hello!
Very, very slowly renovating a 1920s home (lime) hopefully to a high energy-efficient standard.
Facade just been repointed with lime. Also planning to install wood fibre insulation and lime plaster inside.
All the information I look at mentions solid walls when going the 'breathable' route. But my external walls have a very narrow cavity. Would this make a difference to how I insulate/how thick I can insulate without shifting the dew point too far?
Future plans include heat recovery ventilation and air to air heat pump. Repointing and fixing roof, drainage and window leaks means very little water ingress. In combination with good air circulation, heating and lime, I don't expect the same problems as the neighbours who've sealed everything up with polyurethane and gypsum and are having serious mould issues. Just a little worried that their sound insulation on the party walls pushes more water vapour to my side, so perhaps I'm going a little overboard. Better safe than sorry.
So for high airtightness, breathability and thermal efficiency what's the best way to insulate the internal side of the external walls (with a 3 - 4 cm cavity)? Air gap or no air gap? Smart vapour control membrane or none? Vapour permeable airtight membrane (on walls) necessary when adding a 2cm layer of lime to the walls, or just seal off the ceilings to keep the heat from the air to air heat pump in the allocated spaces?
Thank you!
Sarah.
Very, very slowly renovating a 1920s home (lime) hopefully to a high energy-efficient standard.
Facade just been repointed with lime. Also planning to install wood fibre insulation and lime plaster inside.
All the information I look at mentions solid walls when going the 'breathable' route. But my external walls have a very narrow cavity. Would this make a difference to how I insulate/how thick I can insulate without shifting the dew point too far?
Future plans include heat recovery ventilation and air to air heat pump. Repointing and fixing roof, drainage and window leaks means very little water ingress. In combination with good air circulation, heating and lime, I don't expect the same problems as the neighbours who've sealed everything up with polyurethane and gypsum and are having serious mould issues. Just a little worried that their sound insulation on the party walls pushes more water vapour to my side, so perhaps I'm going a little overboard. Better safe than sorry.
So for high airtightness, breathability and thermal efficiency what's the best way to insulate the internal side of the external walls (with a 3 - 4 cm cavity)? Air gap or no air gap? Smart vapour control membrane or none? Vapour permeable airtight membrane (on walls) necessary when adding a 2cm layer of lime to the walls, or just seal off the ceilings to keep the heat from the air to air heat pump in the allocated spaces?
Thank you!
Sarah.