Breeze block for outdoors?

[Harry Bloomfield]

I told breeze block is quite suitable for outdoor use, can anyone confirm this is the case and/or advise on an alternative light weight building block?

Its a small shed.

[Mary Fisher]

We used it for our garage about twenty years ago. Could be more. It has lots of supports for shelvings on the inner wall - I said 'garage' but used the term loosely. There wouldn't be room for a Dinky car in it never mind the smallest roadworthy one - even if it could reach that far on the drive :-(

It's still standing.

It doesn't even look bad, with it's white painted surface.

Mary

[Dan delaMare-Lyon]

Block structure - cement render outside - will last for years!

Cheers Dan.

[Harry Bloomfield]

It happens that Mary Fisher formulated :

Hi Mary,

Check your email inbox!

[Andrew Gabriel]

Real breeze blocks haven't existed since 1930's, so you'll need to be more specific about exactly which blocks you mean.

Thermal blocks do expand and contract slightly when they get wet and dry out, enough to cause plaster to crack or lose key and to crack the blocks themselves if layed wet and they dry after the mortar has set. Also, they act rather like a sponge.

There are probably better products available if you don't need the thermal properties, but I've never needed to investigate. Alternatively, a waterproof finish, such as a render with a waterproofing additive might be OK.

[Mary Fisher]

It's flagged. And in the queue.

Mary

[Guy King]

The message from Harry Bloomfield contains these words:

Thermalite do a block called "Trench", which is for underground use.

Personally I wouldn't use aerated concrete blocks anywhere they might get bashed - they really are very soft. My three year old was merrily bashing some offcuts the other day and she managed to break up quite a number of large bits into small bits[1]. They crumble too easily. Go for dense concrete blocks if it's exposed. Cladding would be sufficient to protect them.

[1] Did she clear up after her? Did she hell. Gets it from her brother - and I can't /imagine/ where he gets it from.

[Chris Bacon]

Concrete should be OK, I certainly would not use breeze blocks or aerated where it may get wet (and worse: freeze wet). You could use them above DPC with a good layer of waterproof stuff - timber, corrugated iron, cement render with waterproofing admixture - but...

[Christian McArdle]

Breeze blocks aren't usually available these days.

You could use aerated concrete blocks. Very light weight, but do look a bit skanky after a couple of years. I've got some in my garden creating a 30cm terrace to hold back the patio. I haven't got round to facing it with something nice looking. They've turned a nice shade of green, but are clearly holding out against the frost and rain structurally. They'd be fine with a coat of render or wood cladding.

Christian.

[The Natural Philosopher]

Yep. My garage is built of those - rendered with Tyrolean finish (yuk)..but even just painted they can look remarkably OK. My choice would be a smoothish render finish painted, but thats just what we do in these parts..