Chalk on plaster

[goldielocks]

Can i use white chalk to highlight repaired areas on thistle multifinish plaster without it permanently marking or damaging walls in order to remind me where i patched? I intend to Gardz & emulsion later.

 

[JohnD]

If you want. You can rub off most of the chalk later with a dry duster, followed by a damp sponge.

I'd avoid coloured chalks as the dye might bleed through.

BTW most children's "chalks" sold now are actually composed of gypsum.

I don't think you'll need Gardz unless there is some other problem you haven't mentioned.

Just mist the bare plaster with emulsion paint thinned with water. A subsequent coat of white matt emulsion overall will equalise the colour and absorbency of the wall to reduce risk of patchiness in your finish coats.

 

[opps]

I just use pencils when I need an aide memoire to remind where to refill sections on walls.

I don't see chalk being a problem, you can wipe it off with a damp rag prior to painting.

How have you patched in the areas? If you filled with a better quality filler such as Toupret tx110, you do not need to use dilute emulsion, if you used something like Gyproc Easifill, it would be advisable to dilute the first coat of emulsion.

I don't understand why you plan to apply a coat of Gardz. As @JohnD says, if the plaster/filler is OK, just dilute the emulsion as per the manufacturer's advice (and not some numptie on the web who recommends adding 50% water).

I have been decorating for over 30 years. I have never needed to use Gardz. That said, if I remove wallpaper from a wall, I sand the whole wall to remove any traces of wallpaper paste.

Don't get me wrong, I have a lot of time for Zinsser products, but their advice to use Gardz to seal new plaster is bonkers given that dilute emulsion is absolutely fine.

 

[sparkwright]

Use those sticky coloured paper note things.