Corrugated Metal Roofing

[Russell griffiths]

 

best pic I could find quickly. 

[ThomasD]

On 12/03/2019 at 15:58, Cpd said:

I spent a long time looking at velux installations in corrugated tin and NOT ONE was done well....... I looked at why they were done badly and then sat down and worked out how to do it well. I did the layout and install myself as the devil is in the detail if you want it all to line up and work properly. The most important aspect for me was the position of the windows and there size in relation to the corrugations in the tin sheets. You need to make sure that one sheets edge will end with with a non cut  downward sloping corrugations that falls directly into the inner gutter of the velux..... you then need to know that the windows width is also correct so that the far side gutter lines up with the next sheet of tin enabling that tin edge to fall in the opposite velux gutter...... then if you have multiple windows (I had 4 in my roof) you need to make sure that they all correspond with the corrugations.  There really is very little to play with on the set out as the tin does not allow for error, you get about 10-20mm of space in the flashing gutter to play with but you really want the tin edge  to fall in the middle as if it’s to close to the window it could block up with leaves or moss, to far and it’s not going to be as effective, also ANY error will be carried over to the next window as the corrugation spacing is set.  It’s possible with very carful layout but if this is done wrong your going to have another example of how not to do it.......  if you find a contractor that says they can do it INSIST to be able to go and look at one of there installs..... I visited 3 different installations done by 3 different professional roofers and I would not have payed for the work...... 

Thank for you this post, it’s very useful indeed. 

[Bramco]

On 12/03/2019 at 12:32, Tom's Barn said:

My issue is finding a contractor that has fitted corrugated metal roofing including velux lights.

 

@Tom's Barn   Did you ever find a contractor?

 

On 18/05/2019 at 22:54, Visti said:

We're about a month from installing our and also struggling to find competent contractors for both the corrugation and windows together.

 

@Visti  Did you ever find a contractor

 

 

Anyone else who has installed corrugated roofing and cladding - can you recommend any contractors?

 

Simon

[Tom's Barn]

On 27/07/2021 at 13:24, Bramco said:

 

@Tom's Barn   Did you ever find a contractor?

 

 

@Visti  Did you ever find a contractor

 

 

Anyone else who has installed corrugated roofing and cladding - can you recommend any contractors?

 

Simon

Unfortunately, the only contractor I could find was in Scotland and he was not willing to travel. I had 4 local specialist contractors visit site, all had experience of fitting corrugated metal roofing, and unfortunately, not one of them could articulate exactly how he was going achieve two things: 1. water tightness around velux. 2. insect seal the end of the roof panels whilst still providing ventilation. One contractor actually suggested that he would fit the roof and then told me to find a velux specialist to fit the roof lights afterwards.

 

On the basis that I could not find any contractor that provided convincing installtion details I resorted to standing seam. Not what I wanted but it does look good.

 

I hope that helps

 

 

[Bramco]

Thanks Tom,

 

I'm hoping I've tracked down a couple by looking through magazines, web trawls etc.  One is very local, the other by the welsh border I think although they say they have often worked across this way.

 

Just waiting for the quotes to come in  - fingers crossed....   I'll try to remember to report here if we can actually get things done.

 

Simon

[saveasteading]

Fixing anything through profiled metal, to be weatherproof and attractive is very difficult. A roofer who thinks it is not would worry me. 

Even if worked out precisely it can be different in reality as cladding widths vary +/- about 10mm, and lines wobble. 

For a skylight in a house I think I would create a box-out first (timber and lead) to get a foolproof and tidy transition. 

This is only theory, as I know lots about metal roofs and not so much about houses.

These good examples above are very impressive, but still grounds for a little concern in storm conditions. 

For anyone who does not know, every metal profile has foam fillers available. Tidy closures, but seagulls peck them. 

[Bramco]

31 minutes ago, saveasteading said:

Tidy closures, but seagulls peck them.

 

Not in south Notts they don't.  Haven't seen one in months - and then only flying over....

 

?

 

Simon

 

PS Actually, thinking about it, that's a lie. I did see a seagull sat on a street light - a la seaside - but in the next village. It looked quite lost!

[Cpd]

Insect mesh goes between the lower batten and top batten, foam filler goes between top batten and profiled tin. 
I live in a very severe weather location on the west coast of Scotland  70Mph + winds directly hitting the building and no problems with the velux installation yet. 
but as others have said, if you cannot find an installer that can’t answer  basic installation questions then it’s time to look for a new installer or at some other roof covering. 

[mac the knife]

Have someone installing a corrugated roof and now comes the hard bit, with velux windows to be installed.  
after explaining numerous times that only a nibbler could be used to do the cutting he went at it with a circular grinder and a 'special disc' he got. 

