Mounting to corrugated 'cement' barn roof?

[willabovebeyond]

Hi

We are currently looking at an install on a barn roof that has corrugated 'cement' sheeting on it and we are wondering what is the best way to mount to it, and how many fixing points are required?

We want 2 rows of 8 landscape panels. Here is an image of the roof.
The spacing between the wooden beams is ~1200mm



What method of mounting would you suggest? Hanger bolts with vertical rails?

PS. We will check if the roof has some asbestos in, so please don't focus on that.

Any info would be much appreciated.

Will

 

[SolarCity]

I'd be amazed if the roof didn't have asbestos, but don't let it stop you if does have.

I'd go for hanger bolts directly into the timber. A pretty straightforward install. For God sake make sure you use crawling boards.

 

[telectrix]

looks like asbestos to me.

 

[Worcester]

Schletter with vertical rails and landscape panels. Accessories | | 1 | Schletter GmbH And look at the corrugated roof fastening kit(s) - also check this video SchletterInc's Channel - YouTube and SchletterInc's Channel - YouTube and SchletterInc's Channel - YouTube (they are 3 different videos)


The panels could be fibre cement we have come across quite a few on cow and sheep sheds and grain stores. If you haven't got a certificate from the owner, get it tested.

 

[JD6400]

You can normally get a idea from the year when the sheets went on as to what they are likely to be , but they look like fibre to me from the picture that is ?
If you are on wooden purlins in our experience it is absolutely imperative that you go for hanger bolts , so that you can take out the undulation of the purlins , the roof may look flat but when you start putting any decent sized systems of a reasonable length up there the difference will stand out a mile !
We always cross rail on wood as well.
And even with crawling boards , we would not touch it without net's.
You only need to drop a proverbial and go through once and it does sharpen you up to why they were there !!!!!

 

[Worcester]

My roofers have a great motto, "You only fall off a roof once".

 

[jupestar]

Just digging around looking for something which might help.

Has anyone done an installation on concrete purlins, the type with the lip for the j bolts to hook onto?.

I'm thinking j bolts, with a rubber washers in the hole, them a large metal washer/spacer above to spread any movement and protect the asbestos. then the plate then the rail. It;s not exactly off the shelf and doubt you will find it in any PV manual. But i've done a test and it is as solid as a rock.

What have other people used..

 

[Earthstore]

One other thing, you will need to have a structural survey on the roof and it will fail.
The timbers used are unclassified, so a structural engineer has no specifications from which to make their calculations, they need to be at least C16 timbers.
If the barn is pre 2000 it may well have asbestos, after that it should be OK.
And yes, make sure you get the inside netted, when I was young I fell through a roof, fortunately it was only a shed, so I am still here..
If you fall through, believe me, it happens quickly..

 

[whlphil]

Ive been a commercial roofer for 20 years, you cant tell by looking at a panel wether it has asbestos in it or not, unless your lucky enough to find the Eternit ones where they are stamped or sprayed with identification on the side lap. Get it tested - i know some unscrupulous people who were selling old asbestos sheets even after 2000!

You need to net the underside or work from harnesses clipped to a running line on the walk board (only harness if over 4m from the floor as harness is no good under 4m - you'll hit the floor before it stops you ) if you dont and you have an accident or the HSE turn up first then good explaining your way out of jail - they are not very receptive to people trying to flout the law or plead innocent to not knowing the rules as you should be competent to carry out the works.

Your right about c16 timber, proving it will be almost impossible, if your going to go ahead then just hope MCS dont decide to come checking!

Concrete purlins is a difficult one ive fixed steel angles to the sides before with tapcons then used standoff bolts from the angle (cant do that on prestressed purlins), your way doesnt sound too bad, you want a Dowty washer on the top side of the roof, you could chock the gap between the purlin and the underside of the sheet with timber but thats a pain, just dont apply any weight to the roof sheet as it will crack.

Final point make sure you tell the client your not responsible for any leaks or damage to the roof post install as its virtually impossible to work on a asbestos/fibre roof without damaging it.

 

[JD6400]

Just digging around looking for something which might help.

Has anyone done an installation on concrete purlins, the type with the lip for the j bolts to hook onto?.

I'm thinking j bolts, with a rubber washers in the hole, them a large metal washer/spacer above to spread any movement and protect the asbestos. then the plate then the rail. It;s not exactly off the shelf and doubt you will find it in any PV manual. But I've done a test and it is as solid as a rock.

What have other people used..

