INSULATION FOR CAVITY WALLS (FULLY FILLED)


Insulation For Cavity Walls (Fully Filled)Buildings with traditional cavity wall construction have great potential to have their thermal performance improved by filling the cavity with an insulating product. In some cases where the cavity already contains an insulant but it has failed due to settling or moisture ingress, it may be possible to remove the failed product and replace it with a more suitable alternative.

A PUR or PIR foam system can injected into the cavity via holes in the outer leaf producing insulation with excellent adhesive and structural properties. The product bonds the inner and outer leaves together thus eliminating the problem of wall tie failure.

The table below compare the improvements that can be achieved by installing various cavity wall insulating products at a cavity thickness of 50mm in the conventional cavity wall. The lower the U-value the better the insulation performance.

Insulating product (Thermal conductivity W/m.K) U-value (W/m².K)
   
PUR (0.025) 0.40
Expanded polystyrene beads (0.037) 0.55
Mineral fibre (0.039) 0.57
Urea formaldehyde (0.040) 0.58
No insulation 1.50

Benefits of PUR/PIR insulation for cavity walls (fully filled):

  • Provides the best thermal performance of all practical full cavity insulants;
  • Resistant to all climate exposure conditions;
  • Ensures continuity of insulation and does not settle or leave part of the cavity uninsulated;
  • Gives a useful life in excess of 50 years with a constant thermal performance;
  • Eliminates the risk of water penetration;
  • Is recommended by the Environment Agency as a measure to reduce flood damage to walls;
  • Is resistant to moisture ingress;
  • Provides wall stabilisation, especially useful where wall ties are failing;
  • Have a British Standard specification and code of practice for their installation (BS 7456 and BS 7457);
  • Are installed with no disruption to the occupants or other ongoing activities;
  • Are BBA approved for use anywhere in the country (unlike other types of insulant whose use is geographically restricted);
  • Are non-fibrous and do not emit harmful emissions;
  • Do not support the growth of fungi.

For further information please contact:
Elastogran UK
Isothane Limited

Insulation For Cavity Walls (Fully Filled)