Hatch cover floor ladder experiences

Which pull-down attic ladder is actually installed? Is the insulation placed on the concrete ceiling inside the cold roof? We also have a pull-down ladder into the cold roof, and one must be aware that this breaks the thermal envelope of the house and that attention should be paid to the corresponding U-value of the ladder. We have one with a double all-around seal and an insulated cover (about 10-12 cm, I would estimate). Condensation has not been an issue so far.

How do you know that it isn’t the case? Most attics are very dimly lit, so you easily overlook it. And you don’t go up there that often either. As long as it’s only a little bit of moisture, you don’t notice it that well… …Basically, I would say that the cover must be able to handle that. The intended use is exactly between humid-warm living room air and cold-dry attic air. Although we are talking here about absolute moisture. Relatively, we have 70+% in the attic. No wonder, because it roughly follows the outside air (the attic is not completely airtight) and that often has over 90% during damp-cold weather.

That is exactly the problem with this constellation. Many people open the attic hatch in winter to get Christmas lights, etc., and then put them away again, repeatedly letting warm air flow into the cold roof. It then cools down there, and condensation occurs. I recommend placing an adsorption dryer up there with a built-in timer or connected to a time switch and running it for 2-3 hours after leaving the attic. We have already implemented this and reduce humidity from 70-72% down to 62-64%. The cold roof is tight enough to rot if you don’t keep an eye on it. We only observe real air exchange during storms because then it pushes through the dry ridge and the gaps in the wood fiber boards. The cold roof in modern, quite airtight new buildings is technically not intended as usable space, but many (including us) wish for that because space = money in the end. That’s why corresponding countermeasures are all the more important. You don’t have this problem in summer.

A true cold roof should not be sealed tight at all. It should really have a draft. It’s the same for me. I have no problems with mold or just condensation. But during storms, I do have issues with rattling ghosts (clattering boards that I store there).

There is usually more than one problem. The issue with the open hatch is of course one, although I have not been able to understand so far that it has more influence on the humidity in the attic than the weather. Another problem is that any leak at the hatch also leads to condensation. For me, the problem is less the seal of the hatch itself than the installation of the frame in the ceiling. This has already been reworked twice and I am not yet quite sure whether it is really sealed now. Ideally, a cold roof is planned either with small windows on the gable side or with ventilation elements. Dehumidifiers are of course also an option, but the problem then is of course the condensate.

Which attic ladder is actually installed? Is the insulation located on the concrete slab inside the cold attic? We also have an attic ladder to the cold attic and you have to be aware that it penetrates the thermal envelope of the house and you should pay attention to the corresponding U-value of the ladder. We have one with a double circumferential seal and an insulated cover (I would estimate about 10-12 cm). Condensation has not been an issue so far.

From the attic to the loft we have drywall and above that is insulated with WLG 035 mineral wool. On the loft there are OSB panels again so that it is fully walkable (except for the edges and the part where the side gable of the house is located). The ladder should be a Dolle Click Fix in 120x70.

That’s exactly the problem with this configuration. Many people open the attic hatch in winter to get the Christmas lights, etc. and put them away, thus repeatedly letting warm air into the cold attic. It then cools down there and condensation occurs. I recommend placing an adsorption dryer up there with a built-in timer or connected to a timer switch and letting it run for 2-3 hours after leaving the attic again.

I’ll keep the dryer in mind, thanks!

For me, it is less the seal of the hatch itself that is the problem but the installation of the frame in the ceiling. This has already been rectified twice and I am still not quite sure if it is really airtight now.

Well, the carpenter checked the frame first and said that everything was done correctly there and the seal is also fine.

Is there a vapor barrier foil between the drywall and insulation?