Vent Cards

A breathable vent card is required by Irish building regulations.

“B.5.2.1R2(a) Insulation between and below rafters, 50 mm ventilated cavity between insulation and breathable membrane” 2019 Part L Building Regs.

We recommend that you install a breathable vent card approximately 50mm from the roofing felt to allow cold air to pass freely and allow the timber in your roof to breathe. This also has the advantage that the spray foam has not breached the integrity of your roof, and if there are any issues with your tiles or felt down the line, you can repair it without affecting the insulation.


Spray foam insulation is a totally inert product and does not disintegrate or deteriorate over time. It does not need to be topped up regularly like fibre glass type products.

Since it is an airtight product it not only prevents warm air escaping your house, but it also prevents cold air getting in. It also has the advantage of preventing allergens such as mold or pollen entering your home.

Spray foam is applied between the rafters rather than on the floor of your attic, and so it will help prevent your water pipes freezing in cold weather.

SEAI Grant

Spray Foam is suitable for the SEAI insulation grant. In order to qualify you must apply for the grant before starting any insulation works.

All homeowners, including landlords, whose homes were built and occupied before 2006 can apply.

You will ask your contractor to give you a quotation and complete the application on the SEAI website.

Once you have been approved you can engage your spray foam contractor, pay them in full, and then claim the grant directly from the SEAI. You must complete the works and submit the paperwork within 8 months from the date of the grant offer. You can find the expiry date in your offer letter.

For more information check out the SEAI website:

NSAI Certificate

Red Letter Supplies sell NSAI certified open and closed cell foam. The National Safety Authority of Ireland have exhaustively tested our foam to ensure that it is safe for use in Irish properties. They have awarded it an Irish Agrément Certificate. Please download our NSAI certificate here: