Independent Acoustics and Noise Control Expertise Custom Audio Designs Ltd 

Acoustic tapeExpanding foam sealing tapefoam sealing tapeAcoustic foam sealing tapeAcoustic Expanding foam sealing tape

Acoustic and weatherproof expanding foam sealing tape

Expanding Foam Sealing Tapes

Expanding Foam Acoustic Joint Sealing Tapes
A self adhesive high quality, high density, open cell foam sealing tape which has been impregnated to a high level with acrylics and FR additives. The product is CFC and HCFC free and contains no Chloride compounds.

When the Xpandafoam foam tape is compressed the cells close thus providing for a variety of sealing applications as detailed below:

  • 20% compression - Dust Seal
  • 50% compression - Thermal
  • 65% compression - Draught / Acoustic
  • 75% compression - Acoustic / Protected weather seal - Not directly exposed to water or UV.
  • 80% compression - Acoustic / Weather seal to 600Pa - Will resist water spray up to 600Pa differential to EN86.

Xpandafoam tape is supplied pre-compressed for ease of application. All coils have a reinforced self adhesive backing. When the rolls are opened the tape expands to about 5 times its compressed thickness. The product is designed to accommodate movement in joints and seals against uneven surfaces. For full acoustic and weather sealing applications you do not want the tape to expand fully. For example EXP5/12 comes 5mm thick before opened and should not be allowed to expand further than 12mm for best results.

The elasticity and flexibility is such that it will seal gaps between uneven surfaces such as brickwork and concrete and maintains its elasticity and responds continually to expansion and contraction cycles without any joint failure. Tests to monitor the life expectancy reveal no significant deterioration over 20 years in use.

Xpandafoam is also ideal as as a weatherstripping material to fill expansion joints or for the filling of voids. It will create a draught, dust, wind and driving rain seal and has a guaranteed life spac of 20 years. Approved to DIN 4102 and DIN 18542 the tape is compatible with most other building materials.

We recommend using Xpandafoam when installing our acoustic doors to give the maximum acoustic benefits. The 5mm gap between the structure and the frame must be sufficiently sealed to prevent noise leakage around the door. Using this product along with our fire rated flexible acoustic sealant will maintain the acoustic and fire integrity of the door assembly.

Xpandafoam can also be used around the perimeter of acoustic floors, acoustic ceilings. Its also ideal for sealing gaps between pipes and services where they penetrate through a wall or floor.

1. Storage and Surface Preparation
Tape should be stored in a warm dry interior location. Ideal application temperature is approximately 24°C. Expansion will be faster at higher temperatures and slower at lower temperatures. Full expansion normally takes about 24hrs from when the material is first opened but when re-compressed it will re-expand within minutes. For faster expansion in cold conditions keep the material warm before use and, if desired, apply heat from a hair dryer to installed material to accelerate expansion.

Joint faces should be dry and cleaned of dirt, oil and grease etc. There should be sufficient depth to receive the full width of the tape.

IMPORTANT: Reels should be stored flat and kept compact. Should material expand in package it can still be used. Unroll the material, allow it to expand, then recompress it between surfaces to be sealed.

2. Opening Reels
Only open rolls that will be used immediately.

3. Square Off Ends
Start and finish ends must be cut square. For easier cutting spray the knife or scissors with a mist of water.

4. Peel Off Liner
A suitable length or section should be cut to fit the opening. The material only expands in one direction i.e. its thickness not its width. For acoustic purposes we recommend that it not be allowed to expand more than 35% of its fully expanded thickness so its important to check the gap size before using (or ordering) the material. For larger gaps two layers can be stuck one ontop of the other. Remove release liner to expose the adhesive backing face of the tape.

5. Adhere To Surfaces
Position the tape and press to secure. If needed, cut and fit smaller filler pieces of tape to fill panel or corrugation voids.

6. Join Lengths with Miters
To form a continuous strip overlap tapes and miter with a moist knife at a 45° angle. Pinch the mitered faces together.

Please Note: This product is for use as an acoustic expansion gap seal it is not designed to be an Intumescent Expansion Gap product. If you are looking for a fire rated acoustic intumescent product please click here:

Other Applications

  • Structural concrete joints and pre-cast panel joints
  • Sealing and finishing of roofing and cladding panels
  • Sealing of door, window frames and rooflights
  • Sealing partitions and interior or exterior panels
  • Sealing of pre-cast concrete guttering
  • Sealing of non-pressurised water or sewer pipes
  • Sealing of roofs, panels, window frames and doorframes in vans, campers, [portable and modular buildings or mobile offices
  • Sealing of plastic corrugated plastic panels, metal roofing and wall sheets
  • Sealing eaves
  • Anti corrosion joints for metal to metal fixtures
  • Perimeter sealing of conservatory systems between brickwork and plate
  • Sealant backer and expansion joints
  • Wood constuction - log homes and cabins

Tape TypeFull ExpansionCoil Length
EXP1/4expands to 9mm13m
EXP4/9expands to 21mm8m
EXP5/12expands to 28mm5.6m
EXP6/15expands to 36mm4.3m
EXP9/20expands to 47mm3.3m
EXP11/25expands to 60mm2.6m
EXP18/24expands to 95mm3.3m
EXP24/42expands to 120mm2.6m
We can cut to any width, 25mm is generally a standard width but user to specify

FoamPolyurethane with impregnation
AdhesiveAcrylic dispersion
ThicknessPre-compressed rolls, one side self adhesive
length of roll: 2-12m depending on thickness
thickness: 10-150mm (decompressed)
widths: 10-1000mm
Tensile strength DIN 53 571At least 100kPa
Tensile elongation DIN 53 571At least 200%
Compressive strength at a compression of +40°C DIN 53 577ca. 3,4 kPa (+/- 15%)
Behaviour under fire DIN 4102-1B1 (P-NDS04-284)
Temperature resistance-30°C until +100°C + 130°C for short time
Permeability of joints DIN EN 1026 (DIN EN 42)coefficient of joint permeability a<0,1 m³/.hm (daPa)n
Water tightness under heavy rain wind force: 11/height of building: 100m DIN EN 1027 (DIN EN 86)>600 Pa / stress group B1 (wind force: 11/height of building: 100m)
Sound absorptionR'ST.w:48dB
Weathering resistance< 10 years
Thermal conductivity0.07 W/mK

All information contained in these details is given in good faith but without warranty.
Custom Audio Designs reserves the right to alter the specifications of any product without notice.
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