Hair line crack


east yorkshire
Have discovered a hair line crack in a big six sheet on grain store.:(
What would folks recommend to seal it up for six or eight months or until I can get to replace the sheet
Many thanks


North east
I've had decent success from underneath with a tube of roof and gutter sealant on the crack. The cut a clear sheet to cover the crack and put plenty of stixall type stuff on to stick it to roof from underneath.
My neighbour uses flash band on the inside of the sheet and has sucess with it.
There is also the primer which gives a better bond.

The primer is essential IMO with flashband.

I have been very impressed with a glass reinforced sealant that sets pretty firm. Wire brush the sheet a bit around the crack, and then paint on the gloop. Everbuild Aquaseal. Sunlight and weather will degrade it after a few years though unless you get a good bond on the sheet, hence the wire brushing Wear a mask though... and gloves for the sealant application.

Bostik do a similiar non reinforced product called Flexacryl which is really great painted on asbestos or fibre cement hairline cracks. One coat is good, Two coats, and good for years.
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Brother has seen an aerosol on FB but can’t find it now
Sounds a bit witchy pee to me but anyone seen it?
The magical Flex Seal spray on liquid rubber? I think it's one of those things that sounds amazing but once you've bought it you realise it's something you rarely use. I would think it would work quite well for a temporary roof sheet repair though.

Cut one valley of a big six roof light and you might be able to slide it between the roof sheet and the purlins to shed the water onto the sheet below -assuming no fixing bolts in the way. All done from below from a cradle. Works for years.

I have more than one roof "mended" like that.... ;) Easier to use a thinner clear piece with 2-3 valleys.
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LIVE - DEFRA SFI Janet Hughes “ask me anything” 19:00-20:00 20th September (Today)

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Hello, I’m Janet Hughes. I’m the Programme Director for the Future Farming and Countryside Programme in Defra – the programme that’s phasing out the Common Agricultural Policy and introducing new schemes and services for farmers.

Today (20 September) between 7pm-8pm, I and some of my colleagues will be answering your questions about our work including the Sustainable Farming Incentive, Farming in Protected Landscapes, and our test and trials.

We’ll try to answer at least 15 of your top voted questions, so please vote on the questions you’d most like me to answer.

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