Repairing external rendering

[john40]

I have a house built about 1930 of single brick that still has what I take to be the original render. There are hairline cracks that have let in water and caused damp on an internal wall.

I want to replace the render, which extends around a corner, to a total length of roughly 12ft by 4ft high. I have browsed the forums as to how this should be done but get more confused the more I read! There seem to be a dozen and more opinions about using, or not: pva - how much, when and in what dilution; the same applies to sand, cement and lime; galvanised or stainless steel for the corner? Can anyone supply a definitive answer?

I live in Worcester, so if there are any local experts who might want to take on and do an expert job - I'm 'listening'.

 

[ree]

Use SBR bonding agent for prepping the wall - do not use PVA on external or wet walls.

You can use plastic render beads - dont use galv.

Piecing in a patch, of the dimension you give, suggests that the whole render needs a careful examination.
Its useless patching in, applying a finish, and maybe painting, and then returning a year or two later for more repairs.

The mix will depend on a number of factors (eg. the existing finish), best decided on site.

Nowadays, external insulation is the way to go, but again, its all elevations to be done at once - not patched in.