Bricks blowing

[N. Thornton]

Hi

Interesting question: what causes bricks to blow out, their surfaces to expand and turn to powder?

Regards, NT

[Stuart]

Would it not be water ingress ,then the water freezing,expanding and doing the damage .? Stuart

[John Rumm]

In the case of soft victorian bricks, it is usually someone repointing them with a cement based mortar so that the mortar ends up harder than the brick so when things expand and contract something has to give.

[Harry Bloomfield]

N. Thornton wrote on Friday (13/02/2004) :

Usually porous bricks. They absorb moisture which then freezes, expands thus blowing the brick face out.

[Michael McNeil]

Some patterns of bricks can easily be put in upside down. You will sometimes se a wall that looks wet in ome places and dry in others shortly after rain. I imagine that if frost gets on the badly placed ones, the frost can blow the face off.

[Zymurgy]

Err, what's the alternative to cement based mortar ?!

P.

[N. Thornton]

lime based mortar

Regards, NT

[The Right Rev. Peter Parsnip]

The Lord alerted my mind to the presence of this EVIL article by Harry Bloomfield, and I thusly replied:

You know what I'm going to say now...