ᐅ Poroton T9 unfilled or Poroton T8 with mineral wool insulation?

Do you know the U-value of both types of bricks? Obviously, the additional cost of 5000 (including currency) takes several years to pay off purely through heating cost savings, depending on the type of heating system and the development of energy/electricity prices.

However, the more massive the house, the longer it stays warm in autumn and cool in early summer because of its thermal mass. It also reduces external noise more effectively. Additionally, with more solid masonry, there is more material left in the outer wall for installing water pipes or other utilities (which can then be better soundproofed, etc.).

Of course, it ultimately depends on whether these relatively small benefits are worth the additional 5000.

I have the 42 mm (1.7 inches) unfilled and, as of today, would choose the filled 36 mm (1.4 inches) for acoustic reasons.

Snowy36 schrieb:

I have the 42 cm (16.5 inches) non-filled blocks, but as of today, for soundproofing reasons, I would choose filled 36 cm (14 inch) blocks.

How close to a busy street do you live for that to make a noticeable difference for you?

annab377 schrieb:

Isn't the unfilled one the U8?

What wall thickness do you want to use @Annika90


**Edit: I’m interested in a 49cm (19 inches) brick thickness.

I checked on the Schlagmann website, for example:

• T7 with a U-value of 0.14 (unit price according to Schlagmann about 8.5 EUR)
• T8 with a U-value of 0.16 (unit price according to Schlagmann about 8 EUR)
• U8 with a U-value of 0.16 (unit price according to Schlagmann about 13.3 EUR)

The T7 and T8 are filled with perlite. The U8 is the one with many small chambers, which are supposed to break relatively easily during shell construction (see picture).

I don’t understand the pricing at all. The perlite-filled bricks, which are supposed to be more stable, clearly cost less than the air-filled one? Who wouldn’t choose the perlite brick (whether T7 or T8) then??


Image from schlagmann(.)de

Hey,

we have the U8 42.5cm (17 inches).
You can forget the prices listed by Schlagmann.
Go to your building materials supplier and ask for a quote (of course, calculate square meters or quantity beforehand).
For us, the brick cost about 3.50.

Selbstbau schrieb:

we have the U8 42.5cm (17 inches).

Have you already started / did you have any issues with the fragility of the U8?

annab377 schrieb:

Have you already started / did you have any issues with the fragility of the U8?

We built in 2017/2018. During the masonry work, we didn’t have any problems with the whole blocks. However, the cut blocks were quite fragile. Around 20 blocks broke in our hands, which I still consider acceptable. Chasing or milling grooves for electrical wiring also went quite smoothly... always with care and common sense.