Ridge tile pointing repair

[Steve]

Hi. I've been adjusting the TV aerial on the roof. The roof ridge has a row of half round tiles; the tiles are separated by about1 inch with mortar in between.

I've noticed there are small gaps, around a millimetre, at the edges of some tiles - the mortar has separated from the tile edges. They may have been like this for some time or it might be because I disturbed the tiles (walking/sitting on them).

The morter between the tles is in good condition and very hard to break. I tried chipping away as I was thinking about cutting it back enouigh to try pointing, but it is really tough.

Should I do anything about 1mm gaps? If so, is there a good way to fill them without cutting back the existing mortar?

Thanks.

[Dave Plowman (News)]

Cement mortar is a poor material for ridge tiles - as the roof always moves relative to them. And the stronger you make it the worse the problem. Use a good non setting mastic to fill any gaps. If doing again use lime mortar.

[Steve]

.

Thank Dave. Can you suggest a source for non setting mastic? I can't see any on Screwfix or Toolstation.

[NT]

[e-mail]...> >

I wasnt sure whether to mention bitumen

NT

[Steve]

After some research on mastics, I've decided to use some stuff called Aquafix. Soundss right for the job. e.g.

and be easy to use as its applied with an applicator gun.