Spray N Seal clear seal

Never used it but I thought products like this only sealed hair line openings?

peedee

True and i can see a few of these in the existing sealant especially around the front grab handles, might just give it a shot in a not so visible area and see what happens 

Tried something similar many years ago and it was absolutely useless. Ended up re-sealing the awning rails and grab handles myself using Sikaflex. Very messy job but easy enough with a good pair of ladders and lots of white spirit to clean the old stuff off

Thanks Keith, too cold to try just now, i did try a wee squirt on the gutter on the conservatory, and the results did not look too bad. I dont think i am at the point where the whole lot needs re-sealing as the damp levels are less than 25 pct in all areas. Will wait until the weather warms up and see what happens.  

I use Captain Tolley's. It's not a spray but a white liquid rubber that goes deep into cracks and crevasses then solidifies. It's dead easy and precise to apply so no wastage, It's made for boats really but it seems to work as several damp areas detected last year have been sorted. 

Being too cold tends to be the problem, old sealants go hard and contraction in the cold weather opens up the joints. Looks better in the heat as the expansion tends to close the gaps up again. In my case I found that trying to infill various cracks in the sealant was more hassle than doing the lot and of course doing the whole lot meant no future problems with sealants going hard for several years.

Not used this, but I didn't have much luck with a similar product.