"DanG" wrote in message
news:_3mEf.84592$0G.14002@dukeread10...

You have me confused.

3x3x3/16 is light for lintel iron
Lintels carry the masonry load over openings.
In order to carry the load, the masonry rests on the lintel.
Where does this gap come in?

(top posted for your convenience)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Keep the whole world singing . . . .
DanG (remove the sevens)




This is for a kiva style fireplace. I'm building an arched opening into
the firebox so won't need the lintel there. The damper manufacturer shows
two places for a lintel. One is for the span across the opening. The
other is up near the top of the smoke chamber to support the flue liner.
Their recommendation is the 3x3x3/16". I will have brick on top of this
piece of steel as well as at the sides (ie. completely "embedded" in the
fireplace masonry). I don't want the mortar joints cracking down the road
due to expansion/contraction so was asking how much "air gap" around the
steel itself I should use to allow for the steel. Make sense?
Cheers,
cc