ᐅ Are 36.5 cm hollow clay bricks W12 sufficient without additional insulation?

Hello,

is it still possible to meet current regulations using a 36.5 cm (14.4 inches) W12 perforated brick without additional insulation?

The plan is for a townhouse with 192 m2 (2,067 sq ft), an air-to-water heat pump, and a ventilation system.

If not, which bricks are commonly used today when building without extra insulation?

No KFW subsidies will be applied for.

Thank you in advance.

You can still build with a wall thickness of 36.5 cm (14.4 inches) today. There are brick variants with different compressive strength classes and similar properties; in some cases, one variant meets requirements such as the insulation level for KfW55, while another only meets the legal minimum. If you are not flexible in this regard, you can use aerated concrete instead of porous brick, or switch to a wall thickness of 42.5 cm (16.7 inches). Keep in mind my brick-building mantra: choose the brick according to the builder, not the other way around.

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The specified brick has a U-value of 0.30.
I seriously doubt that this is sufficient.
However, there are bricks with this material thickness that should be adequate or even meet KfW standards. A 365mm (14 inches) T9 brick should be heading in the right direction. Or a filled one.

guckuck2 schrieb:

The specified brick has a U-value of 0.30.
I doubt that is sufficient.
However, there are bricks with this material thickness that should be adequate or even meet KfW standards. A 365mm (14.4 inches) T9 brick might be heading in the right direction. Or something filled.

Our house will be built using Poroton T09d 36.5 cm (14.4 inches). This is sufficient for KfW 55. And that with only an air-to-water heat pump. However, the windows are passive house windows, as these are important for KfW 55.

We have decided on a ground-source heat pump plus controlled mechanical ventilation.

Tom1978 schrieb:

This is how our house is being built. Poroton T09d 36.5 cm (14 inches). It meets the requirements for KfW 55 standard. And this only with an air-to-water heat pump. However, the windows are passive house windows because they are important for KfW 55.

There are two key values that play an essential role.
The first is heat loss, which can be controlled through the insulating properties of the building envelope, for example, the choice of building material, insulation thickness, and glazing. It is important to find an economical balance here. Whether “passive house windows” are necessary or not is something the energy consultant will determine. However, they are certainly not absolutely required.
The second value is energy demand per square meter of living space. An air-to-water heat pump has no significant disadvantages compared to a ground-source (brine-to-water) heat pump and is more than sufficient on its own to meet the requirements. Mechanical ventilation with heat recovery is included in the calculation, and the presence of photovoltaic panels also has a slightly positive effect.

guckuck2 schrieb:

There are two key figures that play an essential role.
The first is heat loss. This can be controlled through the insulation properties of the building envelope, such as the choice of brick, insulation thickness, and glazing. It is important to find an economical balance here. Whether "passive house windows" are necessary or not is answered by the energy consultant. However, they are certainly not mandatory.
The other is energy demand per square meter of living area. An air-to-water heat pump does not have significant disadvantages compared to a ground-source (geothermal) heat pump and is more than sufficient on its own to meet the requirements. A controlled ventilation system with heat recovery is included in the calculation, and having a photovoltaic system also has a slight positive effect.

That is clear. We have no insulation in the walls—only the 36.5cm (14.4 inches) brick plus plaster.