Thinking aloud on practical measures to take in an attic

[Garald]

[Background: a major renovation is drawing to a close - and it finally got cold (-2 C), so I just got myself a thermal camera.]

 

I've already posted some of the pictures below. Now let me think aloud about what they mean and what practical measures may be taken. Please correct me if I am misinterpreting something or if I am being silly.

 

1. Unsurprisingly, the coldest bits are mainly the windows (especially the joints between the windowpanes and the frames). The only thing I can think of to improve the situation is to get thermal-insulation shades from Velux itself. I've already got *outside* shades, which are very helpful in summer. Inside shades (which we'd presumably be using at night, as they block light; will we actually remember to draw them?) would increase insulation by up to 25%, according to the manufacturer, and that isn't that much. They work mainly by reflective insulation (the only way in which thin material can have any significant effect, really). They aren't cheap.

https://www.veluxshop.fr/.../stor.../stores-plisses-isolants

See also: https://avosdim.com/store-isolant-pour-velux.html

If I were some sort of carpenter, I would consider creating some sort of sliding wooden shutters (a bit like barn doors in the ceiling). One can always dream.

2. 

 

Parts of the low walls, in particular near corners, are fairly cold (between 11 and 14C when the room is at around 18C and the outside temperature is -2 C or so). Now, I've been lining them with solid-wood bookcases that fit snuggly, and that actually seems effective (the bookcases show up as warm in the thermal-camera pictures, and it would make sense that having cellulose, wood and a thin layer of air in front of a wall would improve its insulation). What to do in left-over spaces?

Incidentally, this is a bit disappointing, as the spaces behind the low walls are supposed to be full of cellulose insulation. Perhaps the cellulose has settled? (Note how some of the low walls seem to be a bit colder towards the top.) Not sure how one could test that non-destructively.

It is also possible that there isn't a grave insulation defect here, and that the low walls are cold-ish simply because they get no direct sunlight. OTOH, the bookcases are not cold.

 

I can see two possibilities:

(a) made-to-measure bookcases. Downside: generally expensive, and would not fit well with the kit furniture I've got. (The made-to-measure make-them-yourself bookcases from Germany I got recently are not so expensive, but they lack backs.)

(b) cork. It's not cheap, but apparently one can get cork panels of non-trivial thickness for less than a fortune. 4cm of cork should add 1 to the R-value, and I imagine 3cm of cork + 13mm should do not much worse:

https://www.amazon.fr/Italfrom.../dp/B08MTD16G6/...

My understanding is that cork is non-toxic and not much of a fire hazard (well, fire class E, but books are presumably worse). Installing panels of this type (after cutting them to the right size and so as to allow for the use of electrical sockets) sounds like a reasonable DIY project (meaning I would possibly pay someone to help me). If I don't like the white of the plaster cover, I can always put wallpaper on it. Just an idea.

(Of course there's also decorative cork that can be left uncovered, but that's more expensive, at least if any significant thickness is wished for.)

 

3. There are some cold zones in ceiling-wall edges and the like. Not sure what I can do there. I might be tempted to put a couple of tapestries on the ceiling, but that may count as a fire hazard (especially when it comes to the tiny staircase leading to the attic). 

 

 

[Andehh]

I wonder if a few small holes drilled in these 'cold spot' areas, and using low expansion expanding foam squirted in could help?

 

Maybe a discrete trial in a tucked away area?

[Garald]

9 minutes ago, Andehh said:

I wonder if a few small holes drilled in these 'cold spot' areas, and using low expansion expanding foam squirted in could help?

 

Maybe a discrete trial in a tucked away area?

Interesting - what kind of foam exactly?