TheMick

Cheers Russ. I got the wire mesh you mentioned. Just got 100mm wide in case I can only get 50mm battens. Will cut it if I manage to source 25mm depth.

Mind bloody roof membranes are a bit of a mine field to find which is best aren't they. I'm guessing the higher the GSM the better?

Yeah but I can only get 50mm depth buddy hence the question about having a 100mm gap under the tin (2x50mm battens vertical and horizontal) )tah

Also just found out I can only seem to get 50mm thick treated timber for the battens from both local merchants. That would give me 100mm gap beneath the tin sheet of both vertical and horizontal batten on top. That acceptable you guys reckon? Thx

It's just that site is saying 25mm battens can split wothout you knowing i think. Is it best to keep the gap to 50mm or could 75mm or 100mm be OK. I suppose it increases the area for wind to go up so maybe a risk for lifting the roof off haha.

For the bug mesh could the first horizontal batten be at the bottom of the rafters instead of the 100mm or whatever up? Or is this not advisable for weather and such? I've done a bit of a digging and this site https://www.steelroofsheets.co.uk/supporting-roof-sheets/ suggest tek screws should not be used in any timber less than 50mm deep. With that in mind for the vertical and horizontal battens is it best to increase the space underneath the tin to 100mm or just use horizontal battens at 50mm directly into the rafters? Thanks for all your responses. They have all contributed to helping me push on with this. Cladco gear all ordered now and going to try and make it like the drawing by CPD but still unsure regarding infills and bug mesh at gutter end of roof.

So by draped do you mean just place off cuts of roof felt over the sky facing edge of the rafters where the screwed battens on top holding it in place? Thx

Thanks for that. The roof membrane if I have this right should be breathable to allow any moisture from the inside of the room to be released into the ventilated area beneath the corrugated tin. If the room ceiling was boarded out on the inside face of the rafters with insulation behind it wouldn't that mean there would be no warm air/moisture to release in this way?

But the cladco install video shows them going in the bottom near the gutter. It's doesn't mention fitting then at the top at all. Do you think it's better to just have the battens running lengthways or have a sheet covering the whole roof with the battens on top of it? Thx

It's like a detached garage with concrete floor and walls. It's always had a makeshift roof on which I've just been bodging each year or two. I want to get a better roof on then further down the line maybe board and insulate the walls, put a moisture barrier in possible board and insulate the ceiling etc etc

Hi visti, I understand what you say about the ventilation between the surface and the underside of the corrugated sheet but won't the ventilation be blocked by those wavy infill pieces cladco give you to put in the bottom of each sheet? Or will the ventilation just come from the peak of the roof under the ridge flashing you put on? Plus if screwed directly onto the sheet won't there be ventilation up every corrugation arch anyway? Thanks for all your replies. Just wanting it all clear in my head before attempting.

I'm on about having a ply or osb full sheet then corrugated roof screwed directly onto it instead of the perlins/battens suggested in the install, video.

So you think plywood or osb sheet is OK instead of battens/perlis too? Also when you screw in this roofing I notice the screw goes through the part of the corregated roof which is not touching the roof. The top of the arch if that makes sense. What stops the screw from over torqueing or is that not an issue as of the hardness of the tin?

Can anyone advise regarding the same corrugated roofing 13/3 please. First the widths of 990mm when lapped for one side of roof at 1.5mtr width - is there any reason why I can't have two sheets with a larger overlap in order to achieve the 1.5mtr width without the need to cut? Second question is it better to use perlins as instructed with lengths of timber or full OSB board thick enough to take the fixings screw lengths? Sorry if this is basic stuff but it's new to me. Thanks in advance.