On Sun, 20 Jun 2004 13:23:57 +0100, "stuart noble"
wrote:

Sounds like you have lousy sills which you should ideally replace

Thanks for the input Stuart. Timescale is my problem for replacing them
- see my reply above.

(particularly if they don't have a drip groove on the underside).

They do have drip grooves.

If you prefer to modify the existing, you need to get a flat surface,
preferably sloping away a fraction.

The 'concrete' they are made of does seem to be fairly soft, and no
obvious concrete-type gravel visible at the surface. I did wonder if I
might be able to grind them down in-situ to get a decent run-off slope.
We had our limestone frontage restored last year and the stonemasons
used an air chisel to rough it back and a stone rasp to smooth it. I
wonder if I might achieve similar on these sills with my small SDS
chisel and/or an angle grinder if its not too hard. Don't know where to
get hold of a stone rasp though.

Polyfilla Exterior filler is fairly easy
to use as a skim although I would use car body filler if you can face the
extra work.

By 'extra work' do you mean sanding it smooth after it has gone off? I
had the impression that Polyfilla Exterior was not particularly durable
or perhaps I'm biased by the interior stuff.

Then you need to get something genuinely waterproof on there.

I'm not clear why you suggest both a skim and a waterproof paint.

Pliolite paint is good but any solvent based paint will be better than
conventional masonry paint, which is not at all waterproof IME.

That was my other question (see my reply above), so thanks - I will
avoid conventional masonry paint. I'm not familiar with Pliolite though
- what is it? By 'any solvent based paint' is that as in ordinary gloss
woodwork paint?

Phil
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