Painting new plaster woes

[paintedlady]

Hi there,

I was hoping someone could provide a bit of advice - I am currently painting my newly plastered bedroom walls and have run into a slight hiccup with the paint appearing a bit patchy in places. From the research I have done online I am figuring that this may be due to the plaster being 'polished' in places though I am unsure how to remedy this. Do I just keep on coating with paint, do I sand these areas down or do I apply a primer?

Here's some pics of the problem areas, hard to get a detailed pic because of the white but they are quite noticeable in person.

Ceiling - mist coats& 1 top coat 1

• paintedlady
• 15 Apr 2014
• 1

Ceiling - mist coats& 1 top coat 2

• paintedlady
• 15 Apr 2014
• 1

Ceiling - mist coats& 1 top coat 3

• paintedlady
• 15 Apr 2014
• 1

Ceiling - mist coats& 1 top coat 4

• paintedlady
• 15 Apr 2014
• 1

Window - mist coats

• paintedlady
• 15 Apr 2014
• 1

Further info: Plaster was left to dry for 10 weeks, dusted down and then 2 mist coats applied, using dulux trade supermatt. I applied one coat of the final colour to the ceilings before downing tools

Thanks for reading

 

[misterhelpful]

As you suggest, the pictures are not very clear but I can see the finish is patchy and uneven.

Are the patches where the first mist coat came away when applying the second or is that just the way it dried? If it did come away, you may need to sand back a little and fill with a fine surface filler before sanding, re-misting and finishing.

Overpolishing can be a problem and it is wise just to give those areas a very light sanding before applying the mist coat. Only experience can tell you what they look and feel like so, if you didn't know about it, it's not your fault. You can try lightly sanding the areas now to see if it helps when you apply the next coat.

Sometimes, new plaster can take a few coats to fully cover but one mist coat of Supermatt and two with the finish paint is usually good enough.

If you still have issues then you may need a coat of thinned oil based undercoat or Gardz to provide a better surface but that shouldn't usually be required for new plaster and would be a last resort. I think a little sanding and some more paint will get the problem areas covered.

Good luck.

 

[paintedlady]

Thanks so much for taking the time to reply. I'll have a go at sanding these areas and repainting within the next couple of days and see how I get on. Fingers crossed I don't make a total hash of it - I'll report back either way!

Its the first time I have ever had to paint newly plastered walls so at least I've learnt what to look for next time around

Many Thanks!

 

[joe-90]

Don't go sanding plaster wildly with rough sandpaper, you'll get a texture issue known as 'suede' that is a devil to recover from.

It's often easier to coat the dodgy areas with a decent primer using a brush and then re-roller.

 

[paintedlady]

Thank you, No I'll do it very lightly indeed. Is there a primer you would recommend? Someone had mentioned Zinsser, although they have quite a wide range to choose from.