Procheck FR200

While both of these membranes exceed the requirement for a class B-s3,d0 vapour control layer, FR200 is designed for applications with a low vapour risk, while Procheck A2 has a much higher vapour resistance, making it ideal for situations with a higher vapour load. Procheck A2 additionally has a class A2 fire rating, and a low emissivity surface to gain some thermal benefit from adjacent service cavities.

Yes, as they are membranes used within the warm side of the external wall, and per the 2018 amendments to part B of the building regulations, need to achieve at least B-s3,d0.

Fire resistance is a term used to describe the amount of time that a material will provide resistance to fire, both in terms of heat isolation and physical isolation of spaces. While these membranes are airtight, and therefore would provide some physical separation of spaces, membranes cannot provide significant heat isolation, and are not usually tested for fire resistance. Fire resistance is usually applied to systems, rather than individual products.

Yes, both of these membranes achieve a fire performance of B-s1,d0 or better.

Generally, no, but you are able to use the Procheck A2 with an adjacent cavity for services, and as it has a low emissivity surface, you will gain some thermal performance from that.

They are airtight, as all AVCLs are.

The European standard 13501 defines a series of tests that materials have to undergo to determine their contribution to the spread of flame. These are ranked from F, which is a fail, up to A1, which is non-combustible. A classification of B means that the material performs very well on a single flame source test, and also that it needs to perform pass a single burning item test as well. An A class material needs to pass the same single burning item test, and also needs to release no more than a certain amount of energy in a calorific test. The s and d parts of the classification refer to smoke and flaming droplets respectively, and range from 0-2 for smoke and 1-3 for droplets, with lower numbers representing better performance.

Procheck Adapt is a vapour control layer, but one with a variable vapour resistance. This means that it’s vapour resistance when the climate is warmer and less humid, allows some breathability. With this, materials inside of the VCL are more able to dry out. In all cases, its vapour resistance is greater than 0.06MNs/g, so it can never be classed as a breather membrane. Its function is to allow some breathability from the wall when it is needed, but it is always a vapour control layer

No, Procheck Adapt has the same vapour resistance from either side. It is easiest to apply it by unrolling it onto the wall. It is also transparent, which makes it easier to see where to fix through.

The membrane is fully airtight, achieving an air permeability of 0.00 m³/m²h at 50 pascals. It is also certified as a Passivehouse Airtight component. To ensure airtightness, it is used with Wraptite Tape, which is a vapour permeable, airtight tape.

Yes, if used on solid stone constructions, which many properties are, it allows the masonry some permeability while protecting it from the vapour pressure generated in winter months (when the vapour drive is greatest). This means that the masonry is still able to dry, if the VCL is paired with a vapour permeable insulation. Using a vapour impermeable strategy to insulate solid masonry walls could lead to moisture accumulation, for example if moisture is pushed into the wall by driving precipitation and solar radiation. With no insulation strategy, it would simply pass into the room and be redistributed by natural ventilation. If the insulation is impermeable or if a standard vapour control layer is used, this could cause a build-up of moisture on the internal surface of the masonry. If the insulation is vapour permeable, this moisture would instead permeate through to condense on the back of the VCL. The entire construction would need to offer some permeability to offset this. Procheck Adapt would offer this permeability, while also preventing most of the water vapour from inside from permeating into the wall.

It does. Procheck Adapt serves as a regular vapour control layer, but also allows any moisture (for example, from the construction process, or to reduce damage from leaks) which may have infiltrated the construction to move back into the room.

It is no more difficult than a standard reinforced polythene membrane. It can be cut with a knife or scissors, and is installed using a temporary double sided tape such as our Probond tape, through which fixings appropriate to the substrate hold it in place. Wraptite Tape is then applied over laps and around edges.