Fixing method for insulated Kingspan trapezoidal roof cladding

[solarcat]

Dear colleagues,

does anyone have experience fitting a PV system to an insulated Kingspan roof?

Would like to fix the system to the steel purlins below, however:
1 - how do I locate the purlins below the roof cladding and insulation
2 - which brand and type of racking can I use?

Thanks!

 

[solarcat]

The lack of replies to my questions suggests I am not the only one find this difficult at least..

 

[JD6400]

If you pm me your number i will let you know what we use and where to get it , there is to much to type so will tell you over the phone if you like ?

If it is around the 80mm thick cladding you are in look , literally just had a cock up on a kW system where this size fixing is now spare !

 

[whlphil]

You can fasten to the outer sheet alone using a Schletter fix 2000 bracket (I think its called), it sits over the rib 4 fixings in the side of the corru, this is the bracket that Kingspan Solar use themselves but beware if you fix to the sheet alone you will invalidate the warranty on the panel - bit of a rip off considering thats what they do themselves but hey ho.

Alternatively you could use a stand off bolt from someone like Ejot which needs to be fastened back to the purlin - dont forget the pull out calcs and structural frame calcs tho!

 

[flamefix]

K2 speed rail system

 

[whlphil]

K2 speed rail system

View attachment 8724

Be very careful with speedrail, K2 wont warrant it on material thicknesses below 0.63mm - Kingspan RW panel is 0.48 to 0.53mm on most panels and 0.38 to 0.42mm on some with an extra thin outer. The 0.63mm stems from the type of fastener that they use and its useful working range.

Also this again invalidates the warranty on the panel if its only fixed to the outer sheet!

 

[flamefix]

Yes correct not below 0.63mm at the moment but it is currently under test for 0.5mm. This image was on 0.7mm. Wasn't aware kingspan sheet was under 0.63mm apologies i'd focused on the trapezoidal.
Perhaps Tritec works to a thinner speck I think renusol might but not sure any of these have TüV approval.

 

[whlphil]

Yes correct not below 0.63mm at the moment but it is currently under test for 0.5mm. This image was on 0.7mm. Wasn't aware kingspan sheet was under 0.63mm apologies i'd focused on the trapezoidal.
Perhaps Tritec works to a thinner speck I think renusol might but not sure any of these have TüV approval.

The problem is with the fixing screws and the thread form of the screw, screws are designed for a specific material thickness range. The K2 uses an Ejot screw if I recall, theoretically you could use a different screw to achieve a better pull out which would work but K2 are reluctant to let you do that.

I think the Renusol uses an SFS screw which can do 0.48 so you could be right there!

One more word of caution even 0.7mm sheets are not 0.7mm they have a tolerance range and are generally always at the bottom end of tolerance (those lovely steel people can get more meterage for their tonnage that way) so a 0.7 sheet has 0.02 of coating which comes off the overall thickness as you are fixing to the steel not the coating thus the sheet tends to be in the 0.58 to 0.72 range so exercise caution as they are rarely at the top end of tolerance!