From £135.39 + VAT per 50m x 1.5m roll

Paper Vapour control and airtightness membrane – Sisalex 303

Sisalex 303 paper vapour control and airtightness membrane is:-

  • a tear resistant paper membrane, with an Sd value of 5m, that regulates the moisture flow through walls, roofs and floors.
  • suitable for blown cellulose or wood fibre insulation
  • perfect for use with Ampacoll Easy paper airtightness tapes.
  • plastic free, reducing waste and pollution.

Product overview

Where is it used?

On the inside of timber/metal frames/dry lining, on the inside of roof structures or on the top side of floors.

How is it used?

  • Sisalex 303 vapour control membrane can be bonded, using Ampacoll DT double sided tape, to the underside of rafters or the inside of timber studs prior to being boarded over or counter battened.
  • If using on the inside surface of wood fibre insulation boards, apply Ampacoll Primax primer and Ampacoll DT double sided tape to the surface at regular intervals to allow the membrane to be bonded to the surface.
  • Once each row of membrane is in place simply tape the joints with Ampacoll Easy airtightness tape.
  • All joints should overlap by at least 100mm and the perimeter should be sealed prior to counter battening or being over boarded with plaster board.
  • Once the joints are taped it forms an air tight, moisture regulating layer.
  • Any penetrations, such as joists, pipes, cables or ducts should be sealed with Ampacoll BK 535 penetration sealing tape.

How much will you need?

Each roll of Sisalex 303 vapour control membrane is 50m long and 1.5m wide. It covers an area of 70m2 accounting for overlaps.

Frequently asked questions

Do I need to tape the joints?

Yes, you should always tape the laps, usually with the Ampacoll Easy or Ampacoll INT airtightness tapes. This ensures the air tightness of the membrane and that it functions correctly to reduce moisture flow through the walls from the interior.

What are its properties?

  • The Sd value of the membrane is 5m which makes it ideal when wood fibre insulation has been used on the outside as a sheathing board as it maintains the correct vapour diffusion gradient across the wall.
  • Being made of paper, it can be composted or recycled.

Pricing & shipping

This product is on a 1.5m long roll and will be sent by courier, costing around £20 + VAT

Roll length [m]Roll width [m]Roll Area [m²]Membrane weight [g/m²]Roll weight [kg]Sd value [m]Single roll cost [£]3+ rolls [each]

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