Purlins - where to have the join?

[MarkH]

The main bit of our house is just under 11m long and therefore the purlins (200x100mm green oak) aren't going to be single lengths as 11m+ oak isn't easy to come by. So given I'll be using a couple of lengths where should I scarf them together? Close to one of the four trusses? In the middle? 

[Stones]

One for your SE to specify I think?

[MarkH]

I've emailed him, just thought I'd ask here anyway - just making eye-contact with the SE costs £65... His drawings only mentioned the purlin size, not the location of any joints.

[PeterW]

41 minutes ago, MarkH said:

 The main bit of our house is just under 11m long and therefore the purlins (200x100mm green oak) aren't going to be single lengths as 11m+ oak isn't easy to come by. So given I'll be using a couple of lengths where should I scarf them together? Close to one of the four trusses? In the middle? 

 

It will have to be over a truss but the SE would need to specify the joint scarf / method if it is structural join. From experience though, they tend to be over spec anyway so you may find they just need to be of equal length if the truss is taking the load. 

[Nickfromwales]

On 23/12/2016 at 11:19, MarkH said:

His drawings only mentioned the purlin size, not the location of any joints.

Strange that he didn't identify the issue and provide a mitigation strategy in his return . He'd have known all about how far that timber could traverse before needing a joint so maybe next time you get charged for eye contact, bring that up . 

 

[MarkH]

Lap joints currently in construction. The purlins are joined at the trusses, both are notched for longitudinal restraint.

 

24 lap joints... I'm six in and already cut myself twice and dropped a beam on my toe.