Re-Rendering.... Help!

[Robertspaw]

Hi

I've had a quote from someone to re-render the front of my house. At the moment we have a thin coat of roughcast. He has said that he'd take off all the cracked and flaky bits and would re-render on top of the remainder, with two coats of waterproof sand and cement.

He said that taking off all the roughcast might cause more problems and if it's sound it would form a good base, because its stippled.

Can anyone tell me whether it is ok to do this?

Thanks!

 

[Alastairreid]

Over the past few years we have been doing re-roofing and roughcast work for our local authority. it used to be the case that we would strip the render/ roughcast off using jack hammers,mash hammers and bolsters back to the bare brick.
that was up untill about 3 yrs ago when the local authority architects discovered the previously newly roughcasted houses were being troubled by dampness..............caused by choked cavities...........caused by the vibration of our power tools ripping off solid roughcast, delaminating the brickwork at the same time.

now the new specifications are to hack off all loose render, r/cast dub out, pressure wash stabalise, bead and scratch coat in readiness for 2nd coat and hit.

there is different products on the market now polymers. powerwall, mr epoxy resins, all requiring different procedures.

but not to be detracted from your question.......it is perfectly ok to leave the original render in place as long as it is sound and stable, and all the prep works are properly adhered to.

if retaining original render, and going straight over the top your contractor should also knock out all exterior brick vents and renew flush with new wall coverings.

hope this helps.