The best roofing sealant

Hi all,

I've got an improvised metal edging on a pitched roof to stop the water ruuning down the wall. Edging needed because the roof is longer at the top than the bottom - the ridge is longer than the eaves.

The edging is 'L' shaped and slid underneath the slates. But the water is finding it's way around it with ease as the original sealant used isn't working.

What would be the best sealant to use? You can get quite a multitude of different products these days that seal in the wet, underwater etc. CT1 for example. But many of them are a ridiculous price as well £8 - £12.

Bitumen mastic out of the tube is what i'm thinking of using, only drawback being that it's nasty stuff to use.

Any suggestions?

Popular guy eh.

Well, for the benefit of anyone with a similar quandry:
I tried the bitumen mastic, but that stuff is seriously unpleasant to use, especially on smooth wet surfaces (couldn't find my blowtorch) you can basically forget about tooling it - it sticks to everything except what u want it to stick to. Not helped by the fact that i was working off a ladder, i decided to try the CT1 instead.

If u cover ur finger with plenty of saliva u can manipulate this stuff a bit, and even if it does stick to u eventually, it's not nearly as bad as the bitumen. That was between the L bracket and the slates - on top. Beneath (between the top of the wall and the underside of the bracket), i just pumped in as much silicone as i could.

It'll do the job 4 a while - i'll just have to keep an eye on it.

Maybe when it has to be redone i'll put on a timber fillet and cover it with 6inch wide strips of torch on felt, lapped from the bracket onto the slates, or something similar.

Still if anyone has anything useful to add about the sealants, i'd like to hear it.

Cheers

PS: given that i doubt there is very much adhesion between the CT1 and the metal bracket, you have to wonder whether a £1 tube of silicone (if you buy in bulk) might've done much the same job - to basically fill the gap so that most of the water runs on top of it down to the gutter. If there was any significant pressure on the water i'm sure it wouldn't take long to find it's way around the sealant.

Ah fellas! why didn't no-one say nothin?

Just dawned on me that i botched it. By filling between the bottom of the L bracket and the top of the wall with sealant, now if any water gets past the sealant on top (between the slates and bracket), it'll not be able to run down the outer face of the wall and so will run down the inside face instead (it's a solid wall), onto the ceiling and then it'll be raining plasterboard on the occupants!

Gutted.

Ah well, hopefully the sealant on top will do it's job for a year or 2 till i'm back up there again, then i'll pull the lower sealant out with long nose pliers or something.

As for all ur enquiries and replies - thank you - i'm busy at the mo - i'll try to get back to u as soon as possible