Water-based whites will yellow as well if the prep didn't effectively seal the tannins from coming through. The only way to prevent yellowing is to use a paint without oil and, if using water-borne/based paint in a light color to absolutely ensure that priming is done properly in order to prevent all tannin bleed.
So, a Class A sealer has the least likely chance of yellowing because Class A sealers conforming to C1315 are required to have the least yellowing characteristics however both types and all classes can and will yellow in most cases over time if not properly formulated - beyond the performance requirements of C1315.
One of the most effective protective measures for white exterior walls is the application of a weatherproof coating. Given the often unpredictable and harsh UK weather, weatherproof coatings act as a barrier against external elements, protecting your paint and the wall underneath.
Changing Colours
So again, two coats is an absolute rule. If it's crazy drastic (i.e. you're going from black to white, or eve white to yellow for example) you might need three. There really is nothing worse than the old colour finding itself through, so be thorough.
Over an existing finish: Apply two coats of Stain Blocker, then 1-2 coats of Brushable White Enamel, White Poly (spray only), or Milk Paint. Always let any primer dry overnight. Many primers suggest a 3-hour dry time and that is not enough.
Johnstone's Trade Professional Gloss Brilliant White
Despite being oil based, which can result in yellowing, this professional gloss paint has an anti-yellowing formula which makes it our top contender!
Using Primer for Enhanced Coverage
A good primer can make a huge difference in the coverage of white paint. Primer helps create a uniform base and can block out previous colors and stains. It also improves the paint's adhesion, making it easier to achieve a solid, even finish.
The most common cause of this phenomenon is exposure to sunlight, which can cause certain types of paint to oxidise and change colour over time. Additionally, environmental factors such as excessive moisture, high temperatures, and cigarette smoke can also contribute to this yellowing process.
Clean marks off white walls with washing-up liquid
Using warm water, make a cloth damp but not wet, then add a dot of washing up liquid, and gently wipe the mark. Dry the spot immediately with a clean, dry cloth to avoid water marks. If the stain doesn't disappear, then wait five minutes and try again.
Polycrylic, on the other hand, leaves a clear, non-yellowing surface, so it won't change the appearance of lighter woods such as maple or birch, or anything painted white.
Mod Podge can turn slightly yellow over time, especially when exposed to sunlight or UV light. To prevent yellowing, store your Mod Podge projects away from direct sunlight.
Acrylic paints do not tend to yellow as much as solvent-based paints, and are the only sure way to protect against premature yellowing.
I just grabbed a spray bottle and did a 1 part white vinegar to 10 part water mixture. While the polycrylic was just a little tacky (mostly dry) I sprayed it lightly with the mixture and wiped it down with a clean clothe. It took the yellow right off and it has never returned.
After Sunlight and UV Rays, Humidity and temperature swings are two environmental elements that can cause kitchen cabinets to yellow. High humidity and temperature fluctuations can wear away the protective covering of the cabinets, revealing the underlying material and giving it a yellowish color.
Regular Cleaning
Gently washing the walls will remove dust and grime that can accumulate and dull the bright white finish. A mild, non-abrasive cleaner and a soft brush are all that's needed to keep your white masonry paint looking new. Remember to rinse thoroughly after cleaning to avoid any residue.
Note: Although Advance yellows less than conventional alkyds, a slight amount of yellowing may occur. This effect is accelerated in dark or poorly ventilated areas and is more visible in lighter colors. WARNING! If you scrape, sand, or remove old paint, you may release lead dust.
Based off our rule of thumb, two coats of paint is the absolute minimum you'll want for your walls. However, the material and previous colour of the wall can both influence this number – for unfinished drywall, for example, you'll want to add a coat of primer or undercoat paint too.
Clean Regularly
A soft cloth should do the trick, but if you need a deeper clean you can use a mild cleanser or soap and water mixture on the wall. Be sure to test the cleanser first in an inconspicuous spot to make sure it won't degrade the paint—the last thing you want is a bigger problem on your hands.
Favorite whites for ceilings include White Dove OC-17, Cloud White OC-130 and Decorator's White OC-149.
"Dulux Quick Dry Satinwood creates a mid-sheen satin finish, providing a subtle, attractive alternative to gloss. It is self-undercoating, wipeable, non-yellowing and suitable for use on interior wood and metal.
It almost looks like a true off-white; however, it does have a touch of yellow undertone. SW Pure White looks muted and much warmer than SW White Snow.
If your white painted wall is exposed to light most of the time, it is likely to stay beautiful and white. The parts hidden behind the furniture are likely to suffer from the yellow tinge of chromophores.