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Need to re-paint the outside of my house which has developed some small hairline cracks on the plaster. There are also a few larger cracks but no more than 2mm wide by 2mm deep which I have been advised to fill with clear silicon. Is this good advice? Also whats the best exterior paint for a building that winter time can be exposed to south westerly storms and driving rain on the coast?
cheers 🙂
my initial reaction is to recommend something like Dulux Weathershield... but while its been fine on most of the house there's some patches where the bricks are not protected by a DPC* and I think that a combination of this and a non-breathable exterior paint is aggravating the condition - encouraging damp penetration further into the building and accelerating frost damage to the bricks just below the paint surface.
If you dont suffer from any of these problems, then it is a very good paint indeed - stable and with good dense coverage.
Rather than use a silicone, use a decorators caulk (find an exterior spec one) as it is easier to paint over.
* 1890's quarryman cottage. In ye olden days lime mortars and lime plasters would have allowed the building to breath and dry much better than modern gypsum and cement based mortar even if without a DPC/DPM in the construction.
Stoner
By DPC I assume you mean damp proofing - interested you should say that as my house is approx 1840 so would be ineterested as to what breathable paint you went for.
cheers
I didnt. Hence the problem.
The paint job was done by a contractor a few years ago. The house had already been painted with a modern paint so there was little option but to apply a new coat.
If I had a choice I would never paint an old brick wall.
Dulux claim their weathershield is breathable, but IMO it can never be as breathable as no paint, or a lime wash.
As an exterior paint it is very good, I just think that in some conditions any paint can exacerbate a problem area.
Stoner, would be interested to see what you think this is? It's a white, hard resin-like substance. I think it could be efflorescence, as described here: http://www.sandtextrade.co.uk/ProblemSolver/Pages/Efflorescence.aspx
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efflorescence that Ive had has been more of a fine mineral crystal growth, rather than a resin. It usually occurs where moisture comng through the stone/brickwork transports mineral salts with it and then evaporates off.
Im afraid I dont know enough about it to comment on what's on your wall there.
Assuming that's a cement render though, id say that weathershield or somesuch will be fine on it.