Instead of insulation, erect a second brick wall

A comprehensive insulation is planned for our house. Currently, we have a brick wall with 25 cm, partially still in shell construction, otherwise lime plaster. Of course, a thick layer of insulation must be applied. Now the idea has developed for us to erect a second 25 cm clay brick wall instead of the common, because cheapest, polystyrene insulation, possibly with 5 cm of stone wool insulation or something else in the gap. Has anyone had experience with this construction method and can anyone also inform us about possible disadvantages?

Well, hard to say, clay walls alone don’t bring that much, but they do have charm because they are basically still single-layered! Well, with external insulation, careful planning is necessary because the house may become too airtight, possibly then considering a ventilation system. Core insulation at first glance probably the nicest, maybe also clay wall + core insulation + Klinger = an option?

Hello Blurboy! Thank you for your answer Actually, we had thought that the house would then be plastered. Brickwork is not so common in our area (Upper Austria). As bricks, we would take one with air chambers, which are usually offered, for example, by Wienerberger or the Senftenbacher Bio 25 VZ. processed with Dry-Fix or thin-bed mortar The advantage would be that the elaborate work of mixing mortar is eliminated. Which would considerably simplify the matter.

Hello,

...Now the idea has come up with us to build a second 25 cm clay brick wall instead of the common and cheapest polystyrene insulation, possibly with 5 cm of rock wool insulation or something else in the intermediate space.

Too bad about the effort. It hardly brings any energy efficiency. Best regards.