How to connect bearers to piies on low-profile deck?

[jamesmcrae]

Hi All , 

I have a question regarding piles to bearers . 
The deck is 10 m x 4 m  400 mm high ( ground to top of deck ) bearers will be flush with joists  , 40 piles @ 200mm deep . 
Which  way can  i connect the bearers to the piles ( see photos attached) 

Thanks for any advice. 
James 

 

 

[EricL]

Hello @jamesmcrae 

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about your low-profile deck.

The mounting options you've presented are both viable, the majority of the low-level decks I've seen often use (A). There is a third option and that is to do a rebate cut on the post and let the bearer sit in the cut. I've placed a sample image below. It is more work for you, but you get the advantage of both A and B mounting styles. The weight of the bearer is carried by the post and not the galvanized bolts. The galvanized bolts job now is to hold the bearer against the post without the bolts being stressed by the weight of the bearer.  

Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.

Please don't forget to post an update once your decking frame is assembled, I'm sure our members would be keen to see the progress you're making.

If you have any other questions we can help with, please let us know.

Eric

[Dave-1]

Evening @jamesmcrae 

I was going to go for an option C and @EricL beat me to it. Thats how I did my deck and I found it felt more solid? Its the only way to describe it. I prefer that the weight sits on the post iteself then being held up by the bolts. The Rule I know is no more then a third of width of the post (Tho looking back at my deck I have gone 50% on the 100mm posts mmmm ) should be notched which is also what EricL has drawn. 

Dave

[Nailbag]

Hi @jamesmcrae 

Either (B) (click link for video) or @EricL rebated version of (A) would be the structurally correct options.

Nailbag

[jamesmcrae]

Hi Eric , thanks for that , this would be more work , but  a lot more solid  , if I was to use this method would I  galv bolt or just screw to bearers to piles ? Cheers 

[Dave-1]

Morning @jamesmcrae 

I like the gal bolts, mainly because they dont chance splitting timber and the ease of install. Screws may loosen over time but really person preferance comes to mind. You can purchase boxes of the bolts that work out way cheaper then indervidually.

And yeah more work but in several years time when you see someone else doing "maitenance" on there deck and you can walk out on yours with a coffee in hand... Solid as a rock... You will be smiling

Dave

[JacobZ]

Hi @jamesmcrae,

As @Dave-1 has said, either option will work, but I am more inclined to use ZENITH M12 x 150mm Hot Dip Galvanised Cup Head Bolts And Nuts with a Macsim 50 x 50 x 3mm M12 Galvanised Square Washer on the back.

A nut and bolt will create a far stronger connection that is better at handling the shear forces that are often applied to bearers. The square washer will also help to distribute the load applied by the nut across a wider area.

It is also far easier to retighten a nut than it is to replace a screw that has loosened over time.
 

Let me know what you think and if you have any further questions, don't hesitate to ask.

Jacob