Stirrups

[Chumley]

G'day all,

It never ceases to amaze me how you can get stuck on some minor detail -- minor to those who know how, but a major re-invention of the wheel for those who've never faced that particular thing. I'm in the process of planning a hexagonal gazebo with a timber floor. Got some advice on a different thread about how to lay out the bearers and joists - will have a series of bearers in a hex shape (prob 6x3 treated pine sleepers), with one bearer going diagonally through the centre from opposite joins (see pic 1 and or 2 below - wasn't sure if a sketch-it picture would be readable, so I jpg'd it as well).

So, 4 of the corners will be a meeting of 2 bearers - with a 120º join - if I want to hold this corner up with a stirrup in concrete, do I need 2 stirrups or is there some way to do this with a single stirrup? Same problem with the other 2 corners which have 3 bearers meeting, the 2 outside ones and the centre diagonal - I guess I can use 3 stirrups (see pic 3) - but is there some way to do this with one?

Cheers,
Chumley

[Wood Butcher]

You could make custom stirrups that support all three bearers. If you don't have access to a welder it could be expensive to have them made though.

[pawnhead]

You could use T blade stirrups (http://www.biggee.com.au/POST-SUPPORTS_files/image016.jpg) between the external bearers. Get them from Big Gee (http://www.biggee.com.au/PostSupport.html) if they don't stock them at your hardware. The flange is probably longer than 100mm, so you'd have to cut it down and just use a single bolt. Just use universal framing anchors (http://images.orgill.com/200x200/8876906.jpg) (sometimes called 'multigrips') to fix the internal bearer.

http://i7.photobucket.com/albums/y266/holgerdanske/th_Untitled-Captured-01-8.jpg (http://i7.photobucket.com/albums/y266/holgerdanske/Untitled-Captured-01-8.jpg)

[pawnhead]

Alternately, just use a single sided bracket like so:

http://i7.photobucket.com/albums/y266/holgerdanske/th_Untitled-Captured-01-9.jpg (http://i7.photobucket.com/albums/y266/holgerdanske/Untitled-Captured-01-9.jpg)

edit: But aren't you having posts and a roof or a handrail of some sort? If so, then your posts should be in brackets, and they should be supporting your bearers.
You know you're supposed to have 300mm ground clearance to your bearers.

[Chumley]

Hi John,

Thanks for chipping in again (no pun intended). I think I'll go with the first option and use the t-blade - the central bearer will have a stirrup of its own in the centre of the gazebo, so the sides will be fine with a couple of multigrips.

I will have wall panels and handrails, but will make them as 6 separate panels using 3x2 treated pine (one with doorway) kind of like the internal framing of a house, so no posts as such. Roof will sit up on the panels. There is one of the same design at work made by our resident carpenter - but his was set in concrete, so the base is different.

Had no idea about 300 clearance to the bearers - seems excessive since I sometimes see treated pine in the ground! Hmm, maybe I should do some more research on building specs.

Thanks again for the advice - 'tis invaluable.

Woodbutcher, I don't have a welder and as you say would probably be expensive getting some made up.

Cheers
Adam

[pawnhead]

Had no idea about 300 clearance to the bearers - seems excessive since I sometimes see treated pine in the ground! Hmm, maybe I should do some more research on building specs.Yeh, you're right there. There's different grades of treatment though. With H3 treated pine (such as sleepers) you can just sit them in ground. :2tsup:

[Chumley]

Just noticed that stirrups normally come with 2 bolt holes for the post/bearer - if you look at the face of the stirrup there is one top-right and one bottom-left. This seems ok if the post sits on the stirrup or if it's the middle of the bearer sitting on the stirrup, but when the stirrup is the meeting place for 2 bearers, wouldn't you want to have 4 holes? And if the answer is yes, and you drill another couple of holes, does that negate the 'hot-dip-galvanized' nature of the stirrup, making it a potential rust issue?

As always, any advice appreciated.
Cheers,
Adam

[pharmaboy2]

wouldnt you simply house out both bearers 50% and bolt through both bearers with the same 2 bolts? seems easier than drilling a 10mm hole through a stirrup?

[Chumley]

wouldnt you simply house out both bearers 50% and bolt through both bearers with the same 2 bolts? seems easier than drilling a 10mm hole through a stirrup?

Normally yes, but in my particular instance the bearers are meeting at 120 degrees rather than 180 ('tis a hexagonal gazebo in the making) and the angle makes a lap joint impractical so I plan on using mitres but need something to pull the mitres together, hence the four bolts. I guess I could use just 2 and use some treated pine wood screws but I'm not sure they will last.

Cheers,
Adam

[WA_decker]

Hi there,

Thanks for the info in this post. I have the same type of question as this but will have more than three bearers meeting together. What I would like to know is what to use for 5 bearers joining up using 5 stirrups. I am at around 40 stirrups for this deck and I basically don't want to dig that many holes. Any tips would be good. One concern is a 200kg table made out of a nice 5cm jarrah slab which I was thinking may need its own bearer and stirrup supports under where the legs are going.

See attached pics. The second one is from further up this post. Wasn't sure if this could also be appied to a five bearer intersection. All the others are from my plan.

Any advice well appreciated...:2tsup:

WA_Decker.

[pawnhead]

Chumley's deck would have all the boards running in the same direction. With your design have you considered the look of the decking converging to a point at the middle of the hexagon, and is that what you want to achieve? Certainly more hassle to lay the decking that way, having all the ends meeting up (without creeping out of line) and getting shorter and shorter as they converge on the centre. You'd also have to be careful to start your first board (or your first gap) at the converging point, otherwise you'll end up having to rip down the centre board (right along the main deck) which would look a bit dodgy.

Personally, I'd just run them all the same way. I think it would look a bit weird otherwise.

edit: If you did want to do it as drawn, then I'd set the converging bearers at the same height as the joists (to support the decking), and the North/South? bearer beneath them. Then you'd just need one bracket on the lower bearer, with the other four just sitting on top of it, all just nailed together, with a framing anchor just on each of the outer two. :2tsup:

[silentC]

Aren't you going to need to double up on those hips? If I was building that, I'd want enough joist to nail in a 50mm board to butt all the mitres up to on either side, much easier and neater than trying to get them to all line up. Same way that you handle a 90 degree turn in a verandah. That would probably mean running two hip bearers side by side with a gap in the middle.

[WA_decker]

Aren't you going to need to double up on those hips?

yes I was planning on doubling the hips and hanging the joists between. Now you have got me thinking about what finish would be best on the laying of my deck. I might start a new thread with some suggestions of possible looks and go from there...hopefully this won't mean starting from scratch again...but hey its good to get ideas. Thanks guys. I will post around 6 designs. I would appreciate your feedback as to which ones you prefer....