Drylined Walls Insulation – Design Guidance

To minimise thermal bridging at window and door reveals insulation should be installed along the face of the reveal and butted to the window frame (figure 22). If space constraints preclude the use of battens, the plasterboard should be fixed to the wall through the Ballytherm insulation boards.

Thermal bridges can also occur where interior walls meet external walls; one solution is to extend the insulation for at least a metre along both faces of the internal wall, although to avoid projections in the wall it may be appropriate to continue the insulation to an internal corner (figure 23).

In intermediate floors, insulation should be placed between the inner surface of wall and the joist, which runs next to it (figure 24).

Walls must be prepared for installation: projections such as skirting boards, architraves and copings should be removed to give a smooth surface, uneven walls may need to be rendered; service fixtures such as sockets and switches should be removed to be re-fitted later.

Existing finishes with a high vapour resistance, such as vinyl wallpaper or gloss paint should be removed to avoid problems with condensation.

The cavities formed by the battens may
be used for service runs to reduce
penetrations through the insulation where existing services are taken
through the insulation the penetrations
should be sealed. Lightweight fittings 
may be fixed to the plasterboard, but
fixings for heavier fittings should be
taken back to the masonry.

Additional battens should be used to support heavy horizontal items.

a insulation fitted along face of reveal b insulation extended along face of internal wall insulation between inner face of wall and joist

Further Advice & Information

For more information about Ballytherm products, technical advice, or guidance on the suitability of our products for your project, contact us at + 353 (0)49 95 27000,, email us at info@ballytherm.ie or use our contact form.

Floor Insulation