Woodfibre fixing schedule?

[Duncan62]

Hello all, my SE has washed their hands of the woodfibre and cladding fixing details. So I've come up with some myself, and would like a critique - or explain what you did for a similar build please?

 

Reading around, it looks like 45 degree fixings help to ensure there isn't any "sag" in the woodfibre/cladding due to the weight?

Stainless steel Screws for corrosion resistance?

 

Buildup:

300mm IBEAM (on 600mm centers)

18mm OSB

60mm Woodfibre

House Wrap/membrane

25x50mm vertical batten

45x45mm horizontal batten

Vertical thermowood cladding

 

 

Prelim Woodfibre Fixing Schedule:

 

 

 

 

Advice greatly appreciated!

[Iceverge]

That schedule looks fine although theres no need for the screws angled downwards I would say.

 

Do you have a plan to hit the studs through the membrane and woodfiber with screws? 

 

It might be worth getting someone to do the calcs on it as it looks almost over screwed. Every screw saved might be up to £1 inc your labour. 

 

 

[Duncan62]

38 minutes ago, Iceverge said:

That schedule looks fine although theres no need for the screws angled downwards I would say.

 

Do you have a plan to hit the studs through the membrane and woodfiber with screws? 

 

It might be worth getting someone to do the calcs on it as it looks almost over screwed. Every screw saved might be up to £1 inc your labour. 

 

 

 

Studs are 88mm wide. We have all the dims for stud location - so hoping that is sufficient to find them!

[Duncan62]

V2

 

[Duncan62]

Having searched - Fastener Types will be:

 

GREEN 8.0 x 140mm T40 Spax Extra Long Washer Head Wood Screw, Stainless Steel

RED / BLACK 8.0 x 180mm T40 Spax Extra Long Washer Head Wood Screw, Stainless Steel A2

 

[Mr Punter]

I don't understand the 45 deg angled screws.  With the washer head they won't even sit nicely.

[ADLIan]

Spax do similar in warm, pitched roofs. Rather than fixing being only in bending, due to vertical load, through thickness of the insulation it’s also part in tension. Makes perfect sense. Good fixings.

[Duncan62]

15 hours ago, Mr Punter said:

I don't understand the 45 deg angled screws.  With the washer head they won't even sit nicely.

 

 

Screws at 45 Deg will be behind the external closing so will not see them.

 

Screws at 45 Deg take the weight of the woodfibre from sagging/bending the horizontal fasteners.

 

I could change the 45deg ss flat head screw to a ss normal counter sink head instead.