Many Irish homeowners renovating old stone-built houses want to make them warmer and more energy-efficient — but airtightness can be a confusing topic. Traditional stone walls built with lime mortar behave very differently from modern block or timber-frame construction, so they need a more sensitive approach.
At Summit Matters Ltd, we specialise in renovating older Irish homes and understand how to balance airtightness, breathability, and building health in stone and lime-mortar structures.
What Airtightness Means for Traditional Stone Homes
Airtightness is about reducing unwanted air leakage — the draughts that sneak through gaps, cracks, and joints in walls, floors, and ceilings. A more airtight home means:
- Better comfort with fewer draughts
- Reduced heat loss and lower energy bills
- Improved control over ventilation and indoor air quality
But airtightness is not about sealing your house completely.
Old stone houses need to breathe, allowing moisture to move naturally through the walls. Blocking that breathability can cause dampness, mould, and long-term structural damage.
The Problem with Modern Airtightness Materials
Many modern airtightness products, such as plastic membranes or cement-based renders, are vapour-closed — meaning they trap moisture. When used on a stone and lime-mortar building, they prevent natural drying and can lead to trapped moisture within the wall.
That’s why improving airtightness in a traditional home must be done using vapour-open, breathable materials that complement lime-based construction.
Breathable Airtightness Solutions for Lime Mortar and Stone Walls
Modern building science now supports what traditional builders always knew — old buildings work best when they can breathe. Thankfully, there are breathable airtightness systems made specifically for historic and stone-built homes.
These include:
- Vapour-open membranes that stop draughts while allowing moisture diffusion.
- Lime or clay plasters that naturally tighten up the building envelope while staying breathable
- Airtight, vapour-open tapes and sealants for windows, doors, and service penetrations
At Summit Matters Ltd, we use these materials to achieve airtightness improvements that respect the building fabric and enhance comfort and energy efficiency.
Practical Airtightness Improvements in Stone Houses
Here’s what airtightness work typically involves in a traditional Irish home renovation:
- Sealing around window and door reveals with breathable airtight tapes
- Applying lime plaster internally to reduce air leakage through walls
- Closing gaps at floor-to-wall and ceiling-to-wall junctions carefully to stop draughts
- Installing controlled ventilation systems (like demand-controlled or heat recovery ventilation) to ensure healthy air exchange
Even small improvements can dramatically improve the comfort and energy performance of an old stone house.
Benefits of Airtightness in Lime Mortar and Stone Buildings
When airtightness is handled properly, you’ll notice:
- Warmer rooms and fewer draughts
- Reduced heating costs
- Better moisture control and healthier air
- Protection for the building structure through proper breathability
A well-balanced airtightness retrofit helps your stone home perform better without losing its original charm or character.
Respecting Heritage While Improving Performance
Every older Irish home tells its own story — and airtightness upgrades should honour that. At Summit Matters Ltd, we create tailored airtightness and insulation plans for each property, ensuring that traditional materials like lime and stone continue to work as intended while meeting modern energy standards.
Thinking about improving the airtightness of your stone-built home?
Talk to Summit Matters Ltd today for expert advice on breathable airtightness systems and lime mortar retrofits in Ireland. We’ll help you make your home warmer, more efficient, and ready for the future — without compromising its heritage.
