What's the best way to hang weight from angled surface?

[Phenotype]

Hi all, I'm not experienced with DIY but I'm hoping I can avoid screwing this job up with a bit of advice.

I would like to hang a pulley system from my carport roof so that I can store my roof box in the roof space.

The problem is the rafters are at a 45 degree angle, which would greatly reduce the strength of an eye bolt.

I've attached an image showing the two rafters I would need to hang the pulleys from. The total weight would be about 25kg spread between the two rafters.

Do you think the rafters can handle the weight and what would be the best attachment to connect the pulleys with the rafters?

Any advice greatly appreciated!

 

[23vc]

Do you think the rafters can handle the weight and what would be the best attachment to connect the pulleys with the rafters?

1. Yes
2. Bolts/big screws

 

[^woody^]

Just screw the eye bolt in. Vertically or horizontally as you like.

 

[Phenotype]

Do you think a couple of these would hold the weight? From what I've read these sorts of bolts lose a lot of their strength when being pulled at an angle https://www.amazon.co.uk/Dutyhook-8X80-Thread-Stainless-Steel/dp/B001MSCEE4/

 

[JohnD]

That's a screw eye.

An eyebolt does not rely on the thread so I would prefer it. You can get them with a flanged head or "collar" to help hold them straight. Long-shank. And a nut and washer on the other end.

If you fix it vertically there is no twisting force, but you will want a plate or large washer under the nut.

Or you could use a shackle.

 

[Ian H]

Or you could use a shackle.

A big one of these:

https://www.screwfix.com/p/hardware...KmnpZLSq87LtcQYiECsUweR8hpSobp-hoC5OIQAvD_BwE

 

[Harry Bloomfield]

Better /stronger would be a pair of made for the job steel U shaped hangers, with a long bolt horizontally through the side of the U, the wood and the far side of the U.

 

[bernardgreen]

Remember that if the lifting ropes go horizontally from the fixing at the rafter then there will be a horizontal force on the fixing as well as the vertical force.

 

[Notch7]

Oh dear, very risky.

I would contact a structural engineer straight away.

Maybe it falls under building regs, Id say go for full plans submission, better safe than sorry.

Oh and Im sure it falls under working at height regulations, you might be best fitting a guard rail.

 

[cdbe]

These things are a complete pain in the arse! Just to take your kitchen sink on a 2 week camping holiday. Mine is sitting on 2 shelf brackets strapped to the wall as I have no roof space to store it in.

In your case I would just run a couple of horizontal 3x2's across from the rafters to that beam on the right, spaced a bit narrower than the length of the box and just sit it on top.

 

[23vc]

I’ve tried to do some proper calcs for this, but can only find loading data for masonary, timber floors etc, can’t see roofboxes on there.

 

[motorbiking]

If you plate the rafters with some ply and ensure the mounts go through both then you spread the load from one rafter each to say 4. This significantly improves the attachment.

 

[charliegolf]

It's 25 kilos. Blu tack won't quite do it, but most other decent fixings will. This is being over-thunk!

 

[Harry Bloomfield]

It's 25 kilos. Blu tack won't quite do it, but most other decent fixings will. This is being over-thunk!

Almost inevitably, more weight will be added than the OP expects, so worth making it robust.