Insulation of the attic

2011-10-14 16:55:26

Hello everyone!

The roof of our terraced house has been insulated with mineral wool from the builder up to below the ridge.

Subsequently, about 1.50 m below the ridge, an attic floor was laid out using plywood panels on cross beams, which the builder seals underneath only with drywall panels to the underlying later heated living rooms.

The attic is intended to serve solely as storage or a storeroom and is therefore unheated. The attic will be accessible via the staircase using a pull-down ladder.

My question is: Should I additionally insulate the attic with mineral wool or similar material between the plywood panels and the drywall panels or not? What advantages or disadvantages could such insulation have?

I look forward to constructive advice!

Kind regards

2011-10-25 12:41:39

Hello, I'm not an expert, but I'll just answer...

We have insulated both the attic and the intermediate ceiling. I don't see any disadvantages with this principle. The only thing I'm not quite sure about is whether the insulation of the intermediate ceiling is allowed to be "in front of" the vapor barrier of the roof. Your existing vapor barrier will probably run up to the ridge. Our vapor barrier runs below the intermediate ceiling.

Maybe there is someone here who knows about this....

2011-10-25 17:32:26

Hello everyone!

The roof of our terraced house is insulated with mineral wool by the developer up to just below the ridge.

Subsequently, about 1.50 m below the ridge, an attic floor was installed using plywood sheets on crossbeams, which is sealed on the underside by the developer only with drywall panels to the heated living rooms below.

The attic is intended to serve only as a storage or utility room and will thus remain unheated. The attic will be accessible via a pull-out ladder through the stairwell.

My question is: Should I additionally insulate the attic with mineral wool or similar material between the plywood and drywall panels or not? What are the possible advantages or disadvantages of such insulation?

I look forward to constructive advice!

Kind regards

Hello!

To my knowledge, you must either ventilate or heat an attic. After your conversion, this would no longer be the case.

The background is that warm, moist air from the living rooms passes through the hatch and/or gaps into the attic and condenses there - thus creating the ideal basis for mold.

Insulation (mineral wool) would worsen the problem because it thermally separates the rooms more strongly.

A vapor barrier (foil) would mitigate it because it reduces vapor diffusion.

If these are indeed plywood sheets, you should also pay attention to your weight.

Best regards, Tomtom.

2011-11-15 02:13:35

Hello

If you don’t insulate the suspended ceiling, you’re basically heating the room above as well, which is a waste of money.

If you insulate the suspended ceiling, you have to install a vapor barrier on the living space/ceiling side and seal the joints and connections to the walls.

We also insulated twice, and there is no abnormal moisture to be measured up there. But as a precaution, we set up moisture meters.

Meanwhile, the legislator even mandates what you have to insulate; unfortunately, I don’t know if that applies to new or old buildings.

Best regards Sven

2011-11-29 12:24:17

Hello We also insulated double, and no abnormal moisture can be measured up there. However, we have set up moisture meters as a precaution.

Hello, we have insulated like that too. My question here: From what (%) do you speak of abnormal moisture? How many percent do you measure?

2011-11-29 13:56:52

Have a moisture content of 45-55%

and everything between 40-65% is normal, at least that's what it says on the moisture meter.

Best regards Sven

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Insulation of the attic

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TomTom1

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