
  3. Spray in polyurethane foam


By far the most commonly used material is fiberglass, which has been used for many years now. The raw material is transformed into a fibre like material in a pumping machine and once it is pumped out it does not settle. This means that it does not lose its effectiveness over time.


Fiberglass is also commonly used in rolls and batts which can be easily installed into attic spaces. It is however a more time consuming process that will cost more than blown in insulation.

Cellulose has become quite popular in recent years due to its environmental friendliness. Made of recycled paper and cardboard, it is applied similar to fiberglass. It is also a more natural product which a lot of people prefer to the alternatives.

Spray in foam is one of the most efficient, but also most expensive home insulation types. Once sprayed into place the foam expands just like spray shaving foam, which ensures that a cavity are is completely filled. Generally it is used to fill in small gaps around opening in buildings, like vents, windows and doors.

In addition to these common materials there are some options for insulating walls where there is no cavity to pump material into. The options here are to either apply internal or external wall insulation, directly to the wall.

For external insulation, the most commonly employed method is to attach tiles made of polystyrene directly on the outside of the building. This is quite a big job, and may be too big a job for most DIY enthusiasts. Bear in mind that if not done properly it can mean that maximum effectiveness is not achieved.

blown in insulationAnother commonly employed home insulation types are foil backed insulation. This is generally used to apply insulation to the interior of a wall. Essentially you get pieces of plasterboard or dry wall, which has a foil back to it that reflects heat. It is a very easy way to add internal insulation when there is no cavity to pump, but it is not one of the cheapest ways.

Today, all materials sold have to be fire resistant insulation. Whether fiberglass, cellulose or polystyrene, the thermal insulation materials have to be treated with fire resistant solutions. But it is always prudent to check the packaging to make sure that it is indeed fire resistant insulation.


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