Semi-detached house built in 1980 wall structure

Hello everyone,

I am starting the following thread for discussion here, as it surely fits better:



Wall construction:
Basement exterior walls: MZ150 III partially cast concrete
Upper floor exterior walls: 24cm pumice hollow block masonry with air layer and clinker brick facing.
Insulation of the preliminary exterior walls: In the air layer about 4cm stone wool mats, which are covered with an outer sealing membrane.
Gable walls: insulating aerated concrete backing, externally bonded with black slate on sealing membrane.
Waterproofing against earth moisture: insulating coating on concrete basin as well as 2x sanded felt in the layers of the exterior walls

I also have values from an energy demand calculation. It lists the following K-values (today U-values)

FB: 0.80
AW: 0.54
ED: 2.36
TR: 1.00

Can someone tell me what FB, ED, and TR mean?

My plan is to have the insulation between masonry and clinker checked, if necessary renewed, to insulate the gable wall from the outside and to insulate the roof anew.

To which trade should I turn regarding checking the insulation between masonry and clinker?

If the house was built in 1980, the thermal insulation standard from 1977 (today's Energy Saving Ordinance) was the requirement for the energy standard, which must be demonstrated in the thermal insulation certificate (attachment to the statics). Your values do not necessarily comply with these requirements. 0.54 W/m2K for the exterior wall would be quite good and would exceed the official requirements by far. According to rough calculations, however, it is correct (my value: 0.59 W/m2K, assumed HBL 1200 Kg/m3, the quality of the masonry is decisive. A lighter stone insulates better).

I can only interpret the other data ad hoc as well: FB (floor heating), the value would rather fit the basement ceiling. ED means nothing to me; the high/poor value would be typical for windows/glazing.

For an energy-efficient renovation, a condition survey is a prerequisite. Building damage/moisture damage, etc. must be identified and permanently repaired before the building insulation is revised/improved.

I always recommend commissioning an independent expert with this condition survey, preferably a combination of architect / structural engineer and energy consultant, who can also advise you on funding opportunities from BAFA/KfW. What I advise against is asking craft businesses for a free assessment of the situation and an offer. These companies are executing companies and not planners. Your renovation project must be planned in the overall context of the building: across trades.