Ballustrade on internal skywalk

[Pat r]

Hello.. I might not have my terminology correct here.. I am looking to put a ballustrade on a 5m long skywalk. I want to make sure the newel posts are secure and able to resist outward forces. The skywalk is in the middle of building so will need a ballustrade on both sides.. I have attached a pic of an idea I have to attach the posts and am wondering if it's up to scratch. The newel posts are 90mm x 90mm. I have not drawn any spindles. These will most like be fixed into the side of the oak cover board through to the beam ( much like the newel but without the half lap and a smaller single fixing) the 2 end posts will be fixed into the block wall on one end and timber stud wall on the other.. i hope this is clear and thank you.

h

 

[Richard Berry]

I have 2 concerns. The first is that there is too little material left at the bottom of the countersunk bolt hole to be secure. If the post is 90mm which you're halving for the lap joint, then halving again, that doesn't leave much meat.

Secondly, the lap joint effectively creates a lever with the fulcrum at floor level (I'm assuming that the floor will be supported on top of the 8x4 structural beam). That creates a lot of force if someone were to lean against the top of the post there is a distinct possibility that it could split the post since the entire outward force is now supported by only 45mm of material.

This is really something you should refer to a structural engineer.

 

[TheTiddles]

I’d move the post fully to the outside and sit the cladding boards between the posts instead of under them, reducing the visual impact of that move. That should make your calculations easier for strength of the post (which I’d guess will be fine unless it’s used for a James Bond fight scene) and for the bolt strength too

Aidan

 

[Darrenp]

If this is being built in a public/work area there will definitely be standards/codes that will have to be adhered to !