Newly painted exterior has yellow patches

[Harry Palmer]

I have just repainted the exterior walls of my house with Delux Weathershield. The walls are old but I brushed them down first as it's an old victorian house. I didn't prime or anything like that as they were already painted white, they just needed brightening up.

Within a few hours of painting I noticed a yellow colour coming through in places. What have I done wrong! and what can I do to fix it that won't cost me much as I'm on a tight budget.

Thanks loads

 

[gcol]

Have a look at this.
http://www.dalyspaint.com/surfactant_leaching.html

 

[Third_Eye]

What was the walls like prior to you painting them ? Was there any dirt, midew etc ! Also did the walls have an rough or smooth paint finish prior to you painting them ?

 

[gcol]

What was the walls like prior to you painting them ? Was there any dirt, midew etc ! Also did the walls have an rough or smooth paint finish prior to you painting them ?

What WERE, what WERE. Pronounce boy, prooooonounce!!!!!

 

[Third_Eye]

I admire you "gcol" cos u have waited patiently for you to get me back, well done, hehe. My english aint that great cos i am scottish. "nah wit a mean"

 

[Zampa]

Was there a chimney on this outside wall by any chance?..it could be soot migrating through, drawn by dampness..or maybe the wall has been coated with bitumen at some point..that bleeds through too

 

[gcol]

I admire you "gcol" cos u have waited patiently for you to get me back, well done, hehe. My english aint that great cos i am scottish. "nah wit a mean"

Get you back? What you going on about laddie?

Incidently, that would explain it - Scots do tend to speak/write like that. e.g. I done that yesterday.
Funny lot you Scots.

 

[Zampa]

Ever heard the Welsh?.."i'll be be with you now later"...

Brightness?..am I right?

 

[Third_Eye]

What was the walls like prior to you painting them ? Was there any dirt, midew etc ! Also did the walls have an rough or smooth paint finish prior to you painting them ?

What WERE, what WERE. Pronounce boy, prooooonounce!!!!!

Just pulling your leg "gcol" (from your spider, hehe) As they say in Dunfermline, "Ken wit a mean"

 

[Harry Palmer]

Thanks gcol - I looked at that site. It was quite damp when we painted. I tried scrubbing but the yellow bits were a bit like tiny bubbles and it pulled the paint off. I think I might have to repaint it and learn to libe with it.

The walls were already painted - just needed a top up. and no chimney.

 

[Zampa]

Try coating them with neat PVA first...allow to dry then re paint...if it is Bitumen staining the PVA should hold it back

 

[Third_Eye]

Did u use water or oil based masonry paint "Harry Palmer" ? Cos one of my neighbours got the cheapest qoute and the "painters" applied one coat of water based masonry paint over dirty walls etc (not visible at a glance). But since been painted the walls have turned many colours, though being white at first. The walls went yellow to green to grey to blue to yellow to orange are now turning dark grey streaks. Basicaly this happens when any contamination has been painted over. In other words it's all down to price, cos if a painter prices a job at £500 and another prices £3000 for the same job, then its obvious which one will get job. Also, to be honest exterior painting is all down to washing all surfaces prior to painting for the best job..........thats my rant over