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Toplite GTI - high thermal insulation


Toplite GTI - Aircrete Block 

Toplite GTI blocks provide high insulation properties making them particularly suitable for external wall applications where low U-values are required. They may also be used in situations where it is important to construct walls with low self-weight.


Toplite GTI working dimensions

Face dimensions (mm) are 440mm long x (various widths) x 215mm high.


Block widths and weights

Block width (mm) 100 115 125 140 150 200 215
Unit weight (kg) 4.5 5.2 5.6 6.3 6.7 9.0 9.6
Laid weight (kg/m²) 56 64 70 79 84 113 121


Unit and laid weights, which are given for design purposes, are approximate and calculated based on the specified dry density with a 3% moisture content by weight added to provide equilibrium weights.

Toplite GTI applications

  • Inner leaf of cavity walls
  • Outer leaf of cavity walls, where cladding is to be used
  • Solid external walls, clad or rendered
  • Foundation walls - inner leaf

Toplite GTI environmental performance

Toplite GTI is manufactured under an ISO 14001 compliant Environmental Management System that is independently certified by BSI. Summary green guide ratings applicable to Toplite aircrete blocks can be found in the BRE Green Guide to Specification www.thegreenguide.org.uk.

Greater thicknesses are available in Toplite Foundation.

Toplite GTI specification

  • Mean compressive strength: 2.9N/mm²
  • Thermal conductivity: 0.11W/mK
  • Gross dry density: 460kg/m³
  • Reaction to fire: Class A1

Toplite GTI is manufactured to comply with EN 771-4 and conforms to Category 1 manufacturing control as specified in BS 5628-1.

Find out more about Toplite GTI


Blocks Orders & Helpline

0845 606 2468

Technical Services

0870 242 1489

email the technical team 

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