Waterproofing bricks

[ScreamingBeans]

Is it a good idea or does it stop them from breathing?

Depends on construction and age of the house?

1880s either London or yellow stock apparently

It’s a bad idea. Bricks are porous. Moisture moves through tiny capillaries. Blocking these or sealing the surface will lead to the moisture getting trapped = damp. Also cracking in winter when it freezes.

What @Handsnotwands said.

Coating on our bricks (same age) has only caused problems.

Thanks all I decided against