Chimney corbeling / slope

[leen...]

Hi All,

As part of my brick BBQ, I need to construct the chimney which needs to slope in front, back and both sides. I was originally going to construct this bit out of metal and clad with cement board but looking at the measurements again, I think I could corbel (I think that is the right phrase for stepping the bricks to make a slope?) the front / back as it isn't that far to cover (around 160mm front and 260mm back). I could them cut these to form the slope of the sides. Couple of questions

1. Any issues with that plan?
2. Looking online it looks like I position the bricks 1/3 (33mm) of the way over the row below so for 160mm I would need around 5 rows and for 260 -> 8 rows. So assume I would do the front ones at around 20mm to give the 160 over 8 rows like the back?
3. For the inside, I will now have a stepping. Is this ok for the smoke or do I need to render/ cover in cement board?
4. I would like a flat finish outside so assume I can render that ok?
5. I have seen examples of laying the bricks with the length pointing 90 degrees towards the middle of the chimney (as opposed to running on top of the wall below)

Thanks in advance for all your help and advice.

Lee.

[The Natural Philosopher]

5 it seems

Nope. Its just a brick chimney after all.

Do whatever makes the thing work out.

Its fine. The only critical thing is that the aperture - the hole in the front of a fireplace - is not more than 3 times the cross sectional area of the chimney- at least to start with.

Yes.

Bully for you.

[leen...]

Thanks for your reply. One thing I forgot to ask was whether I need to change the mortar mix. I have been using 1 cement to 5 sand for the other block work.