Browse Forums Bathrooms and Laundry 1 Jan 27, 2021 8:24 pm Hi all, I'm renovating bathroom at the moment, tiling wet areas, but leaving other walls of the bathroom painted for that traditional look.. Our walls are full brick with render and has tile glue and other crap on it that needs to be stripped back. My question is after stripping, should I reapply it with white set plaster or acrylic render as my top coat for the bathroom (high moisture) before painting? I hear acrylic render is water resistant while white set plaster sucks in moisture (as told by my plasterer). Would it matter which render/hard plaster I use underneath as long as I apply a good coat of bathroom paint on top? Which of the 2 methods would give me the least problem on bubbling paint? Cheers! Re: white set plaster or acrylic render on bathroom painted 2Jan 27, 2021 8:53 pm Either acrylic render or regular cement render will yield a better result over time than white-setting. Biggest issue youd have is bond-breaking and drumming with white-set on render. Ive seen it fail countless times. Re: white set plaster or acrylic render on bathroom painted 3Jan 27, 2021 8:54 pm Standard white set is fine. Or better still is gypsum based set coat like thistle multifinish. It has the same smooth finish as white set without any of the issues. You don't need to use acrylic render. Just plaster, then paint appropriately. If you use white set then use an oil based sealer under coat. Accessible Carpentry & Cabinets accessiblecarpentry@gmail.com accessiblecarpentry.com.au https://www.facebook.com/pages/Accessible-Carpentry-Cabinets/583314911709039 Re: white set plaster or acrylic render on bathroom painted 5Jan 27, 2021 9:12 pm chippy Standard white set is fine. Or better still is gypsum based set coat like thistle multifinish. It has the same smooth finish as white set without any of the issues. You don't need to use acrylic render. Just plaster, then paint appropriately. If you use white set then use an oil based sealer under coat. Thanks chippy. What issues are you referring to with standard white setting? that gypsum based set coats don't have? Re: white set plaster or acrylic render on bathroom painted 6Jan 27, 2021 9:14 pm moudzj Either acrylic render or regular cement render will yield a better result over time than white-setting. Biggest issue youd have is bond-breaking and drumming with white-set on render. Ive seen it fail countless times. Thanks moudzj. so less with the paint bubbling, but more with drumming? Do you know how long the drumming and bond break appears with white set compare to renders? Re: white set plaster or acrylic render on bathroom painted 7Jan 27, 2021 9:19 pm Section 5 of AS/NZS 2311:2017 provides recommendations in regards to suitable paint systems for buildings. Table 5.1, which relates to paint systems for internal new unpainted surfaces, recommends that set plaster receives one coat of solvent-borne sealer or water- borne binder and two top coats. In WA most construction is double brick with white set. All painters recommend using solvent based sealer binders as the superior first step in the paint process. If you use Dulux use their "PRECISION sealer binder". Accessible Carpentry & Cabinets accessiblecarpentry@gmail.com accessiblecarpentry.com.au https://www.facebook.com/pages/Accessible-Carpentry-Cabinets/583314911709039 Re: white set plaster or acrylic render on bathroom painted 8Jan 27, 2021 9:21 pm Ask your plaster to float and then set with Gypsum. It's a much better finish and you will have no issues. The drumminess comes from the float not adhering to the bricks and not the final finish. Accessible Carpentry & Cabinets accessiblecarpentry@gmail.com accessiblecarpentry.com.au https://www.facebook.com/pages/Accessible-Carpentry-Cabinets/583314911709039 Re: white set plaster or acrylic render on bathroom painted 9Jan 27, 2021 9:38 pm We work very differently in moisture rich NSW. We avoid set-plaster like the plague, and it seems most painters here steer away from solvent based sealers and opt for a water based product - keeping in mind only acrylic paints (not latex) cannot bond to oil-based asu. Be careful. My old mans been a trade painter for his whole life, and owns and runs a fairly large company which does high-density resi work throughout Sydney. I grew up with paint. Also, Chippy; hes applying ontop of existing cement render. Re: white set plaster or acrylic render on bathroom painted 10Jan 27, 2021 9:50 pm To remove the existing tile adhesive he will remove much of the float. The Wall will have to be re floated