Bostik Flashband Self Adhesive Flashing Tape for Roofs Grey - 100mm x 3.75m - Provides an Instant Watertight Seal - Complete With Primer

Works really well, plus comes with the added primer which is just about enough for each role, adding a little bit of water to the primer helps it spread over well. I'd definitely recommend using a heat gun with this, to get the adhesive backing / tar melting for it to stick well to surfaces and activate the adhesive, otherwise it will fall off, especially on cold days. Great product when you know how to use it well!

Perfect for what i needed it for.

Great product, sticks well and easy to cut. Difficult to manipulate into tight spaces and secure over uneven surface - but no fault of the product. Comes with small tins of PRIMER inside centre of roll - I missed that and so bought a tin of primer - which helped seal the surface prior to sticking down. Would buy again without hesitation.

The ceiling had been leaking upstairs for months. One day the plasterboard gave way to reveal a false ceiling and a previous collapse due to flood in the original plasterboard. Found a local roofer who accepted monthly payments, and he came round twice, once to inspect the roof and put up a temporary repair, and the second time to do a full one. The temporary repair lasted three downpours, which wasn't bad. He came round on the appointed day a week later and claimed to have replaced the entire first level of underfelt. It survived four downpours over the next week or so, and I began to repair the ceiling with spare plasterboard and filler. A week after the repair (but before painting, leaks appeared in the same area. He refused to even check his repair until I paid the second instalment. I told him to get lost, and he cancelled the contract having received one instalment. The neighbours had leaks of their own, and found a different roofer who let me use the scaffolding. I bought the tape in anticipation, and went onto the roof expecting to repair underfelt. I found a crack of about 8 inches in the lead wihich my roofer hadn't spotted despite him sweeping away years of moss from the gulley. I removed a few tiles to access the end of the crack, and discovered that my roofer hadn't replaced the underfelt as claimed. He simply placed a small piece of 'something' over where he had found a hole which he assumed was the source of the leak. The original underfelt is clearly showing. Anyway, I applied the primer which is supplied with the tape, and left it to dry. The fact that it was starting to drizzle makes no difference, as you apply the primer with a wet brush. I put lots of it in the crack and surrounding area. We then had a storm that included hailstones which lasted more than an hour. Not a drop of water came through the ceiling, and that was without the tape. Next morning, armed with heatgun, roller, sharp knife, I applied the tape to the repair. I heated a strip to facilitate the removal of the protective tape, and then placed it bitumen-side down over the crack. I used the heat to soften it further, all the time using the roller as advised. I put three pieces down as a belt and braces measure, knowing that the primer had already sealed the crack. This was done for extra weather protection. It has since rained gently once for about 10 hours, and there isn't a damp patch in the attic above. I also put some on some lead flashing against brickwork that didn't leak, and found that it welded to both surfaces. Time will tell, of course, but initial results lead me to recommend this product highly.

I used this to repair splits in our roofing felt. The first repair has lasted, but the second hasn't. I repeated the failed one and have had to secure a batten to hold it in place. My conclusion is they are sufficient for minor jobs, but the adhesive is not substantial enough for larger works.

What a great piece of kit - comes with its own primer too - perfect for a leaky roof and so easy to apply and cut to size - brilliant for the job :)

I used this to repair a damaged caravan roof that was letting in water. I opted for the 300mm width so as not to need too many overlaps - but I still overlapped a number of lengths without problems. I didn't need to use the primer - this seems to be mostly for porous, dusty surfaces such as brickwork. The flashing adhered well to the roof, and was easy to cut and apply. It's kept out the rain so far, time will tell how long it lasts for. The manufacture claims 15 years.

This stuff is great, fixed leak on felt roof perfectly. Repaired on a hot day so no heat gun required :-)

Did the job well.