Hi,
I have a bathroom in a loft extension being constructed.
I have an external flank wall made of aerated blocks, I have 25mm battening fixed to this wall (@ 400 centres) with 25mm PIR insulation between the battens.
I will have a bath and shower against this wall, with the wall acting as part of the shower/bath wall.
It has been advised that where I use cement board against the PIR and battens I have 30-50mm air gap (battened out), as water can soak through the board to the other side.
I understand Hardie backer board will still allow moisture to soak through.
I will tile over the cement board.
Is there anyway to make the cement board 100% waterproof so that moisture cannot penetrate to the other side ?
And is it advisable to leave a gap at the ceiling and floor level for air to flow around the back of the board.
Must admit I have never heard such a weird arrangement - but makes sense, just wondered if their is a better way to put cement board up on a wall.
Thanks
I have a bathroom in a loft extension being constructed.
I have an external flank wall made of aerated blocks, I have 25mm battening fixed to this wall (@ 400 centres) with 25mm PIR insulation between the battens.
I will have a bath and shower against this wall, with the wall acting as part of the shower/bath wall.
It has been advised that where I use cement board against the PIR and battens I have 30-50mm air gap (battened out), as water can soak through the board to the other side.
I understand Hardie backer board will still allow moisture to soak through.
I will tile over the cement board.
Is there anyway to make the cement board 100% waterproof so that moisture cannot penetrate to the other side ?
And is it advisable to leave a gap at the ceiling and floor level for air to flow around the back of the board.
Must admit I have never heard such a weird arrangement - but makes sense, just wondered if their is a better way to put cement board up on a wall.
Thanks