Advice on leaking corrugated roof!

rubs

Hi all, moved into a new house over the summer and realised there was a leak in the roof of a rather large garden shed with a corrugated galvanised sheathed roof.

It turns out that the previous chap fixed the galvanised nails in the trough as opposed to the peak of the sheathing, i.e slap bang where the water runs down...!!

Any suggestions for a product I could use to seal around the nails?... Tried silicone and bitumen tape but no joy...

Cheers in advance,

paddy147

rubs wrote: »

Hi all, moved into a new house over the summer and realised there was a leak in the roof of a rather large garden shed with a corrugated galvanised sheathed roof.

It turns out that the previous chap fixed the galvanised nails in the trough as opposed to the peak of the sheathing, i.e slap bang where the water runs down...!!

Any suggestions for a product I could use to seal around the nails?... Tried silicone and bitumen tape but no joy...

Cheers in advance,

Tech 7 or else Rito Waterstop.

Both are brilliant and work underwater too.:)

martin46585

If it is a typical garden shed with only a few sheets on each size, then maybe try replacing the nails with tech screws which can be screwed down tight on the rubber washers,

deandean

From my experience of the exact same problem you're never going to get those holes water tight.

Best attempt is patches of denso tape 50 x 50mm over the tops of the nails & making a seal with the sheeting all around.

reilig

Put short corraugated sheets over the leaks and nail it in the peaks.

wayoutwest

IF the length of the sheets are the same at both ends [they should be if shed is square]I would strip sheets off, then turn them over so the troughs become the ridges. A 4" angle grinder can easily take the heads of your nails as they are quite lightweight.Then,the shanks,that are left sticking out of the roof batons can be bent and broken of with hammer or grinded off.

red sean

wayoutwest wrote: »

IF the length of the sheets are the same at both ends [they should be if shed is square]I would strip sheets off, then turn them over so the troughs become the ridges. A 4" angle grinder can easily take the heads of your nails as they are quite lightweight.Then,the shanks,that are left sticking out of the roof batons can be bent and broken of with hammer or grinded off.

Brilliant. That's using your head!

martin46585

Whilst turning the sheets would solve your nail holes, it would also turn the joints inside out. On new corrugated sheeting, it is rolled with "upper" edges or"downers" the latter being the norm, and if reversed they would all be facing up.
Even on older stock length galvanised sheets the lap will be inside out, which could be more of a problem than the nail hole,

And maybe if there is a decent lap it will be fine......

wayoutwest

Sorry martin46585, but I'm not getting what you are saying. What are 'downers' and 'upper edges'. Tin sheeting should have an overlap of two ridges and ,ideally, laid so that the 'joints' are facing away from prevailing wind direction.

martin46585

the edges on the outside of most sheets face down, see below where as if you were putting on space sheet on a agri shed the edges would face up, as to not allow rain to drip in.
if you were to turn the sheete up side down, the underlap would become the overlap and would be more open on the outside,
but if the sheet have more than the single over lap, then it might suit ok....

wayoutwest

As long as you have an overlap of two ridges....or two troughs- it should hold out against any wind driven rain.