Hello!
I suspect this might be technically challenging, but I still want to hear about the possibilities and others' experiences.
Currently, there is a substandard vapor barrier in the exterior walls, and the plan is to fix this when the rooms are being renovated. The house will also be additionally insulated from the outside at a later stage.
To do it by the book, you should have an installation layer for all the electricals to avoid puncturing the plastic. Doing so will also give you a deeper window niche, which is nice, of course. Crossed studs to eliminate thermal bridges, etc. The advantages are many.
Some walls are not a problem at all, while other walls become more difficult since there are radiators on them. The radiator pipes come up from the concrete slab about 45mm from the existing wallboard, and they are, of course, millimeter-fitted to go straight into the radiators underneath (single-pipe system, TA-RVE-15).
In any case, I have to dismantle the radiators to install the plastic, so that job falls on me anyway.
Is it just a matter of forgetting about it and trying to seal around the boxes the best you can? How would you have done it?
I suspect this might be technically challenging, but I still want to hear about the possibilities and others' experiences.
Currently, there is a substandard vapor barrier in the exterior walls, and the plan is to fix this when the rooms are being renovated. The house will also be additionally insulated from the outside at a later stage.
To do it by the book, you should have an installation layer for all the electricals to avoid puncturing the plastic. Doing so will also give you a deeper window niche, which is nice, of course. Crossed studs to eliminate thermal bridges, etc. The advantages are many.
Some walls are not a problem at all, while other walls become more difficult since there are radiators on them. The radiator pipes come up from the concrete slab about 45mm from the existing wallboard, and they are, of course, millimeter-fitted to go straight into the radiators underneath (single-pipe system, TA-RVE-15).
In any case, I have to dismantle the radiators to install the plastic, so that job falls on me anyway.
Is it just a matter of forgetting about it and trying to seal around the boxes the best you can? How would you have done it?
The house is from '72. There's some form of plastic on the backside of the existing drywall. I don't know if that was common practice or if the plastic is simply worn out, but from what I've seen, it seems that the drywall came with a thin plastic on the back. Then they just put them up and cut out for all the sockets, etc. Not airtight at all.Jonatan79 said:
The ceiling against the attic has been placed on top of the ceiling joists (to gain ceiling height, I assume) and then a plastic, which is absolutely not taped, has been laid out, with insulation placed on top.
The plan is to open up to the ridge. Then that problem is solved.
Edit: We have mechanical exhaust ventilation.
Sure, I hear what you're saying but the conditions will change somewhat when we add insulation to the house. We currently have 95mm of insulation and the plan is to add the same amount again. However, we will keep it under 200mm as many suggest that the threshold is there.
Good question! (from TS)
But, difficult to answer.
It's always tricky with existing houses as the detailed execution of the whole house is unknown. Additionally, repairs/renovations and possible extensions often increase the uncertainty even more. It's almost impossible to know without carefully tearing down the entire structure...
Waterproofing becomes more important the thicker the insulation the house has. This is because the thicker the wall, the more difficult/longer it takes to ventilate away any intruding moisture.
In the attic, additional insulation lowers the temperature, thereby increasing RH, which raises the risk of mold growth. Leakage of indoor air brings both heat and moisture to the attic. Theory and practice quite unanimously point in the same direction as far as I know - minimize moisture addition to reduce the risk of moisture problems.
If the attic is not going to be additionally insulated, and there are no problems after >50 years, there's no reason to change anything.
I would disregard the installation layer and try to seal as well as possible around the electrical installations.
But, difficult to answer.
It's always tricky with existing houses as the detailed execution of the whole house is unknown. Additionally, repairs/renovations and possible extensions often increase the uncertainty even more. It's almost impossible to know without carefully tearing down the entire structure...
Waterproofing becomes more important the thicker the insulation the house has. This is because the thicker the wall, the more difficult/longer it takes to ventilate away any intruding moisture.
In the attic, additional insulation lowers the temperature, thereby increasing RH, which raises the risk of mold growth. Leakage of indoor air brings both heat and moisture to the attic. Theory and practice quite unanimously point in the same direction as far as I know - minimize moisture addition to reduce the risk of moisture problems.
If the attic is not going to be additionally insulated, and there are no problems after >50 years, there's no reason to change anything.
I would disregard the installation layer and try to seal as well as possible around the electrical installations.
Jag har tänkt så det knakar och jag tror att det hela löser sig rätt bra ändå.Oldboy said:
Bra fråga! (från TS)
Men, svårt att svara på.
Det är alltid besvärligt med befintliga hus då detaljutförande i hela huset är okänt. Dessutom brukar reparationer/renoveringar och ev tillbyggnationer göra osäkerheten än större. I stort sett omöjligt att veta utan att riva hela kåken försiktigt...
Tätskikt blir viktigare ju tjockare isolering
huset har. Det beror på att ju tjockare vägg desto svårare/längre tid tar det att ventilera bort ev inträngande fukt.
På vinden gör tilläggsisolering att temperaturen sjunker, och därmed ökar RH, vilket ger ökad risk för mögeltillväxt. Läckage av inomhusluft tillför vinden både värme och fukt. Teori och praktik pekar tämligen entydigt åt samma håll såvitt jag vet - minimera fukttillskott för att minska risken för fuktproblem.
Ska vinden inte tilläggsisoleras, och det inte finns några problem efter >50 år så finns det ingen anledning att ändra något.
Jag hade struntat i installationsskikt och försökt täta så gott det går runt elinstallationer.
De verkar ha tänkt lite när det bygde huset för det finns inga elinstallationer längst med långsidorna som i princip är helgödslade med fönster och element. Man har förhållit sig till innerväggar förutom i tre rum längst med gavlarna där det finns ett par eluttag i yttervägg men inga fönster att ta hänsyn till.
Det skulle inte märkas om jag gör installationsväggar i dessa rum på dessa specifika väggar förutom att rumsytan minskar med 45mm då förståss. Där skulle jag kunna få ordentligt tätt för de få elinstallationer som faktiskt finns i yttervägg.