Supporting loft purlins with struts...angle issues

[Leofric]

Assuming you accept the strut at an angle is acceptable , if gravity is acting downwards wouldn't that strut need to be the other way round , that is with the notch out of the wood at the top so the purlin bears on to the ' meat ' of the wood

 

[tony1851]

Assuming you accept the strut at an angle is acceptable , if gravity is acting downwards wouldn't that strut need to be the other way round , that is with the notch out of the wood at the top so the purlin bears on to the ' meat ' of the wood

Ideally, yes, but then I should really be living in the Bahamas and not Manchester.

 

[John D v2.0]

if gravity is acting downwards wouldn't that strut need to be

That's interesting, I'd always assumed in a triangulated roof, the purlins and struts were to prevent the rafters deflecting rather than support them against gravity. The ceiling ties wouldn't really stretch so the point supported by the purlin would not go straight down but keep the same distance from the rafter feet. Hence the force would act perpendicular to the rafters rather than downwards.
In a roof with a ridge beam or similar i understand that all the forces would be vertical, and i don't think it's clear what kind of roof this is (as a diyer!)

Any thought I'd be interested in whether that makes sense?

 

[Leofric]

Ideally, yes

Good , so you agree ,can you tell John D

 

[John D v2.0]

Good , so you agree ,can you tell John D

I'm not sure if you're mixing me up with another more popular member, but feel free to explain it yourself as I'm interested in learning from others

 

[^woody^]

another more unpopular member

Sorted