From £16.95 + VAT per roll

Penetration sealing tape – Ampacoll BK 535 – 50mm

Ampacoll BK 535 penetration sealing tape is:-

  • a single sided, incredibly elastic adhesive tape with a split backing which allows simple, weathertight sealing of all penetrations.
  • suitable for internal and external use on all types of timber boards and membranes, removing the need for pre-formed grommets or gaskets.
  • suitable for all types of masonry and in areas of high humidity.
  • suitable for winter application down to 0 degrees C.

Product overview

Where is it used?

  • Ampacoll BK 535 penetration sealing tape can be used internally and externally, on walls, roofs or floors.
  • It is used to permanently seal around rafter, purlin, duct, vent, pipe or cable penetrations through vapour control, moisture barrier or breathable membranes.
  • Also suitable for air tightness sealing of timber sole plates to masonry plinths/slabs in timber frame construction.

How is it used?

  • Surfaces should be clean, dry and free of dust before the tape is applied. Porous, dirty or friable surfaces, such as masonry or wood fibre boards, must be primed with Ampacoll Primax Primer prior to application.
  • Ampacoll BK 535 penetration sealing tape bonds instantly to the surface so it is important to apply carefully.
  • Cut the tape to the required length and then remove one of the backing strips.
  • Apply the tape slowly and firmly to the object penetrating the membrane first. Once the tape covers the entire perimeter of the object with a 50mm overlap, remove the second backing strip.
  • Slowly and firmly press down and stretch the tape against the membrane or board surface, ensuring a good bond.

How much will you need?

  • Obviously you need to measure the perimeter of the object you’re sealing around and the best way to do that is by simply wrapping the tape around it. However, to get the right seal you do need to add 50mm or so for an overlap.
  • The rolls are 25m long

Frequently asked questions

Can I use this tape in winter?

Yes, you can use it in temperatures all the way down to zero.

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

Material in action

Play Video

This video, which is in German, shows very clearly how simple it is to seal around simple penetrations such as pipes and ducts and also how elastic the tape is.

If you have to seal an airtightness membrane or vapour control layer around a load of rafter feet or around the studs in a wall, this is the tape for you.

Technical details

Pricing & shipping

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

Roll width [mm]Roll length [m]Number of rolls per boxAmount of tape per box [m]Type of backingSingle roll costFull box roll cost
50mm25410050:50 split£86.22£77.60
50mm5126050:50 split£18.83£16.95

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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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