Choosing the right air and vapour control layer for a building project is critical to ensure full functionality of the insulation and its optimum performance, thus resulting in greater energy efficiency and more comfortable internal climate.
What is the right Sd-value ?
The higher the Sd value of the air and vapour control layer, the higher the protection of the insulation against a warm and humid indoor climate. However, a higher Sd value also means a less dryout out capability. Humidity can accumulate in a building during construction in many ways and can be difficult to control, whether this be through wet trades, poor detailing or other sources. This can then result in condensation and mould growth.
AVCLs with a variable sd-value offer excellent protection against condensation risk and potential damage
During the winter the sd-value of the membrane increases as the relative humidity within the building interior increases, thus reducing moisture transfer towards the insulation when va- pour control is needed most. The sd-value decreases as the relative humidity drops during the summer months, allowing the construction to dry out towards the interior.
High mechanical strength helps to make the product easier to install
A mechanical strong membrane has less risk of being damaged during installation through tearing or puncturing. DuPont AVCL’s products, based on DuPont nonwoven material technology, are very robust compared to Polyethylene, spunbond polypropylene or polyester based products.
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