If a roof said to be knackered it either means the roof covering is decayed so the solid covering be it slate tile zinc lead shingles whatever needs replacing repaired or the membrane underneath it being felt breathable membrane sarking or whatever needs replacing or the timbers steels are not doing their job.
Sealing a slate roof from the inside.
The slate must be clean before applying the sealer or you will seal any dirt and marks on to the slate.
Stick to conventional roofing repair systems ie a man a ladder and a tile slate.
Upon application it expands to fill every available space providing a superior seal that radically reduces roof leaks and shores up the overall structure of the rafters.
They claimed to make a roof watertight from the inside using a spray on foam i think it died a death in a very short time.
Roof leaks must be repaired from the outside to ensure the problem is corrected.
However when it is not practical to climb up on the roof to fix a leak such as during the winter months you can repair a leaky roof temporarily from the inside if you can determine where the leak is occuring from the underside of your roof.
Sometimes the water shows up at a ceiling spot distant from the leak.
If you have a conventional slate concrete or clay tile roof protherm can be applied from inside your loft space to your greatest advantage.
Some roof leaks are tough to locate.
My roofer has been replacing some slipped and fallen slate tiles on my victorian house as well as some repointing and fixing the ridge tiles.
Why are some roof leaks so hard to find.
Protherm is a process of roof repair and roof seal system designed to cure all your roofing issues plus provide a massive thermal insulation benefit.
Water tends to follow along roof rafters or roof decking.
Use the putty knife or your finger to spread the caulk around to cover the hole.
I agree with the above comment and if there were companies claiming otherwise i d run a mile.
The nail will provide a path for the water.
Make a temporary leak patch.
Use clean warm water without detergent as some can react with the sealer.
Insert a nail in the hole where water is leaking through the roof.
If your ceiling has a plastic vapor barrier between the drywall and the attic insulation push the insulation aside and look for flow stains on the plastic often water runs to openings in the vapor barrier such as at ceiling light fixtures.
Make sure that the slate is perfectly clean and dry before applying the sealant or this will cause streaks.
Use a putty knife to spread the tar into the leaking hole on the inside of your roof.
Use a caulking gun to apply caulk to seal any holes that appear in the roof.
However he now says the roof is original and the reason the tiles are slipping is because the nails are old and starting to fail nail fatigue.
Once you ve found the leak you can make a temporary leak patch from some plywood or shingle and some roofing tar.