How much firebrick is enough?

Joelemite · 06-17-2012, 08:51 PM

Hello all! Despite having zero masonry experience, I am building this outdoor alpine fireplace.

The "kit" comes with an insane amount of firebrick. I understand the importance of firebrick for insulation, safety, and thermal protection...but how far up the flue/chimney should you install firebrick? I assume that I only need to line the firebox, but I have about 450 leftover bricks. Is it imperative that you line all/most of the 10' chimney with firebrick? Any guidance would be appreciated.

jomama45 · 06-17-2012, 09:21 PM

Lining anything more than the firebox with firebrick seems ridiculous. Not sure what the chimney consists of, but if it's just simply dry-set landscape block, you'll probably need to line the interior of it as well.........

Canarywood1 · 06-18-2012, 11:39 AM

Quote:

Originally Posted by Joelemite

Hello all! Despite having zero masonry experience, I am building this outdoor alpine fireplace.

The "kit" comes with an insane amount of firebrick. I understand the importance of firebrick for insulation, safety, and thermal protection...but how far up the flue/chimney should you install firebrick? I assume that I only need to line the firebox, but I have about 450 leftover bricks. Is it imperative that you line all/most of the 10' chimney with firebrick? Any guidance would be appreciated.

In new construction they usually use clay tile for the liner,never heard of fire brick to line a chimney.

Joelemite · 06-19-2012, 12:23 AM

I think this is a situation of "common sense" vs. "but they shipped me a buttload of firebrick!" You guys are validating what I am thinking. Maybe the manufacturer assumed I would accidentally break 2/3 of the shipment. Thanks for letting me bounce this question off of the community.

Evstarr · 06-19-2012, 12:58 AM

Maybe they sent you 'municipal incinerator' instead of 'fireplace'. Bet the guy that got your order is pi$$ed!

Ps. 15,000 pounds! Wow! Maybe this IS 'incinerator'!

tony.g · 06-19-2012, 01:50 PM

In small domestic installations, fire brick is usually only used in the fireplace recess, not the chimney itself. The chimney is usually lined with hollow clay flue-liners built-in as the chimney is built - see sketch. A cheaper alternative is the old-fashioned method of 'pargeing', which is just smearing cement mortar on the inside of the brickwork as each course is laid. The purpose of lining the chimney is to stop smoke coming out of any of the joints in the brickwork. Sometimes, a vertical joint may not be properly filled with mortar and without a lining, smoke will come out. Perhaps not quite so important if the chimney is external rather than internal, but it wouldn't look well-built with puffs of smoke coming out here and there. But - 450 firebricks?!
Put them on ebay.