1 Jun 2011
Reaction score
United Kingdom
Hi, I've got some polycarbonate sheets that need sealing to the timber frames they are in. I had used silicone last year but the movement of the sheets has pulled it away slightly and now they leak. I have bought some Evo-Stik flashband to use and was just going to lay it over where the existing silicon is now.
Problem I have is that on the flashband packaging it says

"Flashband is bituminious and must not come into contact with Silicone Sealant"

Does anyone know why it says this and what happens if it does come into contact with silicone?
Sponsored Links
So what is the reaction? I didn't know there were different types. I used a strip of flashband last year in one section and it seems to be ok.
I have checked the download sheet for the black jack brand of flashing, as i had never heard of problems with silicone before either
it doesn't say anything on here about silicone.
Personally, I think you should be using proper lead not lead flashing, but flashband is loads easier to use, and definately better than just silicone!!!
Sponsored Links
NEUTRAL CURING SILICONE :idea: that`s what`s needed to adhere to most plastics - If it smells of vinegar out the tube - it`s wrong :cool:
Shame our buider hadn't seen this post, it might have prevented him using flashband with clear silicone sealant. His ignorance and lack of research means we now have a greenhouse roof that looks as if the flashband will, in time, provide a good damp course. It is rapidly melting where it is in contact with the silicone, and due to the builders incompetence he has had to use a lot of silicone so the glass dosent fall out. End result - a green house that is covered in black run off lines and a roof that, before long, will not be waterproof and £200 worth of glass covered in tar. :evil:

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local