Summer heat protection: Differences in bricks

Hello everyone,

after the hot summer this year, the topic of "summer thermal insulation" has increasingly come into focus in our house planning. We were recommended a building with a T10 brick in this regard, as it is supposedly significantly better for summer thermal insulation than the "newer" highly insulating unfilled and filled bricks. However, apart from this statement, I cannot find any real specifications on this – on the website of a relevant manufacturer, the good summer thermal insulation of perlite-filled bricks is even advertised. So what is the truth here and which brick would you choose from the perspective of summer thermal insulation?

Best regards
ufr

Well, then I'll try to explain the principle:

Solid bricks nowadays are only used as exterior wall material in decorative places (especially as clinker), while for structural purposes, if bricks are used at all, then they are porous bricks with chambers.

These chambers are always filled with something - if with air, they are called "unfilled," because this filling is easily volatile and adapts most easily to the ambient air – and therefore also to its temperature.

Chambers filled with "materials" offer a more fixed distance to the properties of the brick webs – this "stop and go" of heat transfer, which must pass alternately through different materials, creates the braking effect that slows down the transfer. The effect is more intense, the greater the difference in their properties (especially density); and more consistent, the more stable the properties of the filling medium are – here, the air "filling" is the most variable.

The fillings I call "cream fillings," i.e. foams with granules, hold their position, while those with loosely poured granules settle and over time lower their density. After all, this settling in the chambers of individual bricks only occurs up to the next bed joint, while blowing into an air layer between two masonry shells settles further. Therefore, the latter is used only for "retrofitting" and "new" constructions prefer mat-shaped "fillings."

I don't quite understand your answer. Is then air-filled worse or better than e.g. perlite when it comes to thermal insulation? What would be the suggestion to the OP?

You get heat into the house mostly through windows and especially the roof. The tiles play a rather minor role.

Since the thermal insulation value of unfilled tiles can be just as good as that of filled ones, it does not matter whether they are filled or unfilled.

In the roof, the phase shift plays a major role. For the tiles, rather not.

Filled ones can already be better than unfilled ones. That's why they exist. But ultimately, the thermal transmittance coefficient is the same measurement value that keeps the heat inside in winter and keeps the heat out in summer. The mass and heat capacity of the different Poroton types are also close to each other, so it should not play a role.

I don't quite understand your answer.

That's the great thing about the internet: you can read slower than I write ;-)

Is air-filled then worse or better than, for example, perlite in terms of thermal insulation?

With air, the density gradient between the brick web and chamber is larger, but fluctuating.

What would then be the suggestion for the OP?

I am explaining the principle neutrally so that everyone can draw their own conclusions.

And don't forget: I explained the principle generally regarding heat transfer; here it is specifically about protection against incoming heat. Therefore, rightly points out that repelling heat entry here is more effective than relying on rapid dissipation. Especially since you can easily change tires between summer and winter, but not walls ;-)