Screws to drill into lintle?

[Makhaira]

You need proper tech screws we use on site not retail stuff. Most cladding and roofing is fixed to steel frames like this it's nothing unusual.

https://www.google.co.uk/url?sa=t&s...PrTk8B2_GcxV3PTxg&sig2=esJWFrrIrYdRpm7szVqerQ

It's a bit sad, but discovering these made me happy.

 

[PhillyDee]

Tek lok screws are awesome, I use them extensively. Great for putting signage up, CCTV cameras into clad buildings etc. My favourite screw .

I would personally drill and tap the lintel as mentioned, I have all the gear anyway so wouldn't be an issue.