In previous articles, we have discussed flat roof insulation, inverted roof insulation and wall and floor insulation – various applications testifying to the versatility of our insulation solutions. Yet there is even more, because SOPREMA is also your go-to partner for loft insulation. Whether you opt for a cold loft or a warm loft, we have the type of insulation that meets your requirements. We also offer all the service and support you need to bring your project to completion with the highest level of quality. In what follows, we share some crucial pointers, especially when it comes to converting a loft into a habitable space.
Insulating A Cold Loft
One of the easiest and quickest ways to improve the energy efficiency rating of a residential building is by creating a cold loft. Without proper insulation immediately above the ceiling of the top storey, a lot of the indoor heat will escape through the roof. By adding insulation between the joists or on top of the attic floor, the warmth in the living space below is retained. The loft then becomes a cold space – hence the name – and can be perfectly used for storage purposes.
A flexible insulation product is your easiest option here: unroll the insulation material, lay it between the joists or on top of the attic floor, and use scissors to cut it to fit. The more insulation, the better the performance, so feel free to add multiple layers. A minimum depth of 300 millimetres of insulation is recommended. And why not opt for natural insulation? In the case of a cold loft, there is no need to achieve high compressive strength, so you can safely select a lighter-density material such as PAVAFLEX or PAVATEXTIL. The latter panel is made from recycled cotton and has excellent thermal and acoustic insulation properties. Its flexibility and light weight make it easy to cut and quick to install. Moreover, PAVATEXTIL naturally regulates the moisture balance, and retains its thickness and insulating properties year after year.
Warm Loft Insulation
1. Thermal Performance
Converting a loft into a habitable space means you’re creating a warm loft. Here, your first option is taking off the roof covering and insulating the attic from the outside, but that is obviously no small task. Moreover, this method may cause complications in terms of planning, because it changes the height of the building. The preferable way to go about it, then, is insulating immediately under the roof. You can either place insulation between the rafters or below the rafters. There are various factors to take into account when deciding between these two options and selecting the best insulation material.
The first criterion to consider is the depth of the rafters. If the rafters are shallow, insulating below them might be the smartest move – unless you opt for PIR insulation, which offers excellent thermal insulation even in boards with limited thickness. The second criterion is the aesthetic finish you want to achieve. If you want to leave the rafters exposed, you have no choice but to place the insulation material between them. Do you prefer a plastered finish? Then you can, for instance, use wood fibre insulation and cover it with plasterboard.
In any case, when insulating between the rafters, a flexible insulation product is preferable to rigid insulation boards – especially when the rafters are not perfectly straight. After all, a blanket insulation product can be easily squeezed between the rafters, reducing the risk of air gaps.
2. Overheating Protection
While thermal performance is obviously important in regard to loft insulation, your insulation material might need to do more than prevent heat from escaping. Since temperatures in a loft space can rise up to 50° or even 60°C on sunny days, overheating protection also becomes an issue. An insulation product with more mass, such as PAVATEX, is particularly effective at buffering heat, as it ‘soaks up’ the heat from the sun – which conventional insulation is unable to do.
More specifically, PAVATEX has an ideal decrement delay of twelve hours. Because it takes twelve hours for the highest temperature to pass through the roof fabric, the midday temperature does not reach the indoors until night-time. The heat from the outside is stored within the PAVATEX wood fibre insulation, making for pleasant day time temperatures, and slowly released to the outside during the night.
Advice On Loft Insulation
As there are so many criteria to take into account when selecting the right insulation material for your loft insulation project, expert advice might come in handy. Rest assured: our team is happy to help.