Patchy paint appearance when priming recently skimmed walls

[goalc]

i'm just applying a primer coat to recently skimmed walls. Should the walls look patchy when the paint is on ? I know the idea is that it soaks in a bit, but i was expecting them to have an even finish.

I'm using a cheap emulsion for the primer from B&Q and have thinned it down by about 40% - is this too much water ? This is what the plasterer reccommended. The walls were skimmed about 6 days ago and appear to be completely dry.

Thanks...

 

[Third_Eye]

Every trade had different levels of insight and understanding. This is why everybody gives a slightly different advice etc. However you do not mention what type of primer coat you are using ! You need to explain what make you are using ! i.e. wether its matt, vinyl matt, vinyl silk, vinyl soft sheen or any other type of emulsion ? Als o you state you bought cheap B&Q emulsion and thinned down by 40% of water. This is to much thinning when using cheap emulsion. Though please reply what type of emulsion you are using please before i come to an conclusion ?

 

[goalc]

Hi Third-Eye

It is B&Q Value Matt white emulsion I am using. Both the plasterer and another decorator (who will be doing our big rooms) said to use a cheap one for the primer as long as I put a decent quality top coat on. I have now thinned it down to about 20% but am still getting the same effect. The bits that are dry dontlook too bad, but I dont know if the patchniess will show through once I put the top coat on (Once it is dried I will be using Dulux matt emulsion for my top coat)

Is 20% still too much water for this paint ? Will I need to go over what I have already done again before I put the top coat on ?

Also I have noticed that there is one patch in the middle of the wall about 3 inches by 5 inches that the paint is not reallt sticking to - it is almost as if it is on grease and wont go on - any idea what this is ?

thanks for your help...

 

[Third_Eye]

You will need to write down and reply on this forum the instructions that should be on the emulsion tub, before i can come to any conclusion.

 

[joe-90]

It depends on the plaster absorbancy. I prefer a few thinner coats to two thick ones - much smoother finish.


joe

 

[goalc]

You will need to write down and reply on this forum the instructions that should be on the emulsion tub, before i can come to any conclusion.

errrrr..... there aren't any instructions on the tub in relation to thinning it down !

 

[Zampa]

You will need to write down and reply on this forum the instructions that should be on the emulsion tub, before i can come to any conclusion.

errrrr..... there aren't any instructions on the tub in relation to thinning it down !

OK so we have established it REALLY cheap stuff then!

The mist coat (primer) will look patchy..in the sheen for two reasons..

One..you have applied it unevenly...the light bounces of different surfaces in different ways..just look at plain carpet tiles..they look like the have a chequered effect even though they are the same...thats because they have been placed against each other in different ways light is bouncing off them differently...

If you have a wall that has some areas that are quite textured due to not laying off properly with a roller and thers that are flat..then youl have a similar effect..

Same if you do them with a brush and overlap each section...the overlaps always look lighter because they are smoother..and have more paint on them..ever looked at the side of someones house after they have painted it with a brush and seen loads of squares???...now you know why..

Give the walls a good rub down with some 100 grade scratch and then put two coats of your decent paint over the top...one isnt enough as it will sink into the mist coat unevenly and give you more patches...the second coat will seal the surface...the thrid will finish it nice.

 

[goalc]

thanks Zampa....

looks like I will have a busy few days coming up !

 

[Growler]

Eh?
Your thinning paint down and then wondering why it's not covering.

 

[goalc]

Eh?
Your thinning paint down and then wondering why it's not covering.

yeah yeah....

if its painting and decorating you want, dont ask me..... if its IT Security on the other hand......

 

[Third_Eye]

NEVER buy paint that has no instructions cos if anything goes wrong then they aint responsible.

 

[confidentincompetent]

The first coats always patchy innit! Myself I dont bother with the cheap for primecoat malarky can't see the point/ bother of estimating how much cheeeeep paint i need to prime. Myself I feel The basecoat is most important coat so I always go for a decent brand. The shiny bits might be fat coming to surface just needs a light dulling with glasspaper.
yawn happy easter folks. nite

 

[Third_Eye]

Best emulsion to use over new plaster in my opinion is Dulux Supermatt. So try and buy this the next time "goalc"