Advice: Painting exterior walls

I was going to post this on a DIY forum but most threads don’t seem to get much of a response…much more likely to get some decent advice here 🙂

Need to repaint my house; 1900’s mid-terrace with rendered solid 9″ walls. (no cavity) The render appears to bridge the slate damp proof course, its only visible on the inside under the floors. No serious damp issues although the lower part of the walls tend to go a bit green. Current paint is something like Sandtex, applied quite thick.

I think (hope) the paint on the main elevations of the house is sound, but on the kitchen/bathroom extension to the rear (part brick and part breeze block rendered 9″ walls) the paint is starting to lift…the worst bits just peel off with a wallpaper stripping knife in relatively large bits. The old paint underneath is relatively sound but slightly powdery. Where new windows were fitted and new cement render used to repair the walls the paint is almost impossible to remove, so I’ll just try and sand these down to get rid of the texture and feather the edges to avoid them showing through the paint. I also have a doorway that was blocked up and rendered about 12 months ago that I never got around to painting.

Obviously I want the new paint to stick properly so it doesn’t need doing for a few years.

Any recommended paint brands?
Do I need to use a sealer or primer on the old paint and/or the bare render? Or use watered down paint as you would on fresh plaster?
I’m planning on brush or roller, there isn’t any huge benefit to messing about trying to spray it on is there?
Any other wall treatments I should consider over traditional paint? (bare in mind I need to keep a check on costs)

Thanks for any advice.

My house is 1890s, with similar slate DPC. It was bridged by the render, which was causing damp problems.

I chipped the render back to above the slate line, then rendered up to a bell cast bead. I left it as bare brick below my new render… damp problems disappeared. Painted the new render (and the rest of the wall) with textured masonry paint – I think it was Wickes stuff. Didn’t bother removing old paint, just gave it a good stiff brushing to remove any loose stuff and painted on top.

One year on it is all fine and dandy.

Dave

saw someone pressure washing their (exterior) walls prior to painting the other day – seems a slightly messy but effective way of removing loose paint.

Just use good quality masonary paint and be prepared to do two coats to get even coverage.

Personally, I’d use a brush but I hate the spray you get from rollers blowing over everything when painting outside.

oh, and when I paved down the side of the house, I filled the whole alley with compacted hardcore (MOT), but left a gap between the slabs and the wall and back filled it with pea shingle to make a sort of mini french drain.

HTH.

Dave

saw someone pressure washing their (exterior) walls prior to painting the other day – seems a slightly messy but effective way of removing loose paint.

Just had a quote for someone to paint the outside of my mums house [by the sea] – he’s included for jetwashing and painting with anti-fungal before two coats (of Dulux preferably he said).
He will not paint it without jetwashing first. I guess it also helps remove salt and other stuff that might stop the new paint sticking.

Thanks guys. So no primer required, just ensure walls are clean/washed and the paint should stick?

Yunki, I’m not very creative 🙁

I’m biased but I’d recommend dulux.

Even if you don’t use dulux the website is full of information and guides

http://www.dulux.co.uk/products/category_weathershield.jsp

Preparation is everything. Do it right and the coating will last. Do it wrong and it will be coming off in no time. You may need to seal the surface and do a fungicide/herbicide wash.

If the surface is rough and detailed (doors, pipes etc.) then I’d go for brush and roller. Unless you’ve sprayed before it can be really difficult to get a good finish. Much easier to over do it and have runs all over the place. Also you get a lot of overspray which means you need to be very thorough with your masking and covering. Also spray doesn’t “wet out” surfaces as well. With older coating being painted over brush is often recommended as you can work the paint in to the uneven surface.