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These days, there is such an extensive range of roof insulation materials, it is difficult to make a choice. We will list the different products, their possibilities and insulation values for you.
They can be classified into 3 groups: plastic, mineral wool and natural materials.
If you multiply the lambda value by the thickness of the insulating material, you obtain the R-value. This value indicates the insulation value of the total insulation package.
The rule is: the lower this number, the better the insulation value.
Do you only need to insulate a small space? Then it’s best to choose an insulation material with a low lambda value.
| Insulation material | Type | Available as | Lambda value | Info |
|---|---|---|---|---|
|
PUR polyurethane |
plastic |
Foam sheets |
0,023 – 0,028 | Polyurethane is a plastic with excellent insulation value |
|
PIR Polyisocyanurate |
plastic | Sheets | 0,021 – 0,026 | Polyisocyanurate is a plastic with excellent insulation value |
|
EPS Expanded polystyrene |
plastic | Sheets | 0,031 – 0,045 | Expanded polystyrene, also called styrofoam. The material is cheap, but the insulation value is less |
|
XPS Extruded polystyrene |
plastic | Sheets | 0,028 – 0,038 | Extruded polystyrene is also a plastic. It is more expensive than EPS, but has a better insulation value |
| Glass wool | mineral wool |
Roll Blanket Flakes to blow in |
0,031 – 0,044 | Mineral insulation made of silica sand or recycled glass. It is often used for sloping roofs |
| Rock wool | mineral wool |
Roll Blanket Flakes to blow in |
0,031 – 0,044 | Mineral insulation made of volcanic rock that is also popular for sloping roofs |
| Cellular glass | natural product |
Plaques Blocs |
0,04 – 0,05 | Made of glass. Has high pressure resistance |
| Paper flakes | natural product |
Sheets Flakes to blow in |
0,035 – 0,04 | Cellulose is made of recycled paper. |
| Cork | natural product |
Sheets Mats Grains |
0,038 – 0,04 | Limited availability and thus expensive. Mainly used for floor insulation. |
| Hemp | natural product | Blanket sheets | 0,038 – 0,042 | A full-fledged alternative to rock or glass wool. |
| Flax | natural product | Blanket | 0,038 | Comparable to hemp and available in blankets. Its contribution to moisture management is a plus. |
| Sheep's wool | natural product | Mats | 0,035 – 0,04 | Cleaned wool can be processed into insulation mats. |
| Coir | natural product | Blanket | 0,04 | Is mixed with a binder to obtain good stability. Is pest and moisture resistant. |
| Straw | natural product |
Blocks (bales) Sheets |
0,056 | Known from straw bale construction; also available as pressed straw plate. |
| Cotton | natural product |
On a roll Mats |
0,042 | The seed hairs form the basis for insulation. Good thermal and acoustic performance. |
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