Julian Cassell's DIY Blog

Choosing exterior paint is a task that shouldn’t be taken lightly, as not only are you making a decision from a decorative view point, but you’re also picking products that will actually protect your home. Paint really doesn’t like rain, and extreme weather conditions, so buying quality exterior paint that deals best with these issues will give you the most longlasting, and hardwearing finish. For instructions on application see my guides ‘Painting exterior masonry’ and ‘Painting exterior wood’, but for the moment, in this guide, I want to explain a little more about what you need from your paint when decorating the outside of your home, and which exterior paint I use and why.

Paint brands

Paint brands tend not to have several different ranges of exterior paint, which does make decision-making a little easier, as you are not hit with row upon row of options when you visit your local DIY outlet. Yes, you will find many manufacturers who say that their paint may be used inside and out, but I really would advise against using these as when dealing with exterior work, it stands to reason that a formulation made specifically for outside use will be harder wearing than a ‘multi-purpose’ interior/exterior option.

The two main players with exterior paint have always been Sandtex and Dulux. Farrow&Ball, Johnstone’s, Wickes etc. all produce exterior paints, but I would imagine that their market shares are far less than that of Sandtex and Dulux. There’s a good reason for this, as both Sandtex and Dulux have proven, long term, good track records in this area. Speak to most decorators, and you’ll find the majority choose one of these two, so it really is difficult to recommend any other paint brands ahead of these.

As far as my recommendations go, you’ll have absolutely no problems with either Sandtex or Dulux, but for me I’ve almost always used Dulux exterior paints, and because they’ve given me such excellent performance, I never feel the need to change. Therefore in the rest of this guide, I just want to talk about using the right system, and following instructions so you get the best performance out of the Dulux Weathershield Exterior Paint System.

Dulux Weathershield

Firstly, always opt for the Dulux Weathershield Trade paints – not the retail option that doesn’t have ‘Trade’ emblazoned on the side. Secondly, the system you use will depend on whether you are painting your masonry, you woodwork, or both.

Dulux Weathershield Masonry Paint

Dulux Weathershield smooth masonry paint is always my choice for exterior masonry. If there’s the slightest sign of algae on the surface, I’ll also use the fungicidal wash prior to painting.

I normally use the water-based masonry paint Weathershield system, although you can opt for the oil-based option (Dulux All Seasons) if you prefer – the latter will offer greater protection, but is not that user-friendly. I’ve generally found that the standard water-based paint is easily hardwearing enough, and so simple to apply, it is only in rare situations I’ve used the oil-based option – typically in areas of the country exposed to extreme weather conditions.

The standard system for the water-based Weathershield smooth masonry paint is two coats on previously painted masonry, whereas on new surfaces, you’ll need to first apply a slightly diluted first coat, followed by two further full coats for the best finish.

One further crucial consideration relates to older surfaces which show any sign of algal growth, as trust me, if you just paint straight over it, it’ll be back in no time. Therefore always use Dulux fungicidal wash prior to painting in these cases, following all the instructions regarding application. In this way, you then have a perfect surface for applying paint, giving it the best chance of lasting up to the 15 years specified on the tin.

The only other products you may need with masonry walls is an exterior grade filler to fill any cracks and holes, and in cases where wall surfaces are particularly dusty, you will need a stabilising solution. More about these in my exterior masonry painting guide.

Dulux Weathershield Gloss

Gloss is still the most popular finish for woodwork. You do have an option to use a water-based Weathershield system here, but I personally don’t recommend it as I still feel that outside wood definitely needs oil-based paint for the best protection. Before you get to applying this, good preparation is essential, but in terms of paint, you will need both Dulux Weathershield Undercoat, as well as Dulux Weathershield Gloss. On previously painted wood, one undercoat and one gloss is the minimum specification, with two undercoats and one gloss being my preferred system. Also, any bare wood requires priming before undercoating, so ideally use Weathershield preservative primer, however if you have another brand of primer in your shed that is recommended for exterior use, that will generally suffice.

Dulux Weathershield Guarantee

For smooth masonry paint, Dulux guarantee up to fifteen years, and for the wood system with oil-based gloss, they guarantee up to eight years – but you do need to follow instructions precisely. In reality, I have found that if you apply the masonry paint after good preparation, you get at least ten years. With woodwork, you should get at least four years, but believe me, you’ll get the full eight on windows in sheltered areas. The thing is, you will always get variation according to how ‘exposed’ the surface is – I have windows on my house that just require a wipe off after being painted seven years ago, and others that needed re-painting after five years. All you can do, is apply the Weathershield system correctly, and you will get the longest lasting finish possible.

Exterior Paint Prices

The problem with exterior paint is that it is generally more expensive than interior paints, or should I say the quality products are more expensive. But if there is any area of DIY decoration that screams out FALSE ECONOMY if you use cheap products, it’s exterior decorating. As mentioned above, you get up to fifteen years protection with Weathershield masonry paint, but with cheaper options you may literally only get a couple of years – really. So, if you do the maths, it’s much cheaper in the long run to spend more on a system that will last years, than one that will see you out on the ladder every year!

To find the best deals around, you tend to find that Dulux will often have promotions on their masonry paint especially, where big savings can be made. Look out for the 7.5 litre tubs shown in the photo above as they are regularly on offer at just over £20 a tub. Compare that to the normal £50ish for 10 litres, and you can see how big savings can be made. Although DIY outlets such as B&Q do sell Dulux Trade masonry paint, also keep an eye on builder’s merchant offers, as well as paint suppliers such as Dulux Decorator Centres. As always, white and magnolia will be the cheapest options – start choosing colours and prices tend to escalate!

Tags: buying guide, painting

This entry was posted on Sunday, May 12th, 2013 at 1:01 pm and is filed under Buying Guides, Decorating Tool and Material Reviews. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.