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How to attach joists to end rims for deck extension?

tejmankar
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How to attach joists to end rims for deck extension?

Hi,

I am extending my deck and planning to build a long bench on top of it. The bench will weigh roughly 500kg by the time I build the frame using 90 x 45 h3 and then completing it using composite decking boards on the face. The bench will be 4.4m long. I would appreciate some guidance on the flooring frame please. The frame is roughly 6.4m x 1.2. I have supported the rims using stirrups every 1.2m. I have joined the joists to the rim by using two bugle screws (100mm) on each end. The joists are roughly 450mm apart. Is it sufficient to have joists joined using the bugle or is it better to also add joists hangers please to give the structure the strength to support 500+ kgs. The boards on the frame are temporary to walk easily. Many thanks

 

 

 

.20211223_092428.jpgExisting deck extensionExisting deck extension

Re: How to attach joists to end rims for deck extension?

I'm building a small deck myself at the moment and have also been held up by timber supply issues @tejmankar. I finally managed to source some joists the other day.

 

I can't wait to see your project finished. Keep us updated.

 

Mitchell

 

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tejmankar
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Re: How to attach joists to end rims for deck extension?

Hi @MitchellMc 

 

When I started digging to add the two additional posts, I found an ag line roughly 400mm from the surface where the first post should be located? What are my options here please? Will I need to reroute the agline or can I pour concrete over it ? Haven't dealt with aglines before :smile:

 

Also, where I dug for the second post I found that the storm water drain pipe is cracked. Is there a way to repair it please? Thanks.

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Thanks,
Tej

Re: How to attach joists to end rims for deck extension?

You're very close to that stormwater pit as well @tejmankar. Probably not the best idea to place a footer directly above and agline. 

 

I'm not sure why I didn't notice this earlier but is that bearer doubled up? What's the thickness? I presumed it was a single 45mm thick bearer spanning (approx) 1.8m(?) to the post, and that's why I advised additional posts in-between. If that bearer is two laminated timbers at 90mm thick, it's should be fine as is and the deck appears to be already over-engineered. I now don't feel a post is necessary where the drain is.

 

Mitchell

 

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tejmankar
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Re: How to attach joists to end rims for deck extension?

Hi @MitchellMc 

 

The bearer is doubled up 190 x 45 x 2.  Please find photos attached with distances. I managed to dig out the ag line if a post is required and I have also dug up to repair the cracked pipe. You reckon the additional posts are not required please? Can I add the additional joists without the additional posts? Look forward to your thoughts? thanks.

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Re: How to attach joists to end rims for deck extension?

Even a single 190 x 45mm would be adequate to span those distances @tejmankar. The two are more than capable. I don't believe other posts are necessary, even with the additional joists.

 

Mitchell

 

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tejmankar
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Re: How to attach joists to end rims for deck extension?

Hi again @MitchellMc ,

 

One more question. Since I have got all the material now and dug up everything, if I am wondering if I should just install them. I can move the ag line easily now. How far do I have to be from the storm water pit to install the post please?

 

Other option is to return everything back :smile:

 

Thanks,
Tej

Re: How to attach joists to end rims for deck extension?

Might as well install them now @tejmankar. If you can set the footer back 10cm from the pit that should be plenty.

 

Mitchell

 

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tejmankar
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Re: How to attach joists to end rims for deck extension?

Thanks @MitchellMc  and in terms of distance from the storm water pipe, would that be 10cm as well please?

 

Regards,
Tej

Re: How to attach joists to end rims for deck extension?

Yes, @tejmankar. Just enough gap that they wouldn't touch each other with any movement. You could likely bring the pipe right next to the foundation; I just don't want it to settle and crush the pipe on you.

 

Mitchell

 

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tejmankar
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Re: How to attach joists to end rims for deck extension?

Hi @MitchellMc 

 

The posts are in. Please find some photos attached.

 

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Post copy.jpg

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