High performance joint bandage

Sealing of construction and expansion joints

durajoint flexband is a high performance waterproofing bandage composed of functionalized thermoplastic elastomers for a variety of applications.

The system for installation includes durajoint flexband, durajoint flexband adhesive (FDA compliant), durajoint HDPE strip, durajoint flexband solvent wipe, bond breaking tape and the appropriate sealant for various substrates.

Other auxiliary products where required include durajoint waterstop range and durasheet joint former.


Waterproofing of expansion and construction joints. Applications in critical joint areas with high or frequent movement include:

  • High movement joints (expansion)
  • Construction/contraction joints
  • Joints subject to chemical attack
  • Repair of failed joints
  • Repair/sealing to structural cracks
  • Water retaining structure joint sealing
  • Durable resilient seal
  • Accepts multi-dimensional movement
  • Can be applied to damp substrates (no free standing water)
  • Can be used on a variety of substrates
  • Can be used beneath asphalt
  • Excellent application characteristics
  • Can be used in contact with potable water
  • Resistant to a wide range of chemicals
  • Available in several widths
  • Specification Compliance BS6920
Surface Preparation

The substrate must be structurally sound. Loose or unsound concrete must be removed and rectified where required. Surfaces must be entirely free of oil, grease, paint, corrosion deposits, dust, laitance or other surface deposits. The surface should be prepared by wire brushing, grit blasting, grinding, needle gun or high pressure water blasting to produce a fine exposed aggregate surface. 

Physical Properties
Test  Method  Result 
Burst pressure, max. Internal >5.0 bar
Breaking load longitudinal DIN EN ISO 527-3 14.0 N/mm2
Breaking load lateral DIN EN ISO 527-3 14.0 N/mm2
Extension break longitudinal DIN EN ISO 527-3 1000%
Extension break lateral DIN EN ISO 527-3 1000%
Power absorption at 25% elasticity lateral DIN EN ISO 527-3 5.6 N/mm
Power absorption at 50% elasticity lateral DIN EN ISO 527-3 6.5 N/mm
Resistance to water pressure DIN EN 1928 (method B) >5.0 bar
Resistance to tear longitudinal / lateral DIN EN 12310-2 200 N / 200 N
UV-Resistance, min. DIN EN ISO 4892-3 6500 h
Fire classification DIN EN 4102 B2


Temperature resistance -30 ºC to +90 ºC
Shore A 87 (approx.)
Colour (may vary batch to batch) Grey
1 mm lap bond @ 340 ºC – Peel strength after 24 hours 145 N/25 mm
2 mm lap bond @ 370 ºC – Peel strength after 24 hours 240 N/25 mm
Thickness (mm) *1 and 2
Widths (mm) 150, 200, 250, 300 & 350
*1 mm available on special request
Chemical Resistance
After 7 days submersion at 20ºC (+ = resistant) 
Hydrochloric acid 3% Internal +
Sulphuric acid 35% Internal +
Citric acid 100 g/l Internal +
Lactic acid 5% Internal +
Potassium hydroxide 3%/ 20% Internal + / +
Sodium hypochlorite 0.3g/l Internal +
Salt water (20 g/l sea water salt) Internal +

Priming for the durajoint flexband adhesive is not normally required. If the concrete is friable or very porous a primer may be required. Contact a.b.e.®  for a site inspection and recommendations. See durajoint flexband adhesive product data sheet. 

Membrane Preparation

Cut the durajoint flexband membrane to the required length, then clean the faces to be bonded by wiping with durajoint flexband solvent wipe. Allow the surfaces to dry before bedding it into the durajoint flexband adhesive. If left for more than 8 hours, the membrane edges must be cleaned again and allowed to dry.

Prepare durajoint flexband lap joints in advance by allowing a minimum of 100 mm overlap. The joints can only be made by using a hot air gun. To ensure intimate contact between bonded laps, place the durajoint flexband on a clean flat laminated timber board and apply pressure to the joint as it is being formed using a Leister roller to ensure maximum bond. All lap joints are to be carried out prior to installation.

For welding lap joints the following equipment is required:

Leister Triac AT – Hot air heat gun Nozzle: 40 mm Roller: 40 mm wide 30 mm diameter

1 mm durajoint flexband temperature setting of 340 °C

2 mm durajoint flexband temperature setting of 370 °C

Mixing – Epoxy Adhesive

Refer to the durajoint flexband adhesive product datasheet. 


Mask the area where the durajoint flexband adhesive is to be placed i.e. 25 mm on the concrete surface and extended 50 mm from the edge of the durajoint flexband membrane inwards.

Where support below the durajoint flexband is required, position the durajoint HDPE strip to centrally straddle the expansion joint.

A minimum thickness of 1 mm durajoint flexband adhesive applied to the concrete surface is required. After spreading the durajoint flexband adhesive, remove the innermost masking tape from both sides of the joint. Immediately place the durajoint flexband membrane, and using a hard roller, firmly roll the bandage to allow extrusion of the durajoint flexband adhesive beyond the edges of the membrane. Apply a second layer of durajoint flexband adhesive on top of the first layer to give a total durajoint flexband adhesive thickness of 2 mm and finish using a steel trowel. Remove the centrally placed masking tape from the dura.joint flexband membrane.

Remove the outer masking tape and featheredge the durajoint flexband adhesive by using a paint brush to chamfer any sharp edges/corners that may cut the membrane. Concrete surface profile and irregularities will influence the consumption rate of the durajoint flexband adhesive. See method statement for process.

  • Do not apply to concrete substrates that are less than 28 days old
  • Do not apply to wet substrates (having free standing water)
  • Do not apply in rain or wet conditions or at temperatures below 10 °C
  • Do not fully immerse the joint system until full cure is achieved (7 days at 25 °C, lower temperatures require a longer curing period)
  • Do not expose the joint to traffic without the use of a suitable cover plate or protection

durajoint flexband as per roll length excluding overlaps durajoint flexband adhesive: Approximate theoretical quantities for estimation: 2 mm thick/m2 = 2 litres of product.



Tools may be cleaned with abe® super brush cleaner immediately after use before the dura.joint flexband adhesive has had time to cure, otherwise mechanical means will be required. 

Model Specification

dura.joint flexband high performance waterproofing bandage system composed of functionalized thermoplastic elastomers.

For sealing of joints as per manufacturers requirements.

  • dura.joint flexband is supplied in 20 metre rolls, see table for available widths.
  • dura.joint HDPE strips: 3 mm thick, 50 & 75mm wide x 3m long
  • dura.joint flexband adhesive: 2 litre kits
  • dura.joint flexband solvent wipe: 5 litre container
  • abe® super brush cleaner: 5 litre container
Handling & Storage

durajoint flexband Maximum 12 months when stored below 25 °C under shade in a dry environment, protect against sunlight. If package has been opened apply the material within 2 months. 

Health & Safety

Product safety information required for safe use is not included. Before handling, read product and safety data sheets and container labels for safe use, physical and health hazard information. The safety data sheet is available from your local a.b.e.® sales representative.

Important Notice

This data sheet is issued as a guide to the use of the product(s) concerned. Whilst a.b.e.® endeavours to ensure that any advice, recommendation, specification or information is accurate and correct, the company cannot accept any liability for application – because a.b.e.® has no direct or continuous control over where and how a.b.e.® products are applied.

Further Information

Where other products are to be used in conjunction with this material, the relevant technical data sheets should be consulted to determine total

a.b.e.® has a wealth of technical and practical experience built up over the years in the company’s pursuit of excellence in building and construction


Download datasheet for illustrations of typical expansion joint detail for durajoint flexband & PVC centrebulb waterstop