before you skim it. You can't just skim over an uneven wall. And you can absolutely paint over solvent based sealer binder. It is done everyday, heck even Bunnings recommend using Dulux solvent based sealer on white set. Accessible Carpentry & Cabinets accessiblecarpentry@gmail.com accessiblecarpentry.com.au https://www.facebook.com/pages/Accessible-Carpentry-Cabinets/583314911709039 Re: white set plaster or acrylic render on bathroom painted 11Jan 27, 2021 10:03 pm Latex can be painted over solvent based, but not acrylics. Advice from the casuals at the big green shed shouldn't be taken so comfortably. Simon, see how you go with stripping the tiles and adhesive, you might be able to knock back the adhesive off of the existing render easily with a long handled floor scraper. Assess the situation then, and go from there. Re: white set plaster or acrylic render on bathroom painted 12Jan 27, 2021 10:09 pm chippy Ask your plaster to float and then set with Gypsum. It's a much better finish and you will have no issues. The drumminess comes from the float not adhering to the bricks and not the final finish. Trying to get myself up to speed with gypsum plaster with some online reading, many sites seems to suggest a disadvantage of gypsum plaster is it should not be used in high moisture places like bathrooms? Re: white set plaster or acrylic render on bathroom painted 13Jan 27, 2021 10:43 pm Your set coat is either lime based or gypsum based. Lime based products are more prone to failure because they rely on their mixing and application, there are more modes of failure. Much of that can be minimised by the use of a quality hard plasterer. Gypsum is simply add water and apply. It goes off quicker so again requires someone who knows what they are doing. The benefit of gypsum based set is that it is very hard (less likely to damage) and doesn't have some of the issues with painting that can happen with lime based set. No plaster product, plasterboard or hard plaster should be used where there is constant moisture. And you can paint acrylic paint over solvent based sealer binders. Go read the Dulux website. Accessible Carpentry & Cabinets accessiblecarpentry@gmail.com accessiblecarpentry.com.au https://www.facebook.com/pages/Accessible-Carpentry-Cabinets/583314911709039 Re: white set plaster or acrylic render on bathroom painted 14Jan 28, 2021 6:24 am chippy Your set coat is either lime based or gypsum based. Lime based products are more prone to failure because they rely on their mixing and application, there are more modes of failure. Much of that can be minimised by the use of a quality hard plasterer. Gypsum is simply add water and apply. It goes off quicker so again requires someone who knows what they are doing. The benefit of gypsum based set is that it is very hard (less likely to damage) and doesn't have some of the issues with painting that can happen with lime based set. No plaster product, plasterboard or hard plaster should be used where there is constant moisture. And you can paint acrylic paint over solvent based sealer binders. Go read the Dulux website. Thanks for answering all my trivial questions! Would you consider bathroom (daily shower routine) to be suitable for lime or gypsum white set? Is that what WA homes usually do for their bathroom painted walls (untiled areas)? Re: white set plaster or acrylic render on bathroom painted 15Jan 28, 2021 2:02 pm I have Gypsum set in my own house. The kids seem to hate using the extractor fan and at times I've walked into the bathroom to find water literally running down the walls. We have had zero problems. As I said no plaster regardless of it's type should be in a position that it is in a constantly moist situation. Basically if it is you have bigger problems. Just like plasterboard or standard white set, once it's painted it's sealed up and is good. With any hard plaster you need to let it thoroughly dry before painting. The gypsum tends to be more forgiving than the white set with regards to drying time. Accessible Carpentry & Cabinets accessiblecarpentry@gmail.com accessiblecarpentry.com.au https://www.facebook.com/pages/Accessible-Carpentry-Cabinets/583314911709039 Hi Alex, Thanks for the reply again. I had a chat with the builder, he said he will use primer, then hydrotec which comes with colour and sealer as well. A Renderer I… 12 18098 Suggestions please for acrylic rendering Color to match austral brick urban one pepper. Pic for reference. Thanks 0 5071 Thanks mate, is there a standard off the shelf type breathable product I can apply DIY? Thanks 2 8222 |