 

anyway, this is the end product. We had a disagreement. He complained about the quality of the cladding numerous times even though it is widely used on houses and domestic buildings. Anyway, he left taking all tools with him
Any pointers or suggestions would be welcome

We can move that sheet one rise to the right as we were going for a double overlap 

 

These are long continuous sheets. How do I get the flashing in under the sheet

 

[jamieled]

This might not help you, but the only way I've seem this done (and how we did ours) is to stop the sheets at the side of the velux making sure the sheet drains properly into the side velux gutter. Then sheet above and below the velux, lapped appropriately and new sheet started on the other side of the velux.

 

See @Cpd's Post above.

 

I can't see how you can make your example watertight without having at least one cut sheet.

[mac the knife]

thanks.

I removed photo as I think the roofer frequents this forum

[saveasteading]

can you pm me the photo ?

[Cpd]

And me…..

[Russell griffiths]

All the houses near me with metal roofs and roof lights have series of sheets cut to different sizes flashing around the window. 

[mac the knife]

1 hour ago, Russell griffiths said:

All the houses near me with metal roofs and roof lights have series of sheets cut to different sizes flashing around the window. 

explain that to me please

sheets cut above and below the window? or sheets cut and only running down as far as the end of the roof window frame on either side, leaving the full bottom flashing showing

or another solution

thanks

[saveasteading]

I did a pm to mac because of the sensitivity, but not a lot of use really wjthout the full context.

 

It is always a complex jigsaw of lapping and underlapping, while ensuring that the corrugations don't  get in the way of flow, yet allow a seal.

Perhaps easiest to cut all the touching sheets to length top and bottom. This may require additional battens. There is then less to think about, less to go wrong and less twisting of resisting elements.

 

Cladding can be overclad, as long as it is sealed at every joint and is taken to the next flashing, eg ridge.

 

Order plenty of spare sheets when there are openings, as even superb cladders make mistakes on openings..and there aren't many of them around.

[markc]

+1 to the above.

trying to fit corrugated around Velux or other box protrusions is very difficult aesthetically and mechanically.

fit the protrusion to suit the corrugated sheets as half corrugations are a pain to seal and never look right.

[Russell griffiths]

The roofs by me are standing seam so maybe not going to help. 

They have laid a flat sheet acros the top of the window for the full width, the sheets above come down and finish on this flat sheet. 

The width of the side sheets has been altered as well, so probably like you having a larger overlap on your corrugated sheets.  

[John regan]

I’m installing metal corrugated roof sheeting with velux roof windows. Would it be possible to let me know what type of flashing you used to seal around windows. If you have any pictures of stages of installation this would be much appreciated. Thanking you, John.

[iaaeap]

Hi All,

 

I've read this thread with interest, in particular the bits about using counter battens to ventilate below a metal profile roof covering.  I'm going to be doing this on a log cabin which has tongue and groove roof boards, but I'm using Cladco roof sheets rather than what the manufacturer offers, so I am trying to sort the detail myself.  Cladco do not have details for installation with counter battens.  I plan to install it something like the image below (not at all to scale, sorry).  

 

What I can't quite figure out is 1) how to finish the breathable membrane at the gutter end, 2) whether to have the metal sheet extend beyond the battens/wind board to prevent water running onto the battens, and 3) whether to/how to vent the ridge.

 

On the first point, should I use some sort of strip nailed to the T&G to lap the membrane onto, so that what you see is a neat strip hanging into the gutter rather than a flap of membrane?  Any suggestions for a product for this?

 

On the second point, the counter battens and battens will be 25mm, raising the base of the roof covering 50 mm from the T&G, and owing to the 12.2 degree roof pitch also moving the lower edge of the roof covering 10mm out from the upper edge of the wind board, on which the gutter will be mounted.   I'm slightly concerned that with the roof covering being at least 50 mm above the gutter and already being 10mm beyond the edge of the gutter, water is at risk of passing over the gutter, particularly if I extend the covering to prevent water running onto the battens.  Any thoughts on this greatly received.  I guess that if I move the lowest batten up slightly, and extend the roof covering say 10 mm beyond the line of the wind board, then the battens are safe, but am I still going to overshoot the gutter during heavy rain?  Maybe that's something I have to live with?  

 

On the last point, I've seen reference to having the eaves open for ventilation (which I'll do) but to seal the ridge flashingto prevent wind driven rain.  How is the roof ventilated if the ridge is sealed like this?  Also, do people tend to leave a gap at the top of the roof sheets - or butt them up to each other?

 

Any thoughts very gratefully received.

 

Thank you.

 

Edited November 15, 2022 by iaaeap

[joe90]

I used cladco sheets on my workshop roof, I didn’t use counter battens but draped the felt between rafters to create drainage/ventilation. The felt was run over the ridge to create a water roof layer in case wind driven rain got under the ridge capping. The lowest batten was 100mm from the sheet edge to not make it not vulnerable to wet from the rain entering the gutter. My felt was run just into the gutter but I guess you could use felt trays for a more robust solution.