ᐅ Is Insulation Necessary for Poroton Bricks?

Hello everyone,

We are building a single-family house with an architect, without KfW certification. Poroton bricks (the ones with cavities), about 35 cm (14 inches) thick, will be used along with triple-glazed windows. Underfloor heating and a heat pump are also part of the plan.

According to the architect, additional external insulation is not necessary because the bricks have low thermal conductivity. Only around the roller shutter boxes will Styrodur insulation be installed. Since he advised us against a central ventilation system due to the costs—and I now regret not choosing it—I am now unsure about the insulation as well.

What are your thoughts?

Which type of Poroton is it exactly?
There are quite significant differences.

Then try searching for answers here in the forum…. Sorry that you are getting this now, but answering the same questions repeatedly is somehow no fun…. You definitely don’t need insulation in that case. What you do need, however, is a filling… mineral wool or perlite. Sound transfers through these cavities way too much… both from inside to outside and within the single-family house.

Ok, the architect never mentioned any filling in relation to soundproofing. Now it’s too late for that anyway.
Insulation would still have been possible.
We specifically asked about soundproofing inside as well, and he said that wouldn’t be a problem.
Outside is not so critical, as we are located in a quiet area without through traffic.

DerMitDemFH schrieb:

Ok, the architect never mentioned any kind of infill regarding soundproofing. Now it’s too late for that anyway.
Insulation would still have been possible.
We specifically asked about soundproofing inside, and he said it wouldn’t be a problem.
The outside isn’t so critical since we’re in a quiet area without through traffic.

You’re definitely not the only one if that makes you feel better. We also live in a quiet location, and it’s not like it drives you crazy, but the soundproofing could definitely be better (passing cars, children playing). At this stage, make sure you don’t have any important interior walls thinner than 17cm (7 inches). That makes a noticeable difference indoors. Above all, make sure there’s no water source (shower, toilet) located directly next to a bedroom or similar space. If it’s planned differently now, you’ll need to come up with a solution like a secondary wall or something similar.

But your original question is answered: you definitely don’t need insulation (-: and you wouldn’t want it anyway, especially if you don’t have a ventilation system.

You don’t need external insulation. If you still want to do something, then choose exterior walls of 42cm (16.5 inches) thickness or 36.5cm (14.4 inches) with insulation on the inside. We also have standard Poroton bricks without insulation, and the soundproofing isn’t particularly great but also not bad enough to cause constant complaints. For interior walls, as mentioned before, don’t use 11cm (4.3 inches) bricks. I would go with 17cm (6.7 inches) or calcium silicate bricks.

Otherwise, I think Poroton offers a good compromise between soundproofing and thermal insulation.

Ask about your ventilation concept. I guess you’ll have window frame vents. We also use these combined with exhaust vents in wet rooms and the utility room. Overall, that’s acceptable for a residential area.