waterproof building tape

[mopardave]

Ok gents (and ladies). I need some waterproofing tape to stick to a leaking external concrete stair case. It already has some on but it's old, splitting and generally naffed! Water is leaking through it now where the concrete meets the stone wall next to it, so it needs replacing ASAP. The stuff that's on is very thin, has moulded well to surface of the concrete/stone and appears to have done the job well......but it's now shot! I've searched online but I'm beggared if I can find any.
Any builders out there, can you help with a product name....tips for application etc?
Any help would be appreciated.
Cheers
Dave

 

[xpfloyd]

Dave, is there no way you can mastic the gap up? There's stuff called CT1 which can be applied in the damp and it's good at plugging gaps. Trying to visualise where you are using it but sounds like a flexible mastic of sorts would work better than a tape

 

[Jay]

Could you not ise flexible flashing tape

 

[Roadrunner]

You could try this stuff
https://www.amazon.co.uk/gp/product/B002HY2EJ2/ref=oh_aui_detailpage_o01_s00
100mm x 10m FlashBand Roof Flashing Roofing Flash Band Tape: Amazon.co.uk: DIY & Tools
I used it on a leaking flashing around our chimney seems to be working fine

 

[Jay]

You could try this stuff
https://www.amazon.co.uk/gp/product/B002HY2EJ2/ref=oh_aui_detailpage_o01_s00
100mm x 10m FlashBand Roof Flashing Roofing Flash Band Tape: Amazon.co.uk: DIY & Tools
I used it on a leaking flashing around our chimney seems to be working fine

Same as. I put some on a couple of broken slates 10 years ago as a temp fix. Still going strong..

 

[mopardave]

thanks gents.....great suggestions, all! I've just checked out the CT1.......I think in the first instance, this is the most appropriate stuff......injected straight into the crack. Then maybe some tape over the top.....biggest problem is where the stairs meet the wall. The tape that's on at the moment is very thin and has obviously had great adhesion but is breaking down now. I'll have a better idea what's going on when I remove this tape.
Thanks again gents!