How do I repair a corrugated flat roof?

[Udhi]

Hi all,
I have a pre fab garage (a rare watertight one!) with what could be an asbestos currugated roof on it. There is a single ling panel of clear plastic roofing actung as a fixed light.

The asbestos/cementitious stuff is fine but the plastic has broken up to let water in.

I want this plastic piece replaced without messing with the rest of the roof.

Can this be done? Are all corrugated roof panels made with the same width and height of corrugations??! Obviously the plastic panel matching the cementy one is a good indicator but does it hold true so many years later?

House is in North West London if that helps?

Many Thanks

 

[dilalio]

This should do it...
http://www.wickes.co.uk/Wickes-PVCu-Clear-Corrugated-Sheet-660x2400mm/p/240152

Just make sure that it overlaps surrounding area and that the valleys and peaks of overlap "nest" so that rain can't penetrate.
You could seal the edges with sikaflex EBT for good measure. You might need some new fixings too if old ones are rusted up... Give them a good spray with lubricant before heading down to Wickes - 15% off everything this Easter!

 

[Udhi]

Thank you. So the size of the peaks and troughs is standard on all wavey rooves?

 

[alan333]

IIRC there's old imperial sizes and new metric sizes, and IIRC they're not totally compatible, but they're close so you can sometimes get away with changing one - but not several in a row cos the profile runs a few mm out - so by the time you have two sheets in a row the end of the second sheet is over an inch out. I'm a bit out of date but 'big 6' is the bigger of the two common imperial sizes, I can't remember the smaller one.
Measure your sheet size, and measure the distance between 'peaks' (or 'troughs'). Better to measure as many peaks as you can and divide back to get an average.

 

[Udhi]

Ok thank you. I had a feeling it might be standardised but when I do some internet shopping, there did not seem to be any dimensions given for these peaks and troughs. Good thing I asked!!