Dampcourse

[M.J.FULLER]

I have learn't just about everything I need to know about oven building from this site. One exception is that a dampcourse under brickwork has not been mentioned to my knowledge. I am building an oven at the moment and wonder if I should use dampcourse (a plastic membrane which stops water and salt rising up through brickwork). This is an issue for me for the concrete blocks and the stone cladding.

Any thoughts?

Michael

Woodcroft
South Australia

[Jed]

Originally Posted by M.J.FULLER

dampcourse (a plastic membrane which stops water and salt rising up through brickwork).

Are you installing this plastic just below the fire brick?

If it is just below the fire brick, I wouldn't think the plastic would tolerate the heat from the fire....

And any other place in the structure, I can't imagine where it would be a problem?

What is your concern,,, what is the source of the salt and water?

JED

[Neil2]

"dampcourse under brickwork "

I don't think this is necessary. None of the oven build I have seen on this site has that.

[dmun]

I've heard about dampcourses (aren't they supposed to be copper flashing?) in the Irish building video that came with my Bricky. The Irish seem to obsess about rising damp the way we pay attention to frost heave. I think unless your oven sits in constant wetness you shouldn't worry much about it.

I think it would be much more profitable to think about having well drained footings rather than try to fix the problem after the fact.

[brickie in oz]

It wont hurt to have a plastic membrane in the first or second course of brickwork if damp is a problem in your area.
Damp loves nothing more than brickwork, and as you have said it will carry any salts that are present along with it.

This is what happens long term to brickwork without dampcourse or flashing as its also called.

[M.J.FULLER]

Originally Posted by brickie in oz

It wont hurt to have a plastic membrane in the first or second course of brickwork if damp is a problem in your area.
Damp loves nothing more than brickwork, and as you have said it will carry any salts that are present along with it.

This is what happens long term to brickwork without dampcourse or flashing as its also called.

Thanks to all who replied. Brickie in OZ is onto the issue. It would appear that dampcourse is never used under the Besser blocks that support the hearth- why I'm not sure. My question is whether it should be used under the stonework that I am intending to have as an external wall. If you didn't use dampcourse under an external wall of a house in Australia you would experience saltdamp eventually.

Once again, thanks for the replies

Michael

[dmun]

That's a nifty wall - the Flemish bond, the angled setback, the "butter" joints - that no doubt would have been better with a flashing layer. Since it dates from the early Victorian era or before, with their lime mortar and soft common brick, it's a wonder it's held up as well as it has. Bricklaying utilizes a number of refinements, like flashing over arches and weep holes that we don't pay much attention to in oven building.