ᐅ Planning a Single-Family Home Construction – Building Energy Act 2023
Created on: 5 Nov 2022 22:01
H
Hansi H.
Hello everyone!
We are currently in the planning phase for a solid single-family house with a living area of 154m² (2 full floors), 77m² (830 sq ft) of usable basement space, and a total enclosed volume of 1010m³ (35,670 ft³). Due to ongoing site development work, construction is expected to start around August 2023.
In August, we signed the turnkey construction contract based on the 2020 Building Energy Act standard. Since the KfW funding programs were put on hold, we honestly didn’t focus much on energy efficiency, assuming the standard would be sufficiently high. Now, during further planning, we came across the upcoming changes to the 2023 Building Energy Act, which, as far as we understand, have already been approved by the Federal Council?!
The planned specifications are:
- District heating as the energy source
- Triple-glazed windows (U-value 0.6 W/m²K)
- Exterior walls made of 36.5cm (14 inches) brickwork (0.09 W/mK)
- Central mechanical ventilation with heat recovery, including the basement
- Basement with a 25cm (10 inches) thick floor slab and 25cm (10 inches) concrete wall thickness plus 12cm (5 inches) perimeter insulation (0.035 W/mK)
- Roof with 20cm (8 inches) cavity insulation (0.035 W/mK) plus 60mm (2.4 inches) wood fiber board insulation above rafters
The necessary changes to achieve a “funding-eligible” KfW55 house are currently priced at around €15,000. Honestly, I would have preferred to invest that money in a photovoltaic system, if it really was available.
As far as I understand, the 2023 Building Energy Act changes do not affect the building envelope requirements but rather the “primary energy demand.” Does anyone know if these are mainly calculation changes, or do the new rules actually require investments equivalent to those for a KfW55 house? Are the anticipated energy savings really about 15% compared to a KfW70/2020 Building Energy Act standard, making the extra costs definitely worthwhile, or is this just wishful thinking?
We are a bit annoyed that the company did not inform us about these expected changes and the resulting clear cost increase before signing.
Thanks very much for your opinions!
Best regards,
Hansi
We are currently in the planning phase for a solid single-family house with a living area of 154m² (2 full floors), 77m² (830 sq ft) of usable basement space, and a total enclosed volume of 1010m³ (35,670 ft³). Due to ongoing site development work, construction is expected to start around August 2023.
In August, we signed the turnkey construction contract based on the 2020 Building Energy Act standard. Since the KfW funding programs were put on hold, we honestly didn’t focus much on energy efficiency, assuming the standard would be sufficiently high. Now, during further planning, we came across the upcoming changes to the 2023 Building Energy Act, which, as far as we understand, have already been approved by the Federal Council?!
The planned specifications are:
- District heating as the energy source
- Triple-glazed windows (U-value 0.6 W/m²K)
- Exterior walls made of 36.5cm (14 inches) brickwork (0.09 W/mK)
- Central mechanical ventilation with heat recovery, including the basement
- Basement with a 25cm (10 inches) thick floor slab and 25cm (10 inches) concrete wall thickness plus 12cm (5 inches) perimeter insulation (0.035 W/mK)
- Roof with 20cm (8 inches) cavity insulation (0.035 W/mK) plus 60mm (2.4 inches) wood fiber board insulation above rafters
The necessary changes to achieve a “funding-eligible” KfW55 house are currently priced at around €15,000. Honestly, I would have preferred to invest that money in a photovoltaic system, if it really was available.
As far as I understand, the 2023 Building Energy Act changes do not affect the building envelope requirements but rather the “primary energy demand.” Does anyone know if these are mainly calculation changes, or do the new rules actually require investments equivalent to those for a KfW55 house? Are the anticipated energy savings really about 15% compared to a KfW70/2020 Building Energy Act standard, making the extra costs definitely worthwhile, or is this just wishful thinking?
We are a bit annoyed that the company did not inform us about these expected changes and the resulting clear cost increase before signing.
Thanks very much for your opinions!
Best regards,
Hansi
This is how it stands in the architect’s volume calculations. The building footprint is 100m2 (1,076 sq ft), rooms are in the basement with a height of 2.50m (8.2 ft), ground floor 2.60m (8.5 ft), upper floor 4.00m (13.1 ft) at the ridge, 2.50m (8.2 ft) at the exterior wall. The maximum height at the ridge might still be reduced to 3.50m (11.5 ft), but it is currently open.
But you’re right, when you roughly calculate it, the volume will naturally be less. Are exterior walls and roof structure included in this calculation?
But you’re right, when you roughly calculate it, the volume will naturally be less. Are exterior walls and roof structure included in this calculation?
Hansi H. schrieb:
Rooms in the basement are 2.50 m (8 ft 2 in), ground floor 2.60 m (8 ft 6 in), upper floor 4.00 m (13 ft 1 in) at the ridge, 2.50 m (8 ft 2 in) at the exterior wall. The maximum height at the ridge might still be lowered to 3.50 m (11 ft 6 in), but it is currently open. That is quite spacious already!