From £174.35 + VAT per 50m x 1.5m roll

Highly breathable airtightness membrane – Ampatex LDA 0.02 – 1.5m x 50m

Ampatex LDA 0.02 highly breathable membrane is:-

  • a triple layer, tear proof, highly vapour permeable underlay for creating airtightness layers  in renovation projects over existing structures.
  • highly vapour permeable but airtight at the same time.
  • used as part of our internal wall insulation strategies.

Product overview

Where is it used?

For use directly on to the outside of timber walls. loft and roof structures to create an airtightness layer within insulation layers.

How is it used?

  • Ampatex LDA 0.02 highly breathable membrane is usually laid on top of the first layer of insulation to go between studs/rafters/joists.
  • All joints should overlap by at least 100mm and any vertical joints should be taped with Ampacoll INT airtightness tape prior to the next layer of insulation being applied.
  • Use Ampacoll DT double sided tape to hold the membrane down to timber surfaces prior to taping joints and overlaying more insulation.
  • Any penetrations of rafters, vents, ducts or pipes should be sealed with Ampacoll BK 535 penetration sealing tape.

How much will you need?

Each roll of Ampatex LDA 0.02 highly breathable membrane is 50m long and 1.5m wide. It covers an area of 70m2 including overlaps.

Frequently asked questions

Do I need to tape the joints?

Yes, you should always tape the laps, usually with the Ampacoll INT tape. This ensures the air-tightness of the layer, reduces heat loss from wind penetration and prevents building damage from warm moist air condensing within the structure.

How long can I leave it exposed?

This membrane is not very UV stable and should not be exposed to sunlight for more than 1 week. Beyond this the sun can begin to degrade the strength and weather resistance of the membrane.

Technical details

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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If you can’t seem to find what you need on our website or you have large quantities of materials to purchase please contact us for a chat and we’ll offer you a more bespoke solution.

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