View Single Post
  #6   Report Post  
Posted to uk.d-i-y
Dave Plowman (News) Dave Plowman (News) is offline
external usenet poster
 
Posts: 43,017
Default Is angle iron adequate for lintel?

In article
,
mike wrote:
Does anyone know if a 3.5 inch angle iron over a 12 foot span is
adequate to support 8 foot of brick wall above?


A 12 foot wide picture window was replaced in a cavity gable wall,
with the result that the outer skin of the wall started to collapse.
There's a lintel on the inner wall but the outer wall was just built
off the original frame.


The collapsed part of the wall was taken down, the angle iron
installed (I didn't see it installed but I'm calculating it's 3.5
inches as it's not the full width of the brick but the outer edge is
visible), and the brickwork rebuilt.


It wasn't inspected by BCO.


To me it looks like there's a noticeable bow in the middle.


I can see why angle iron would be used so as not to disturb the inner
skin, but it seems quite a long span, and that some sort of U-shaped
construction on its side that would allow two or three courses of
bricks to be built within the U would be required. How is the weight
of the roof factored in?


Is there a table or calculator online that deals with this? And
should it be BCO inspected?


Angle iron IMHO is pretty useless for this sort of thing - to make it
rigid enough would require far more material - ie iron - than a better
shape. Traditionally this would be an H section as in an RSJ. Or a box
section if fabricated. Or, of course a pre-stressed concrete lintel.

I guess what the BCO will say - get in a structural engineer to do the
proper calcs.

--
*If a mute swears, does his mother wash his hands with soap?

Dave Plowman London SW
To e-mail, change noise into sound.