From £30.52 + VAT per 25m roll

Window & Membrane edging tape – Ampacoll Fenax

Ampacoll Fenax window & membrane sealing tape is:-

  • a 75 – 100mm wide, plasterable, UV stable, highly adhesive tape.
  • for sealing windows and membrane edges to masonry and timber surfaces, without needing a primer.
  • available in split-back and double-sided forms to enable sealing in all sorts of situations.
  • also suitable for taping cut joins in wood fibre sarking boards without a primer.
  • suitable for winter application down to -5 degrees C.
  • resistant to exposure for up to 12 months.

Product overview

Where is it used?

  • Ampacoll Fenax window & membrane sealing tape can be used internally or externally to seal around windows and the edges of membranes or other building components to masonry or timber substrates, without requiring a primer.
  • Ampacoll Fenax window & membrane sealing tape can also be used for taping the cut joints in our wood fibre sarking boards, also without needing a primer.
  • The tape is suitable for roofs and walls but should not be used at or below ground level.

How is it used?

  • Surfaces should be clean, dry and free of dust before the tape is applied. Brush well to remove any dust and dirt.
  • For taping membrane edges, fold about 40 mm of the membrane over the flank wall, the adhesive line on the Ampack membrane serves as orientation.
  • Using the Ampacoll Fenax 40/60, remove the liner of the narrower, 40 mm-wide strip and stick the tape onto the membrane. The flank wall serves as a solid base for pressing the tape firmly on to the membrane or use the Ampack pressure roller to do this.
  • Create a pressure relief loop by sliding the Ampacoll Fenax 40/60 tape and the membrane to be connected upwards by 15mm or so (see data sheets for clarification). This is important and ensures that no tension is put on the tape should the building move.
  • Remove the liner of the 60 mm-wide strip of Ampacoll Fenax and stick the tape onto the flank wall by firmly pressing it against the wall. If the surface is not even, make sure that the tape follows the profile of the wall.
  • This tape can then be plastered over to make the junction permanently airtight.
  • On wood fibre sarking boards ensure there are no loose fibres on the surface of the board and that it is dry.
  • The Ampacoll Fenax 40/60 tape can be applied at equal widths to both surfaces and should be firmly rollered to ensure maximum bond strength.
  • For taping around windows using the Ampacoll Fenax 12/88, 12/63 or DS 30/70, see the Ampack window installation guide.

How much will you need?

Each roll of Ampacoll Fenax tape is 100mm wide and 25m long.

Frequently asked questions

Can I use this tape in winter?

Yes, you can use it in temperatures all the way down to -5°C.

Will it stick in wet conditions?

No, the surfaces must be clean and dry. If they are dirty, use the Ampacoll Primax Primer.

Product videos

Rendered installations:-

Play Video

For a guide on how to use Ampacoll Fenax DS 30/70 to ensure new window installations are weathertight and airtight, please see the videos here


Clad installations:-

Play Video

Pricing & shipping

This product comes in a small box and so will be sent by courier, costing around £13 + VAT.

TapeRoll width [mm]Roll length [m]Number of rolls per boxAmount of tape per box [m]backing slit widths [mm]Single roll costRoll cost in full boxes
Fenax 40/60100mm25410060-40£33.91£30.52
Fenax 12/88100mm25410012 – 88£48.34£43.51
Fenax 12/6375mm25615012 – 63£38.24£34.42
Fenax 30/70 DS100mm25410030 one side – 70 the other, double sided£57.72£51.95

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