ᐅ Pull-down attic ladder to an uninsulated attic space

Hello,

autumn is approaching, and we need to get moving on installing a 140 x 70 cm (55 x 28 inches) attic access hatch.

We have received offers for

- the Dolle clickFIX at €350 with a U-value of 0.49
- the Dolle clickFixThermo at €599 with a U-value of 0.39. Due to a regularly offered discount, the price could likely be reduced to just under €500 with some patience.

We are still waiting for other offers, but Dolle seems to be good quality, and the installation sounds fairly easy.

In your opinion, is it worth paying at least €150 more to improve the U-value of this relatively small surface area by 0.1? The frame is insulated with 22 cm (9 inches) WLG 035 stone wool.

That is approximately 1 m² (11 ft²) of surface area. Assuming an average temperature difference of 15°C (27°F) to the attic, about 1.5 watts pass through. Over a heating period of 4000 hours, that amounts to 6 kWh. Gas costs about 35 cents, and a heat pump (assuming an annual performance factor of 4) costs around 45 cents.

The payback period is therefore likely to be significantly longer than the expected service life of the pull-down attic ladder.

We also have a standard ClickFix, which is quite poor quality and not perfectly airtight.
However, unfortunately, I don’t know and didn’t know what would be better.
The U-value is probably not a relevant criterion.

Oki doke, then I can safely go with the cheaper option.

Well, Dolle seems to be quite common here. But I don’t really know a better alternative...

The important factor for attic ladders is not the decimal value of the U-value. As @Scout has already calculated.

More important is the correct installation without thermal bridging and ensuring it closes tightly. Air leakage losses are often much greater than heat transfer alone. Therefore, install it stress-free within the ceiling insulation layer and check that all sealing gaskets make proper contact.

Hello everyone,

I’m reopening this thread if that’s okay.

Which attic ladder do you have, and how satisfied are you with it? I need to order one today and I’m still undecided about the manufacturer.