maxpd
2022-07-11 13:11:01
- #1
Hi everyone,
I have a 20sqm underground garage, whose entrance is below ground level, but the rest is above ground (5sqm against soil, 5sqm against outside air).
I want to convert this room into an office/gym. Permission has been granted.
Due to the low ceiling height (216cm) I didn’t want underfloor or ceiling heating, but rather want to try wall heating.
The house is heated with an oil condensing boiler and radiators.
Because of the gym, an air conditioning unit is planned in the future.
Here are pictures of the walls (ignore the red cross):
I believe the black spots in the corner are not mold. Therefore, close-up shots are attached.
The wall is 36cm thick, from 1964, and according to the architect’s plans built with cinder blocks. When the windows were replaced, I think they used cinder hollow blocks.
Now I planned the following wall structure:
On the existing wall as it is (exposed, plastered and painted), apply bonding agent
(waterproof slurry against moisture from the soil – the wall remained dry after recent heavy rain)
Apply 3cm XPS insulation
Wall heating
Clay plaster
Total structure 5-6cm.
Cost < €1600
I only fear that by using the bonding agent as a practically "diffusion-tight" layer I bring the dew point inside and thus cause mold behind the insulation. According to this calculation:
An alternative would be the following structure:
Remove all existing plaster layers
Apply lime bonding plaster
Insulating plaster
Wall heating
Fine lime plaster
Total structure 7cm
Cost > €2500
Advantages:
The lime insulating plaster could absorb and release moisture.
Possibly a more natural indoor climate.
Disadvantages:
Significantly more effort.
Insulating effect is lower than with XPS.
Price significantly higher.
What do you think?
Another alternative would be to install the heating on an interior wall, thus avoiding a large temperature gradient on the exterior wall, although this is not usual.
Here is also my parallel floor planning:
Best regards
maxpd
I have a 20sqm underground garage, whose entrance is below ground level, but the rest is above ground (5sqm against soil, 5sqm against outside air).
I want to convert this room into an office/gym. Permission has been granted.
Due to the low ceiling height (216cm) I didn’t want underfloor or ceiling heating, but rather want to try wall heating.
The house is heated with an oil condensing boiler and radiators.
Because of the gym, an air conditioning unit is planned in the future.
Here are pictures of the walls (ignore the red cross):
I believe the black spots in the corner are not mold. Therefore, close-up shots are attached.
The wall is 36cm thick, from 1964, and according to the architect’s plans built with cinder blocks. When the windows were replaced, I think they used cinder hollow blocks.
Now I planned the following wall structure:
On the existing wall as it is (exposed, plastered and painted), apply bonding agent
(waterproof slurry against moisture from the soil – the wall remained dry after recent heavy rain)
Apply 3cm XPS insulation
Wall heating
Clay plaster
Total structure 5-6cm.
Cost < €1600
I only fear that by using the bonding agent as a practically "diffusion-tight" layer I bring the dew point inside and thus cause mold behind the insulation. According to this calculation:
An alternative would be the following structure:
Remove all existing plaster layers
Apply lime bonding plaster
Insulating plaster
Wall heating
Fine lime plaster
Total structure 7cm
Cost > €2500
Advantages:
The lime insulating plaster could absorb and release moisture.
Possibly a more natural indoor climate.
Disadvantages:
Significantly more effort.
Insulating effect is lower than with XPS.
Price significantly higher.
What do you think?
Another alternative would be to install the heating on an interior wall, thus avoiding a large temperature gradient on the exterior wall, although this is not usual.
Here is also my parallel floor planning:
Best regards
maxpd