Wall Insulation

U value for walls can be no more than 0.27W/m2K on both new buildings and extensions to existing buildings. This requirement is set out in Part L of the Building Regulations.

The most common form of insulation used for floor insulation in Ireland is Polyiso. We stock Polyiso wall insulation, and at Glynns we stock this from two manufacturers, Xtratherm and Quinntherm. This ensures our prices always remain competitive and service is never compromised.

For cavity wall constructions we stock 60mm Tongued and Grooved Polyiso, which is the most commonly used wall insulation will allow you to achieve between 0.22 and .028 W/m2K depending on the Lamba of the concrete blocks used.

In timber frame constructions we recommend 140mm Rockwool Flexi Slab.140mm Rockwool Flexi Slab is specific designed for this application. Used with Standard Breathable Membrane and one layer of slab you will achieve 0.27 W/m2k. By using Tyvek Reflex Breathable Membrane and one layer of slab you will achieve 0.24 W/m2k.

Remember the lower the U Value the better!

With existing houses you have three options to insulate external walls:

1. Cavity Wall Insulation

You can have the cavity pumped with insulation which is a service we don't provide but we would be happy to recommend a reputable company. There is a SEI Grant of €400 available to do this work. Go to our SEI Grants section in the Renewable Energy Centre Section for more info. You can also insulate both externally (€4,000 SEI Grant available) and internally (€2,500 SEI Grant available).


2. External insulation

This is growing in popularity and is a specialized job which is only done by specific insulation contractors. We can provide you with details if required. Click here for a noval way to insulate your home or building externally.


3. Internal insulation

This can consist of battens or metal frames attached to the inside of the external walls and 50mm Rockwool Flexi Slab packed between the battens or metal frames. Then Insulated plasterboard is fixed in place. This is usually 38mm but both 50mm and 60mm are available also.


Email us today with your measurements and we will recommend the most cost effective option for you.