About 2 years ago I had the house repainted and asked for the same colours as the other houses on the estate

Thinking about touching up later I noted down the paints used

Having had some work done recently I got some of the paint, same code as the painters used

However it looks darker and I assume the painters added white

The question is anybody know what the ratio they probably uesd is

I believe it is a normal practice for Thais to add white

Cheers

They may have thinned down the mix too much & that will cause it to come up lighter. If you paint over an area with existing paint on it this will cause a darker look. If the paint is 6 months or more older it will have lighten. many variables. I try to buy extra tile & paint when I do a job . With paint also I have noticed when the automatic drip dispenser gives the pigments once in a while the will miss some of the color & that will result in change. Auto paint is even more critical 1 mg. of pigment less & your color is toast.

Yours probably is the age of paint & thinning it down. The white is usually in the base & should never be re added-unless you don't like the color & want to change it. It makes it a nightmare to match later. An old trick if your touching in paint is to do an entire side & try to blend the other walls.If it is a complete job chances are it was similar & just faded over the 2 years . That and if it wasn't dupont Duluxe weird things occur as they make some cheap charlie brands that pass themselves off to be the Jack & they are just Jack Shit.

Beardog is correct, even the best paint fades after time in this fierce tropical heat, my crack touch ups that face south are darker and do not match, the touch ups on the north side after two years are still a perfect match.

The common practice here is to add water as opposed to white. Something like 10% is ok for easier application, but when they go adding 50% it lowers the quality and makes it too light.