Aerated concrete / brick / monolithic construction - who is familiar with it?

Thank you for your response.

The decentralized Lunos E2 with heat recovery is quite nice, but I would be more convinced if a device did not make hammering noises during operation (this started after 2 years).

How do you perceive the noise that comes from the system from the street into the interior? (Starting cars, conversations, playing children ...)

In 2013/2014 we achieved a monolithic KFW55 with 36.5 aerated concrete @ 0.08 lambda value.

May I ask how much kwh/(m2*a) final energy demand you have for heating and hot water? Even if you cannot easily transfer that to other houses ...

We live at an altitude of just under 300m. The house is rather simple in shape. Normal gable roof without dormers or skylights (one window per room on the gable side on the upper floor).

Styrofoam was not an option for various reasons, hence the rather expensive monolithic plan blocks with Lambda 0.08.

Size: 111 sqm living area. Exterior wall: 36.5 cm Ytong // Lambda 0.21 W/m²K Floor slab insulated with XPS // 0.21 W/m²K Ceiling on the upper floor sloped with 24 cm // Ceiling insulated with 34 cm mineral wool // 0.12 W/m²K The door + windows are triple glazed and gas-filled // Overall including frame 1.05 W/m²K.

Heat generator: Gas condensing boiler: Viessmann Vitodens 300 System control: Vitotronic 200 Solar 5 sqm: Vitosol 200-F solar storage tank: Vitocell 100-W 300 liters.

The solar system is only for hot water (without heating support). Our gas boiler is turned off for heating from May to September and uses about 100 kWh over the summer. In winter, the solar system hardly manages to heat the hot water (2 people), so it usually runs on gas.

Ventilation is done via decentralized Lunos e² with 90% heat recovery.

Consumption (heating + hot water) In the first year (19.10.14-19.10.15) 9,900 kWh gas In the second year (19.10.15-23.10.16) 7,730 kWh gas In the third year (23.10.16-09.05.2017) 7,282 kWh gas. So it settles at about ~8,100 kWh.

That currently means about €31 heating costs for the house. We have set 23°C throughout the house.

Overall, we are very satisfied. Of course, the energy certificate states a lower consumption than we actually have. But they also calculate with low temperatures below 20°C...!

There is no night shutdown and nothing ever turns off or regulates down otherwise.

The Lunos vents of course have an influence in that voices / chatter / screeching are perceived more clearly. I will close the hole with the defective device in the next few days with a cut-to-size piece of EPS, the rest will remain on. Replacing the device is too expensive for me, plus I ventilate this room often anyway after use.