Masonry Wall External Insulation
- External wall finish to manufacturers recommendations.
- External wall insulation to manufacturers recommendations.
Select insulation thickness and thermal conductivity in the calculator below. - 215mm (min.) block solid wall.
Select block thermal conductivity in the calculator below. - 12.5mm (min.) plasterboard on adhesive dabs.
General construction notes
Where firebreaks are required due to compliance with Building Regulations, their
inclusion would locally change the thermal bridging Ψ values modelled here.
Appropriate weathertight bead/seal between window frame and insulation. Compressed sealing tape, weatherseal bead or alternative to manufacturers recommendations.
For ground floor junctions, rigid insulation below DPC and ground level to provide
thermal resistance equal to, or better than, main wall insulation.
Minimum 15mm overlap of window frame/cill and external wall insulation. If frame size does not permit the required overlap, then packing may be required at
the head with head heights suitably adjusted.
Outer face of blockwork and window frame to align.
ψ Value Calculator
To calculate overall U-value and ψ values follow the following steps:
