Aluminum and composite foils in roof insulation
Functional aluminum and composite foils in roof insulation
When renovating and/or building new roofs, insulation is always installed. The basic aim here is to create an airtight and windtight seal. In general, diffusion-open foils that act as so-called diffusion-tight vapor barriers are suitable for this purpose.
Vapor barrier
Vapor retarders are components with a water vapor diffusion resistance. This prevents the diffusion of moisture from the warm air in the interior into the thermal insulation of the building. This is particularly important in the colder months of the year. The warm indoor air can absorb more moisture than the significantly colder outdoor air. This leads to an increased water vapor partial pressure in the warmer indoor air. The actual function of the vapor barrier is to prevent warm, humid air from penetrating the roof structure and forming condensation.
The water vapor diffusion resistance has a defined bounce value (sd value) of greater than 0.50 m. The choice of vapor barrier depends on the overall structure of the roof construction.
Laminated films
Sound insulation, thermal insulation and cold insulation can also be realized with composite foils. Aluminum composite foils are used for roof insulation. This is a plastic film (polyester film or polypropylene or polyethylene film) that is processed with aluminum foil on one or both sides. Its main purpose is to ensure that radiant heat is not lost. Insulation materials made of glass fibers, for example, cannot stop or reduce these radiation losses to the same extent.
Functional insulation
Such composite foils are produced by extrusion. Aluminum foil, which is used for roof insulation, is the most versatile material in insulation. It can be bonded to the thermal insulation panels used and acts as a vapor barrier. Above all, this prevents mold from settling. It also reduces the risk of fire.
Aluminum composite foils are also used for thermal insulation, cold insulation, sound insulation and fire protection. This is possible due to its versatile properties. Above all, it has a high tear resistance and is harmless to health.
The special feature of using aluminum composite films is that they are partially perforated. This allows air to circulate and prevents condensation from forming, which can lead to mold growth.
High energy efficiency
At the same time, insulation boards are also processed, which are processed directly with the composite foil. They consist of an insulating core made of rigid polyurethane foam and the vapor-diffusion sealed aluminum composite foil, which is processed here in several layers.
This form of insulation has low thermal conductivity and therefore also thermal resistance. This enables very high energy savings to be made and at the same time good architectural designs can be realized. The laminated aluminium foil optimizes the vapour barrier and the edges of the boards in particular consist of a clamp-press connection. They are processed in a tongue and groove plug-in system. This creates a windproof and at the same time thermal bridge-free surface for the roof insulation.
