Hello,
I haven’t tried this myself, but Dulux, Simply Refresh (one coat paint) has a convincing video that shows a dark colour being painted over a lighter colour and covering it with one coat!
As it’s a Dulux product, it’s worth a try. The worst that can happen is the wall needs another coat and you complain to Dulux. I would like to see it demonstrated the other way round.
I.e. A lighter colour covering a darker colour in one coat!! Yes that would be worth two exclamation marks.
Speaking of number of coats; read this from Dulux concerning exterior painting:
Know that less is more: While priming the surface to be painted is a good idea, when it comes to paint, never overdo it. There’s a limit to the number of coats a surface can support. As paint ages and thickens over time, it loses its flexibility and ability to expand and contract, causing premature cracking or flaking. For long-lasting results, apply a maximum of two even coats of paint to achieve the desired colour appearance and surface protection. Never paint wood when it is wet as the new paint will rapidly blister and flake off.
The physics of it seems to make sense.
Yet, surveyors often specify 2 undercoats and 1 gloss coat.
Or, 1 undercoat and 2 gloss coats.
Or even 2 undercoats and 2 gloss coats.
So what’s it going to be?
Whatever the number of coats, it is not as important as the preparation.
Besides, if the surface is rubbed back with a modern, get-into-all-the-grooves power tool- like the Mirka, there will be less microns of paint thickness for the surface to support.
As Dulux says above “There’s a limit to the number of coats a surface can support.”
We normally quote for 1 undercoat and 1 gloss coat. This is the usual specification and enables the client to compare like with like.
Plus, of course an appropriate primer to any bare wood or substrate.
All that, of course, after thorough preparation.
Painting outside in early summer is such a pleasure after a wet cold winter and I am looking forward to it.
Please contact me for a free quote and sound advice.
Good luck
Joe