Hello everyone,
I currently need to decide on the thickness of our ETICS (External Thermal Insulation Composite System) for the facade. According to the energy-saving regulations, I need at least 12cm (5 inches) on my precast concrete elements.
I have now received quotes for 14cm (5.5 inches), 16cm (6.3 inches), and 18cm (7 inches) as well.
According to the architect, the energy demand differs as follows:
Thickness Final Energy Demand Primary Energy Demand
12 cm (5 inches) 17.70 31.87
14 cm (5.5 inches) 17.66 31.78
16 cm (6.3 inches) 17.04 30.67
18 cm (7 inches) 17.01 30.62
The units are kWh/m²a.
So, what now?
The house has a full basement. Basement and roof insulation are not to be considered here. Geothermal energy will be used as the energy source, and a controlled mechanical ventilation system with heat recovery will be installed. The windows have triple glazing. Overall, about 220 m² (2370 ft²) of living and usable space will be fully heated (attic insulated but not heated).
Do I now have to multiply the difference by the living/usable area, apply my average kWh price, and that will be the additional annual cost? Or am I thinking about this incorrectly?
Thanks and regards,
Markus
I currently need to decide on the thickness of our ETICS (External Thermal Insulation Composite System) for the facade. According to the energy-saving regulations, I need at least 12cm (5 inches) on my precast concrete elements.
I have now received quotes for 14cm (5.5 inches), 16cm (6.3 inches), and 18cm (7 inches) as well.
According to the architect, the energy demand differs as follows:
Thickness Final Energy Demand Primary Energy Demand
12 cm (5 inches) 17.70 31.87
14 cm (5.5 inches) 17.66 31.78
16 cm (6.3 inches) 17.04 30.67
18 cm (7 inches) 17.01 30.62
The units are kWh/m²a.
So, what now?
The house has a full basement. Basement and roof insulation are not to be considered here. Geothermal energy will be used as the energy source, and a controlled mechanical ventilation system with heat recovery will be installed. The windows have triple glazing. Overall, about 220 m² (2370 ft²) of living and usable space will be fully heated (attic insulated but not heated).
Do I now have to multiply the difference by the living/usable area, apply my average kWh price, and that will be the additional annual cost? Or am I thinking about this incorrectly?
Thanks and regards,
Markus
M
MIA_SAN_MIA__14 Mar 2018 12:11Unfortunately, I cannot (yet) provide any input on your specific question, but why are you using precast concrete elements above ground as walls?
We coordinated with our architect and selected a company to construct the shell using precast concrete elements, including a waterproof basement. It will be assembled within the next 2 weeks – the topping-out ceremony is planned for the end of April.
This was about the construction timeline, and we liked the concept.
Regards,
-Markus-
This was about the construction timeline, and we liked the concept.
Regards,
-Markus-
Setting a lot in advance: so-so.
Except for the sensibly placed openings for my cable routing, the flush-mounted boxes cast into the ground floor ceiling for the spotlights, and the openings necessary for drainage, basically nothing.
Electrical outlets are normally channeled—here you just have to pay attention to the thickness.
Any contributions to this topic 🙂?
Regards
-Markus-
Except for the sensibly placed openings for my cable routing, the flush-mounted boxes cast into the ground floor ceiling for the spotlights, and the openings necessary for drainage, basically nothing.
Electrical outlets are normally channeled—here you just have to pay attention to the thickness.
Any contributions to this topic 🙂?
Regards
-Markus-
What is your goal? Optimal cost-effectiveness? In that case, you need to consider the extra cost of thicker insulation.
However, the calculation isn’t that simple. Better insulation means lower heating demand, which can reduce the length of boreholes needed and possibly even allow for a smaller heat pump. It can be worth it, but there are several “ifs” involved.
Then there are factors like comfort. Does the wall feel cold in winter? Cold enough that you don’t want to lean your back or neck against it? I find this especially important in basements that might be used as living spaces later on, regardless of the cost-effectiveness discussion.
Also, once the insulation is installed underground, you generally can’t access it again without significant expense. Maybe it’s better to invest a bit more there?
In the end, this is a fundamental decision. If you want the minimum, stick with 12cm (5 inches). It will still provide comfortable living conditions. If you expect rising energy costs or have other reasons, go thicker.
A rough estimate is that each additional centimeter of insulation thickness costs about €1.50 (about $1.65) net per square meter.
However, the calculation isn’t that simple. Better insulation means lower heating demand, which can reduce the length of boreholes needed and possibly even allow for a smaller heat pump. It can be worth it, but there are several “ifs” involved.
Then there are factors like comfort. Does the wall feel cold in winter? Cold enough that you don’t want to lean your back or neck against it? I find this especially important in basements that might be used as living spaces later on, regardless of the cost-effectiveness discussion.
Also, once the insulation is installed underground, you generally can’t access it again without significant expense. Maybe it’s better to invest a bit more there?
In the end, this is a fundamental decision. If you want the minimum, stick with 12cm (5 inches). It will still provide comfortable living conditions. If you expect rising energy costs or have other reasons, go thicker.
A rough estimate is that each additional centimeter of insulation thickness costs about €1.50 (about $1.65) net per square meter.
Similar topics