Can I just replace the sawdust with insulation?

[nybyggarn3]

In all houses, human activity generates moisture. Cooking, washing dishes, doing laundry, showering, and even breathing releases moist air!
This warm, moist air rises, and if there isn't a vapor barrier in the ceiling joist, the moisture will reach the attic.
It's just pure physics.

If it then gets too cold in the attic, the air won't be able to hold as much moisture, causing the moisture to condense on the cold surfaces, usually the roof decking.
Again, pure physics that's hardly arguable.

There are different ways to handle the issue:
- keep it warm in the attic
- install a vapor barrier
- ventilate the moist air out before it can cause damage (the problem then is what to replace the air with; sometimes the outdoor air is just as moist).

Nicely explained. Installing a vapor barrier in a house from 1920 should probably be considered a major intervention. Keeping it warm in the attic is the solution the whole thing is based on. Unfortunately, it's quite expensive these days.

 

[Aunty]

Now we're talking about a house from 1920 and not 2020. The house is built entirely without a vapor barrier. Therefore, all moist air will rise up to the attic. The thin insulation makes it relatively warm in the attic, which is an advantage. Spraying on insulation in modern amounts will lower the temperature. The risk then is that there will be problems.

Yeah, but that's what I'm saying.

If there's a risk, then just manage it; there are plenty of ways to address this. Also, we don't know anything about the conditions in this house, maybe there's no moisture ingress.

 

[nybyggarn3]

är ju precis det jag säger, tror man sig att det är ett problem så får man ju hantera det. finns massvis med bra sätt att hantera det på beroende på risk.

No, that is not correct. If you pile on insulation and it starts to mold in the attic, it can become a problem. Being well-informed about the problem is a good start.

 

[Aunty]

Well explained. Installing a vapor barrier in a house from 1920 should probably be considered a major intervention. Keeping the attic warm is the solution that it all relies on. Unfortunately, quite expensive nowadays.

but a security guard in the attic can't be considered particularly expensive if it's warmth in the attic you're after?

 

[b8q]

Moreover, we know nothing about the conditions in this house, maybe there is no moisture supply

You mean no one lives there? I think we can almost rule that out.

 

[nybyggarn3]

but a security guard in the attic can't be considered particularly expensive if it's specifically warmth in the attic you're after?

What does one of those do?

 

[Aunty]

You mean that no one lives there? I think we can almost rule that out.

maybe there's a steam barrier, maybe there's negative pressure, maybe there's an ftx system, maybe there's an unventilated attic, maybe the roof has been additionally insulated.

one must know the conditions to know what measures might need to be done.
no one is saying there's no risk for damage, what I'm saying is that it can be managed.

however, if you want to add insulation, you shouldn't use kutterspån but other materials, kutterspån is bad for several reasons and should never be used. (there are special cases where you can use it)

 

[nybyggarn3]

maybe there is a vapor barrier, maybe there is negative pressure, maybe there is an FTX system, maybe there is unventilated attic, maybe the roof has additional insulation.

one has to know the conditions in order to know what measures may need to be taken.
no one says there is no risk of damage, what I am saying is that it can be managed.

however, if you want to add insulation, you should not use wood shavings but other materials, wood shavings are bad for several reasons and should never be used. (there are special cases when you can use it)

Very unlikely with a vapor barrier, negative pressure, and FTX based on the first post.

 

[fribygg]

What does one do?

Costs money and uses electricity?
In a house from 1920, it is likely better to burn and keep the chimney warm, a pellets or wood boiler in the basement or a good stove with a catalyst on the living floor that provides the house's heat without electricity and gives a warm chimney, which is positive for both the ventilation and the climate of the attic.

 

[Aunty]

What does one of those do?

Costs money and uses electricity?
In a house from 1920, it's probably better to burn and keep the chimney warm, a pellet or wood boiler in the basement or a good stove with a catalyst on the living floor that can provide the house's heat without electricity and gives a warm chimney which is positive for both the ventilation and the attic's climate.

so you're going to burn all summer?

 

[fribygg]

however, if you want to add insulation, you should not use wood shavings but other materials, wood shavings are bad for several reasons and should never be used. (there are special cases when it can be used)

Therefore, I suggest topping up the existing sawdust, it has proven to work well in TS's house but the existing layer is apparently too thin for today's needs.

 

[fribygg]

so you're going to burn all summer?

How is it relevant what I do for the OP's question?

 

[nybyggarn3]

so you are going to burn all summer?

so you are going to burn all summer?

Costs money and uses electricity?
In a house from 1920, it is likely better to burn and keep the chimney warm, a pellet or wood boiler in the basement or a good stove with a catalyst on the living floor that accounts for the house's heat without electricity and provides a warm chimney that benefits the ventilation as well as the climate of the attic.

What?
One should be aware of the risks when praising the benefits and making a decision. If you don't believe there are risks with increasing insulation on old attics, you can always try googling it.

 

[Aunty]

Therefore, I suggest refilling with existing sawdust, it has proven to work well in the TS house but the existing layer is apparently too thin for today's needs.

but why sawdust, it's a poor solution that should no longer be used? there are much better alternatives in every way.

 

[Aunty]

What?
One should be aware of the risks when praising the benefits and making a decision. If you don't believe that there are risks with increasing insulation in old attics, you can always try googling.

but who said that there aren't any risks?