Laminating a ridge board

[PeterW]

Question...

 

I need a 300 x 38 ridge board as we have 200 x 47 rafters cut at 50 degrees. 

 

Getting anything that size is problematic so my question is can I laminate / biscuit joint 150 x 38 lengths to make a ridge board at 300 depth ...?? 

 

I am thinking biscuits at 300 centre's and D4 along the joint with staggered joints between lengths. 

 

Thoughts..?

 

Edited June 22, 2017 by PeterW
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[Construction Channel]

cant see why not, you could probably get away with just winding a load of 250mm timberlocks through it but biscuits and glue would probably be better

[Crofter]

What about an engineered joist? Probably overkill but it would be nice and straight/level. You can get a 47x300 but not down to as narrow as 38mm.

[ProDave]

2 sheets of 18mm OSB glued and screwed together?

[PeterW]

Thought about a few of those options - OSB is one and even considered using 4x1 and 11mm OSB to create a laminated box beam. It's not structural so I'm not going to huge expense ..!

[Barney12]

3 hours ago, PeterW said:

Question...

 

I need a 300 x 38 ridge board as we have 200 x 47 rafters cut at 50 degrees. 

 

Getting anything that size is problematic so my question is can I laminate / biscuit joint 150 x 38 lengths to make a ridge board at 300 depth ...?? 

 

I am thinking biscuits at 300 centre's and D4 along the joint with staggered joints between lengths. 

 

Thoughts..?

 

 

I think I'd add some nail plates (spaced so they're between the rafters) too. For a sake of a couple of quid it's belt and braces.

[Russell griffiths]

If you laminated 3 layers instead of 2 you could stagger the joints more

 3 x12mm ply fully glued would be massively strong. 

Many different ways to achieve this all probably perfectly strong enough as you say it isn't carrying a load.