Arbothane 1245


One part polyurethane sealant which cures, on exposure to moisture vapour, to form a firm, flexible rubber.

Can be used for joints in sea walls, and in trafficked floor joints which require a fast cure.

Non-biodegradable and abrasion resistant.

Not recommended for joints in lightweight cladding, very heavily trafficked areas, or use against natural stone.

Health and safety:

Contains isocyanates; adequate ventilation is required; avoid contact with eyes and skin.

General information

Specification data - Polyurethane (PUR) construction joint sealants

Product Reference

Arbothane 1245



Arbo Cleaner No.17

Arbo Cleaner No.16

Arbothane porous primer

Arbothane non-porous primer

Standard product features

Specification Compliances:

  • BS EN ISO 11600 -F-20HM.

Technical data:

  • Typical Shore A hardness: 40.
  • Application temperature: +5°C to +40°C.
  • Service temperature: -40°C to +80°C.
  • Skinning time at 23°C and 50% relative humidity: 90 minutes.
  • Cure time at 23°C and 50% relative humidity: 4 mm after 48 hours.
  • Chemical resistance: Resistant to most dilute acids and hydrocarbon solvents.
  • UV resistance: Minimal discoloration.
  • Service life: 15+ years.

Movement accommodation:

  • Butt joints (movement in tension and compression): 20%.
  • Lap joints (movement in shear): 40%.


  • Concrete grey.

Joint sizes:


  • Minimum: 6 mm.
  • Maximum: 25 mm (single application); 35 mm (multiple applications).

Design joint width:

  • Butt joint: Expected movement x 6.
  • Lap joint: Expected movement x 2.5.


  • Minimum: 10 mm on porous substrates, 6 mm on non-porous substrates.
  • Maximum: 18 mm.

Width:Depth ratio (within the above minimum/ maximum restrictions):

  • Butt joints: 2:1.
  • Lap or floor joints: 1:1.