Now that you mention, when i was calculating the area to repaint, i recall those shaded area (further inside the car porch), the paint is perfect. Only those exposed (to sun and rain), have this problem. The paint used was Nippon Weatherbond, I am thinking the possibility of paint quality as well because less than 3 years already have this issue. Am considering to switch to Jotun Jotashield.

Tomorrow will try brushing it off and see if it comes off.

Thanks for the advice!

If the surface prep is good + with sealer, it will last long time. If there is still chalky fui sui, it doesn't let anything bond well to it, even the best paints.

If you guys have a jet spray i would recommend spraying the wall to clear of the old paint as much as you can until you see the bare plaster wall. This is only done on the outside, where rain and shine will 100% hit and exposed. Nippon or any other brand doesnt matter, as long as you buy Weathershield. I usually use Dulux/ICI paints. So far good.

Tried brushing off but doesn't help much, can see white powder / dust in the air, but the wall still looks white. Used jet spray (130 bar) also cannot remove the white stuff.

Will just jet spray the walls, paint a sealer, and repaint again. Hope this time it will last. I didn't use a sealer previously.

Need a higher bar maybe, im using 160 bar heavy duty jet spray. Because without that it sure wont come off and the job may look nice after finish, but it will wear out faster than advertised. Also use the same weathershield sealer and weathershield paint brand. I used to use Nippon sealer and ICI paint. hahaa. Not that it doesnt work, but better la, and buying all the same brands is easier also. I usually stick with Dulux/ICI.

Step 1: Jet spray and patch holes after. Make sure holes are nicely patched and no unevenness.
Step 2: Apply 1 coat of weathershield sealer, dont mix with water as stated on the paint pail, unless you have left it in the sun and it feels hard to paint then add just a little bit of water. Like less than 500ml.
Step 3: Apply 1 coat of weathershield paint first, wait for drying, dont need to paint 100% also nevermind. After 1 coat is done, if the weather is hot, paint a 2nd coat. Finish coats you need minimum 2 coats. Dont paint 1 coat, it will look ugly.

Sure it will last roughly about 5 years now, but also make sure you spray nicely la. XD Or else effort all gone. hahaha.. xD

Didn't realize jet spray plays a significant role. Definitely will spend more effort on this. Thanks!

No problem bro. Most of all is take your time and dont rush. DIY works usually you can take your own sweet time to finish it. So plan ahead and finish it when you are satisfied. Now rainy season also so need to get ready for rain sometimes.

Just saw your post and would like to share some information on this problem. This is efflorescent and is a very common problem in Malaysia, the root cause of this problem is actually moisture transferring the soluble salts from walls/plaster, seep out to the surface and crystalized to become the white solid. If there is no cracks on the wall surface for water to penetrate in, there are a few possible causes that may lead to this problem:

1. Improper painting system
2. Inferior sealer quality
3. High moisture level in the wall while painting
4. Direct contact to ground causing ground water to transfer to the wall

Now we know the root cause of the problem is the moisture inside the wall, assuming that the wall condition is still good, the best way to prevent it from happening is making sure the wall moisture content is always below 16% before painting. If the requirement in some circumstances are not able to achieve, base on my experience the solution would be by using strong alkaline resistance paint like this one, or any acrylic solvent-based wall sealer to replace the conventional water-based sealer. Alternatively you can also opt to apply a thick layer of acrylic based water proofing coating as sealer before subsequent painting if the wall moisture is constantly remain at the higher side.

Your solution should always be making sure the wall moisture level is low, and/or preventing the moisture from transferring the soluble salts out to the paint surface.

This post has been edited by PaintPals: Dec 27 2020, 06:22 PM

Hi PaintPals,

Thanks for sharing in detail. Other than the four reasons listed above, I can add cracks as one of the culprits to my wall's condition. I topped up my front gate pillars, and I can see crack lines forming already. I would have to research on filling those crack lines with proper water proofing materials.

One question, I presume you have a tool to measure the wall moisture content (to keep below 16%)? For us consumers who doesn't have the neccessary tool, how many days of hot spell to wait before it is safe to paint?

Almost done painting my house, with still a lot of leftover paint in the bucket. How long can it last? Few months? 1 year?

If you can close it tightly and store it in cool dry place avoiding sunlight, it will last you at least a year or likely more. Mine was last painted in Dec 2019. This past Monday I went to the basement to check on the Dulux Pearlglo paints to paint over some interior water damaged patches and there were all still good.

However if you store them in hot places they will be hardened and become useless.

If plastic tub would last long.
If metal tin the seal not good due to opening with screwdriver liao. Suggest pour out into plastic bottles. or cover with plastic/shrink wrap before putting lid on.

This post has been edited by ceo684: Dec 30 2020, 11:50 AM

It is called protimeter and ranging from basic to professional. You can invest in a basic one to check if there is suspect water leakage or any types of wall damage due to moisture. In normal condition that you washed the wall/reskim, just leave it for one day to paint it on the next day.

Anyone, can recommend me a paint? I want to paint my shop(interior walls). Old oredi colour fade out now. White paint enough. Clean look. Customers come in want to buy things also happy with my shop fresh look. Don't want super expensive paint with extra fancy features like easy clean anti fungus anti theft whatever . Something economical but won't stain(like whittish powder) if someone touch the wall.

If it helps, it's a grocery(well kinda) shop.

Another thing, suitable paint for exterior wall of a cold room? It's metal. Or just use same paint above(for shop's interior walls)?

This post has been edited by UnknownH: Jan 14 2021, 09:33 PM

Update to my case. Nippon sent someone over to inspect my walls, and it was due to cracks and ground water seepage causing the efflourescense. The guy used a protimeter to test my walls, and certain areas go up to 50+. As compared to my neighbour <20.

They recommend to jetspray then fix the crack via v-cut, followed by repainting. I asked the Nippon guy for painter contact and today a professional painter texted me with a quote of rm4.5k for an area of 40 meter square, including all materials. Jobscope includes:
Repairing the walls
1 coat flexiseal
1 coat sealer
2 top coat

Wow professional advice from Nippon

Glad to hear that you solved your wall problem, that is how a professional painting work is done.

Go for Satin finish Paint like Jotun Majestic Beauty Sheen or Nippon Satin Glo, that will give your shop a bright and fresh look, but on if your walls are skimmed to smooth finish. Otherwise just go with the conventional maxilite/matex range will do if budget is a concern to you.

Cheers. Always a concern but I don't mind paying extra if the paint hold well for a few years. Don't want to on budget and get something that will fade in 6 months.

Go for low-sheen/satin finish that provides good washability and premium finish (again provided that your wall surface is smooth). No worries on fading on interior paints, fading normally occurs due to organic pigments being degraded from UV. Normally in normal interior condition no issue for internal paint ya. Just go for reliable brands, some brands' economic range are powdery.