On 30 Jul 2003 18:52:29 GMT, (Andrew
Gabriel) wrote:

In article ,
(Frank Z) writes:

Hi folks,
I need to plaster over a steel lintel over an open fore recess. Its
visible surface is 6" x 31" . It is 1/4" thick steel. The steel will
get fairly hot (I guess about the pemperature of boiling water but not
much more) because it is in close proximity to a fire. That means the
steel may expand and contract somewhat. I'll be using one-coat plaster
from B&Q, and the plaster will be about 6mm thick over the steel. What
is the best way to ensure the plaster stays stuck to the steel? One
idea I had is to rivet a piece of perforated sheet-metal to the steel
before applying the plaster. Any other suggestions would be
appreciated.

I think the plaster will crack big time if fixed to the lintel or
fixed to anything fixed to the lintel. I would look into having a
sheet of plasterboard fixed to the wall around the lintel, and
maybe loosly fixed to the lintel so sideways movement of the lintel
can occur, but you won't get plasterboard and plaster in 6mm depth,
so it would step out in front of the wall.

Maybe expanded metal lathing fixed to the wall around the lintel. Not
sure how easy it is to get some wide enough but in small quantities.
Like you say, movement of the steel could be a problem, but presumably
if it expanded that much, it would also crack the masonry around it.


--
John