Below FAQ are some common questions of our clients that you may find helpful. If you have other questions, please email us at info@membranes.build
GENERAL
Yes, there are options for retrofitting all of our membrane systems onto existing buildings. Please talk to one of our instal experts to discuss your specific needs.
We do all types of buildings, including Passive House. All buildings need a weather resistive barrier (WRB) (sometimes called the weather tight layer), and some, including passive house, also need intelligent air barriers (IAB). We stock WRB and IAB membranes and accessories.
High-performance buildings utilize smart membranes for their weather resistive barrier (WRB) along with quality insulation, windows, and orientation.
AIR TIGHTNESS
An airtight membrane creates an airtight layer around the building structure. Creating an airtight building, along with appropriate insulation, helps reduce the need for heating and cooling.
A intentional airtight uninterrupted layer in the thermal fabric of your building, ideally in our opinion located on the warm side of the construction. Intelligent airtightness barriers increase the drying potential of the assembly but these barriers can also be rigid air barriers (RAB).
Airtightness barriers quite simply remove unintended gaps in the building envelope that would allow air to pass in or out uncontrolled. Essentially they create a draught-free building which controls the heated or cooled air from leaking out of the building.
A high performance building will have higher levels of occupant comfort with reduced heating and cooling demand. These buildings could meet or exceed what is required by the Passive House Institute but the difference is that a Certified Passive House (or Passivhaus) is a verification process starting at design stage using their Passive House Planning Package (PHPP) both running in parallel to make sure the design meets the stringent energy and health standards and the verification continues right through to the completion stages of the construction phase, which is all submitted for assessment before being awarded the prestigious recognition.
We do provide window perimeter low expansion foam insulation but our core products are weather & air resistant barriers designed to protect the insulation in your building from wind washing ect. which largely devalues the insulation properties.
WEATHER TIGHTNESS
A WRB is designed to prevent water from reaching building components that could be damaged by moisture. It should be assumed that cladding (wall or roof) installations aren’t truly waterproof, and that some water will find its way through or around the cladding (at least once in a while). Without a WRB, structural framing and other parts of the wall assembly would be much more susceptible to damage.
Every building needs a weather resistive barrier (WRB), so you should always use one if you’re constructing a building, not so much if you’re building a car.
A WRB is designed to prevent water from reaching building components that could be damaged by moisture. It should be assumed that cladding (wall or roof) installations aren’t truly waterproof, and that some water will find its way through or around the cladding (at least once in a while). Without a WRB, structural framing and other parts of the wall assembly would be much more susceptible to damage.
VAPOUR BARRIER
A vapour barrier stops moisture from passing through it. It’s typically used on the inner side of the insulation and often acts as the air tightness layer as well.
When storing food for freshness like chips in a foil chip packet…:) vapour barriers are sometimes used to prevent building assemblies from getting wet but they often prevent them from also drying out which can be very dangerous. Vapour barriers are sometimes specified in extremely hot and humid or extremely cold arctic locations where vapour drive is one directional for most of the time but verification that the system works for the climate is critically important through hygrothermal analysis software like WUFI.
Most climate zones in Australia benefit from vapour permeable weather resistive barriers (WRB) and vapour barriers are known to be problematic in those zones.
As referenced under AS:4200.1 Pliable Building Membranes & Underlays Clause 5.3.4 (Vapour Control Classification) Table 4. A vapour barrier membrane is classified as meeting the criteria of a Class 1 or 2 Vapour Control Membrane.
VAPOUR PERMEABLE MEMBRANES
Vapour permeable membranes allow moisture in its’ vapour state to pass from one side of the membrane to the other, usually from the insulation layer to outside the building envelope. This helps to dry your insulation layer if any moisture does get in.
SARKING
Sarking is a common term that was used for foil bonded pliable membranes.
Roof sarking is a term used for foil bonded pliable membranes which are not recommended in some climate zones. Our team can assist you with the correctly specified membrane for your building location.