paint cracking

[slowlygoingmad]

about 2 years ago i redid my kitchen and now the paints gone flaky and cracking off , the walls were skimmed with plaster and then i applied a coat of white emulsion before applying a top coat, ive noticed that the undercoat of emulsion has gone all chalky.whats went horribly wrong and how do i fix it ?

 

[TheDec]

Did you thin your first coat of emulsion prior to application? what do you mean by chalky and are your walls plaster skim.

Dec

 

[TheDec]

Yes they are plaster skim, missed that bit.

Dec

 

[joe-90]

Sounds like Eazi-fill on the walls.

 

[Robbie uk]

Did you use a contract matt? that is chalky to touch as it has no PVA in it.

 

[slowlygoingmad]

if i rub the paint under the flaked off top coat it leaves a chalky residue on my finger, as for the type of paint i used for the undercoat i cant really remember but it is the same as the ceilng which seems to be fine

 

[TheDec]

Kitchens are often subject to both high moisture and humidity, if any moisture has got behind your paint system it could reactivate salts thus causing the formation of Efflorescence. So try and determine. If this is the paint or the skim that is causing this to occur. Firstly you will need to scrape off and sand all loose and flaking paintwork and if this is just a paint problem apply one coat of an oil based primer sealer, If you think that there is an underlying cause apply one coat of an Alkali resisting Primer.

Dec

 

[slowlygoingmad]

i think the prob is a combination of using the wrong paint for the type of room and the skim as the flaking seems worse on the skimmed walls rather than the plaster board walls. i will rub of the flaky stuff and prime can you suggest a make of primer? will it be okay to use fastset to blend the painted surface to the sanded surface?, also for future reference is it ok to mist newly plastered rooms such as bathrooms and kitchens with normal matt emulsion prior to overcoating with a kitchen specific paint? also i read somewhere not to use vinyl matt for misting ,sorry for all the questions.im absalutely gutted as i may have made the same mistakes in other parts of the house but only time will tell.

 

[TheDec]

Dulux Trade Primer Sealer, I have not to my knowledge used the fast set yet I don't see there to be a problem. A mist coat should'nt really contain any Vinyl and you should use it to seal new plaster in all situations.

Dec

 

[slowlygoingmad]

once ive rubbed off the flaky stuff should i apply the primer sealer to the whole wall before redoing the top coat, or just the bits i take down to bare plaster, and if so does the primer sealer help prevent the rest going bad?

 

[TheDec]

It is never easy to establish what lurks beneath the surface of a paint system that has in anyway erroded, what paint system do you have eg Matt, Silk, or perhaps Eggshell.

Dec

 

[slowlygoingmad]

cant really be sure ,but i think the undercoat may have been crown vinyl matt (bq was selling it cheap) unfortuneately at the time i painted everywhere with it .the top coat in the kitchen was bq colour range (not even the kitchen stuff just normal). at the time i slapped it on the kitchen i didnt know not to use vinyl and i doubt wether i diluted it,i was really just using it to show up any imperfections after skimming some of the walls and plaster boarding others.MY nightmare is that ive used the same method on the house next door that i was doing up, only difference being ive used bq kitchen paint for the top coat . the house next door we inherited from the mother inlaw which flooded not long after she passed away, so ive had to replace all the ceilngs and do a few bits of plastering after all the work you can imagine the despair if its all been a waste of time, 2 years and counting

 

[TheDec]

I think your best bet would be to scrape what you can then sand it all down and then apply the sealer to the entire area.

Dec

 

[slowlygoingmad]

thought you might say that whats the best grit for getting the paint off? ive also just bought a big tub of dulux rich matt that i was going to mist the bedroom plaster board ceiling with ,would i be better taking it back and getting dulux trade supermatt as ive been reading that the rich matt might lead to problems wish i had came across this site sooner would of saved a lot of hassle

 

[joe-90]

mist it with a cheapo house brand.