Facade renovation, connection of cold roof

Till, many thanks for the proposal, here the effort is in proportion, we will confront the carpenter with it.

I did not want to generalize the opinion about energy consultants as a profession, my experience with the previous energy consultants and site managers was quite negative, the hourly rate here in CH is 130, so I can expect a pragmatic way of thinking and not statements like: photovoltaic is not worthwhile, one should rather redo the entire roof, etc. A new car is always the best solution, luckily most of us drive a used one. Maybe it is due to my poor preselection and lack of experience. In the end, with the consulting fees, I could at least have paid for the formwork action.

I will borrow the thermal imaging camera and see how it looks at -5/-10 degrees outside temperature in the corners of the rooms on the ground floor, because the previous owner had mold there and this must be avoided in the future.

I don't find 130 francs overpriced. My expert here in Germany charges 150€, and the salary structure and cost of living are somewhat different here. Of course, the quality has to be right ;)

You will only be able to properly solve the corner by insulating it from the outside. Alternatively, you can heat the spot from the inside to prevent moisture from condensing. In old buildings, the walls are cold, so at a certain temperature (search for dew point calculators), the humidity condenses on the walls. Corners are double thermal bridges and at the same time poorly ventilated.

As far as I know, the requirements are now higher here as well.

Unfortunately not. There are still TÜV courses with a subsequent exam and certification of the "alternative access route" Costs: 3400 EUR and a few weeks (I think four or five). You don't need a subject-specific degree for that, you can participate, for example, as a business economist. However, there are currently no dates for the seminar...

Yesterday a "consultant" came with a thermal imaging camera, one of those Flir attachments for 200 euros seems to work reasonably well, I think I'll get one of those myself. All thermal bridges were confirmed, in the room there are temperature differences between 16-19 degrees - 19 closer to the underfloor heating, 16 at the thermal bridges. But what really blew me away was that the expert recommended not doing anything to the facade at all, but rather considering thermal strips. The reasoning - in such an old building you usually can't seal everything properly and just shift the problems. Many experts, many opinions, I can't just heat the walls afterwards. What was useful though, the triple-glazed windows were probably installed with foam insulation 15 years ago. The reveal areas are therefore problem spots, we have to plan that well. The expert recommended waiting and replacing all windows, which is also a funny recommendation as far as implementation goes. He recommended leaving the roof as is, or rather not opening the eaves. But I can't really trust his statements, he didn't look behind the eaves, you just don't see any drastic transitions from the knee wall to the ceiling on the thermal image camera.

Attached is also a picture of the roof, knee wall... that looks quite "homogeneous".


And the windows from outside

and inside



Regarding the windows, I'm not sure if it's only the reveal areas (currently not insulated at all) or also the building fabric around the frame (cement, probably foam). Since we only wanted to install aluminum blinds on 5 of 11 selected windows, I wonder if roller shutters wouldn't be better. At least then you would have some insulation at night. I cannot understand or accept the suggestion from the 4th funny consultant to only do the facade in 10 years and then replace all windows (currently triple glazed). Until then I am supposed to work with heating strips. I looked at the heating strips and see no way to connect these retroactively to the underfloor heating circuit without tearing up the floor, especially since I want to lower my flow temperature later rather than raise it to 35. With electric heating strips the power consumption would probably be disproportionate, and in addition power lines would have to be laid. Exactly such recommendations really piss me off, not feasible, not practical and then the sentence - you should have involved me from the beginning of the renovation.

In the meantime, the VHF blowing-in facade (wood wool) is finished. Today I borrowed a Flir One Pro thermal camera attachment. When evaluating and comparing it with the old recordings (unfortunately not created with Flir but with Seek) - see above, I am struggling. Since the facade looks evenly on the thermal images from the outside, I assume that the blowing-in worked well. What I do not understand, however, is that when I take images from the inside, for example in the living room, the geometric thermal bridges are visible again. Temperature difference between 16-17 and 21 degrees. The windows are clear but I would not have expected the dark blue stripes at the wall junctions with a U-value below 0.2.



Good uniformity of the exterior facade... The reveals, front door, and canopy connection are as expected not well insulated.



The camera did not really convince me (the images are offset) and it displayed outdoor spots with -14 degrees, although according to the thermometer it was only -8. I probably cannot operate professional thermal cameras, or found none available for borrowing anywhere.

Since the facade looks even on the thermal images from the outside, I assume that the blowing in worked well. What I don’t understand, however, is that when I record inside, for example in the , the geometric thermal bridges are visible again.

With a VHF, you can say little from the outside with a thermal camera about whether it was fully blown in. Because of the ventilation, you have a cold facade with an even temperature distribution anyway. Only at the non-ventilated reveals can errors and leaks be detected there. Inside, you measured 16.3°C as the lowest value at -8°C outdoor temperature? That is not a bad or unexpected value at all. There is a keyword in the planning of insulation measures called "minimum thermal protection according to DIN 4108." This must be observed everywhere, also at thermal bridges, so that the risk of condensation and mold formation later on is low. For this, the surface temperature at every point must reach 12.6°C or more at the standard outdoor temperature (-8° to -15°C, depending on the region; you can check this for your location). That should be the case with you.

If your windows have only been installed with foam without an internal airtightness layer, and you feel slight drafts at the frame-to-window transition or at the windowsill, you can work on these areas again.

I don’t have a Flir myself, but I used one as an iPhone attachment a few years ago. The offset between the thermal image and the photo can, as far as I remember, be calibrated so that this does not occur.