dpc around windows prior to rendering

[kieranfinn]

HI ALL.
About to start rendering new build and have noticed dpc as been cut back flush with block work.plasterer as assured me this is the norm but someone as said the dpc should have been worked into the render.
If this is true any ideas on rectifing the damage done or do i believe the plasterer.

 

[Micilin]

HI ALL.
About to start rendering new build and have noticed dpc as been cut back flush with block work.plasterer as assured me this is the norm but someone as said the dpc should have been worked into the render.
If this is true any ideas on rectifing the damage done or do i believe the plasterer.

Hi, how did you get on with the lentils?.

Going back to basics - have you seen his work and spoken to clients?

If they are happy and he has done a nice job, the tradesman is usually fine.

I personally scratch into the dpc and cut it off but it depends on how teh dpc and windows and cavity are - he may be quite right in what he is saying. Do you have pic?

 

[kieranfinn]

scudding went ok .large house with many windows(lintels)but got price down a little.have seen his work for inside plastering very good was also a large house,not seen his outside work but i would have thought good inside good outside.just a bit worried about this dpc now.no pic sorry.

 

[Micilin]

Sorry - Do you mean the dpc at bellcast level, or a dpc into windows and doors (sometimes windows are set back rather than forward of the cavity) or over lintels?

 

[kieranfinn]

Sorry - Do you mean the dpc at bellcast level, or a dpc into windows and doors (sometimes windows are set back rather than forward of the cavity) or over lintels?

dpc down side of window ,window set back so dpc was then trimmed straight down flush with blockwork.

 

[Micilin]

There is no gap between the frame and wall ? ie when he renders will render bleed in behind frame? You can seal this up with mastic (or foam if large) now if done neatly so it does not get in the way of render. If using foam spray frame with wd40 to stop it sticking, but being careful is a must.

I can't see the render bridging the cavity, but just in case is there any of the cavity exposed on the outside of the windows?

 

[kieranfinn]

There is no gap between the frame and wall ? ie when he renders will render bleed in behind frame? You can seal this up with mastic (or foam if large) now if done neatly so it does not get in the way of render. If using foam spray frame with wd40 to stop it sticking, but being careful is a must.

I can't see the render bridging the cavity, but just in case is there any of the cavity exposed on the outside of the windows?

its hard to explain all i know is when blockwork for windows are built up you have dpc sticking out around frame work wedged with a polystyrene strip holding dpc, now windows are in dpc as been trimmed back is this ok .hope you understand my explanation.thanks for persisting any way.

 

[roughcaster]

HI ALL.
About to start rendering new build and have noticed dpc as been cut back flush with block work.plasterer as assured me this is the norm but

someone has said the dpc should have been worked into the render.

I "wouldn't" do that, but I have seen it before. The way it was done, was to fold the strip (1"or so) of excess dpc over onto the window/door reveal blockwork. The reveals were then scratched, with the folded/tacked dpc within the scratch coat. Disaster,,,, the rendered reveals cracked vertically, about an inch away from the frame, because of the unstable nature of the dpc underneath/within the render. I don't see the point of it. It would have been better to trim it off, rather than do it that way.

I would scratch/render, right up to the dpc against the window/door frame, and then cut off any excess. In your case, to make amends for the excess that's been cut off, you might be able to squeeze in a small strip of dpc or similar, around the windows etc before rendering, and then trim that off after the reveals are rendered. All rendered window/door reveals are normally finished off with a bead of suitably coloured sealant anyway.