PDA

View Full Version : Portland cement plastering and a technical question.


Loose rivets
29th Aug 2013, 22:17
One finds oneself in a house in Clacton. It's been done out beautifully inside, but some less than sensible plaster has come off the front face of the house.

I'm trying to be as helpful as possible.

The facing 15mm rendering with pretty marbley bits in it, just fell off the top half. Not surprising, they'd coated the front on top of existing paintwork! The trouble is, some of it is sticking like blit to a shankit - as Dr Spooner might have said.

Given I've got to get the cosmetic rendering off, how the heck can I get several coats of modern paint of a (probably) 4:1 mix off the original rendering. It's a sizable house and I would think much of it is just covered in that darn Magnolia trade paint.

Some of it comes off in ribbons, but some refuses to do so. How the heck can the paint be cut back to the first plastering level? Does anyone have a house sandblasted?

gingernut
29th Aug 2013, 23:42
can you send a pic ? Sound s like a chisel may be your best friend.

G-CPTN
30th Aug 2013, 00:06
A pressure washer will remove the paint (if the appropriate jet pressure and distance is applied). You should be able to leave the original render intact unless it is badly adhered of course.

You could use sandblast, but it's worth trying with a power-washer first.

G-CPTN
30th Aug 2013, 00:10
ETQ2PXy9NCo

dubbleyew eight
30th Aug 2013, 04:22
depends entirely on what the paint chemistry is.
if it is a vinyl then a hot air gun will cause it to soften and then it can be scraped off.
if it is some hard enamel then a paint stripper may work.
there are two types of chemical paint stripper.
the older methylene chloride stuff evaporates fairly quickly so what you do to counter this is to do it in squares and tape alfoil over it until the paint softens enough to scrape off.
the newer paint strippers are gell containing ethylene glycol. the alfoil trick would work there too.

as others have suggested grit blasting may be the most effective way.

messy stuff though.