I can tell you for a fact it will fail on the structural calculations , well i have happily not found a engineer bent enough to put his name to one yet !
The best way to do it is to come off / around the rafters with a site fabricated bracket then through the sheet with large stud and fix your rails to that , you will need a beefed up cross rail but one advantage is you do not need to matrix the fixing rails as you will now be able to come through where you need them !
You can get it all from Regent Green Engineering just ask for Alan (Bloody top bloke). I know he on holiday this week though !
He may even come out and measure up the brackets for you .
Or you could offer to re sheet the roof and install zed purlins alongside the old concrete ones , the zeds are slightly larger so it essentially make the concrete ones obsolete .

 

[Coleman]

Walk away mate, if that isn't asbestos I'll be amazed! Sorry to be blunt

 

[jupestar]

Just go a DNO approval through, was kind of hoping they would hold it for a few more weeks to be honest but there you go...

does anyone know a company which will take on a roof installation on and asbestos roof? - they would need to cover health and safety. I've done them but only small scale, was looking forward to doing it to be honest, but the DNO approval has only just come through and i don;t have the time to do and organise myself, i need an experienced roofing team to come in and do it.

If anyone knows any experienced teams let me know. It is 20KWp...

 

[powervan]

nothing like a BARN to get all senior members excited!! timbers look like load be a prob!! but HAY u cud always get the cows to MOOOOVE to another if roof falls in

 

[Earthstore]

Before an install there is still lots of work to do, as mentioned it needs Asbestos testing and then organize a company to do the drilling if Asbestos is present.
And this Structural survey, which 99% certain it will fail, so then you will need to upgrade the roof, and scaffold and netting.
Have a look at the DNO, does it say "valid for 30 days?"
Also do you have planing?
I have a 35KWP system being installed on a 4 year old barn as we speak, with all the procedures that we had to put in place, all 100% above board, it took 4 months from initial contact to install date.
I do not think it is possible for an install before the 12th, only my opinion.
Just out of interest, where in the country is this barn?

 

[jupestar]

Earthstore - just to reassure you we are covering everything and it won't take 4 months.

It is asbestos - hence i'm looking for asbestos experienced team. It has passed a structural survey, due to the immense steel structure it is sitting on. No he doesn't have planning and no he doesn't give a ****, he's put the app in and he's happy with that!!!

Yes it needs nets, scaffolding i need advice on. but this only takes a couple of days to sort out. Basically i get a roofing team to install and ideally be responsible for safety everything else is in hand.

 

[powervan]

who is clearing the cow pats up we may mess about on here but i would hope we all HAVE PRIDE in the work we do BUT we DEFO dont want no come backs so we may approach it from diff angles but hopefully cover all aspects of the job correctly and if UNSURE this is the place to confirm!!

 

[Earthstore]

Oh dear, I was trying to be constructive.
So all you really have at the moment is DNO approval.. Hmmm
How did it pass structural, more importantly who passed the structural? If you read an earlier post, written by a experienced roofer, he also confirms it would fail structural, I except there is an "immense steel structure" however they are not C16 timbers.

May I wish you all the luck in the world with this install, And I hope nobody gets injured, and the customer has a system that will work for 25 years.

 

[powervan]

in other words PULL OUT NOW!!!

 

[jupestar]

sorry there has been some confusion between my post and the original post. there are no timbers involved. "jobs a goodennn" signed of my structure, and a 50 years experienced roofer.

 

[powervan]

50yrs!!!!! u mean a thatcher) lol well hope it is a good install with loads of profit!!!!!!!!!!!!!!!!

 

[Cider]

https://www.electriciansforums.net/attachments/a9-pdf.120235/

It isnt rocket science, just common sence.

 

[Earthstore]

I really have tried to help, but I give up on this one !
When a photo clearly shows timber purlins and then we are told no timber is involved, well I despair...
We all have to start somewhere, but trying to install on a barn before the 12th, without even knowing what mounting system to use is, well, words fail me!

 

[Worcester]

Properly managed installations are easy to do before the 12th.

We are starting on a simlar roof, (that has been checked structurally and is OK) from initial contact with client to completion, including DNO approval for 50kwp will be less than 4 weeks. (Oh and yes we have got all the panels, mounts and inverters in that time). - we start on site Monday, it will be finished by Friday including all saftey precautions.
But then I'm not an electrician, I'm a civil engineer with extensive construction project management experience. - We have another 50 kWp job we started Tuesday, it will be complete by Friday night once again fully compliant with all the regs. We are getting DNO approval for 50kWp jobs in less than 15 days. - Maybe it;s the way we talk to them

 

[whlphil]

How on earth did you get planning in that time?

 

[powervan]

WORCESTER is my SUPER HERO not just a mere electrician!! got to be the SENIOR of all SENIOR members