Three-tier deck and pergola

[Itai]

Hey all,

I'm busy planning my deck and pergola. This is what I'm thinking at the moment.

I thought the 3 layer deck would be nice (total deck length is 9m, pergola length is 6m, highest deck is 35cm above ground). 

I was thinking of using the lowest deck to put a lounger couch on, but not sure it takes up too much space. Also, not sure the planter box along that deck makes sense either? It's around 45-50cm wide.

In the designs, I've staggered down the planter boxes. The deck is 3m wide at the top, and 3.15m wide in the lower part (from house brick to planters).

The part without deck goes off into our garden.

Fence is colourbond 2m above ground (so 1.7m above the higher deck).

I also have no idea where to put the BBQ or if I should build in a BBQ area, or simply use a portable to make the space bigger.

(I can add some screens without plants if that helps).

Here's some designs

Would love your thoughts.

Regards

Itai

[Itai]

Hey @MitchellMc 

1 More question. How would you recommend attaching the rafters to the beams? I'm not sure what the right product is.

[MitchellMc]

Hi @Itai,

The Merbau laminated posts would be perfect and provide adequate support. I believe most of our H3 outdoor timber will have those milled lines on the surface. I'll investigate what other options there might be.

How are you constructing the deck? Are you laying joists down which the brackets will attach to, and can you let me know which bracket you are referencing?

Notching the rafters so they slot over the beam and lock into place would be a suitable method. I'll include an image below to illustrate.

Mitchell

[Itai]

Hey @MitchellMc 

Here is the designs I'm imagining:

The top of the brick by the door is roughly 32-35cm above ground. So was thinking a 240mm bearer + a 90mm joist on top + 10mm off the ground. 

I was imagining something like this bolted with 2 x M10 ever half meter or so: https://www.bunnings.com.au/carinya-heavy-duty-75-x-75-x-40-x-3-5mm-zinc-plated-angle-bracket_p00469...  or this https://www.bunnings.com.au/carinya-100-x-100-x-50-x-4-5mm-zinc-plated-angle-bracket_p0046899

(Side question, on the latter one, if I drill additional hole in the centre, would that significantly effect the structural integrity?)

My only concern with this method is levelling, I only have like 1-2cm to play with if I'm lucky with this method and my concrete slab is sloped towards the house slightly. Also, I'm unsure what the level is parallel to the house over 6m (haven't really had anything long enough to measure)

I'd be happy also with using some sort of a bearer support and a smaller bearer, but ability to adjust is key.

Further down, the deck steps down, and looks something like this:

On that pergola join, is there any bolting / nailing somewhere? I assume it's not just notched and sitting there and that's it?

Thanks

Itai

[MitchellMc]

Those brackets look like they would work @Itai. You might like to switch to adjustable pedestal feet in the areas where you need further adjustment. I can't see why drilling another hole in the middle of the bracket would be an issue. 

For the pergola join, you would nail diagonally through it, fixing the timber in place.

Mitchell

[MitchellMc]

Hi @Itai,

One of our timber suppliers TasmanKB does Dressed All Round H3 Pine which doesn't have those micro-lines. It's available through our Special Order desk at your local store. 

Please let me know if you need any assistance in ordering this product.

Mitchell

[Itai]

Hey all. Pergola roof structure is almost complete

I'm now looking to move onto the deck.

I'm going to be attaching the deck to the concrete, and was just seeking some advice.

I was planning on running 4 x 6m bearers to cover a deck width of 3.1m, at approx 800mm-900mm spacing between each bearer + another 700mm between the deck and the house which I will attach a 90x45 ledger to the house.

I initially calculated using bearers of 140x45 as I'll be attaching to the concrete every 1m, so they're not spanning very long. But some deck span tables show 2 laminated boards rather than a single, i.e. 2/140x45.  (I'm using external framing timber MGP10)

For example: 

 

Can I use just a single 140x45, or do I need to double them?

I'm attaching to the concrete with 130x130x5mm angle brackets with M12 bolts and M12 ankor screws, super solid!

For reference, the joists will be 70x45 as 90x45 will be too high for the deck height (140mm + 70mm works out well for me). And I will space them at 600mm (as the span will be continious span less than 1m between bearers)

Thanks

Itai

[StevieB]

Thanks so much for sharing an update @Itai. It's great to follow along with your project.

@MitchellMc will be happy to help when he's back on the site on Friday. Thanks for your patience in the meantime. Let me also tag @Adam_W to see if he has any thoughts to share.

Stevie

[Itai]

I've decided to stick to the 45mm and not laminate the two together. My neighbour is a builder and said with my installation technique, it's actually all over engineered and I won't have any issues. Especially with supports every meter on the bearer and a Floor Load Width of 800-1000 max because I have so many bearers. I do believe in over-strengthening rather than under!

However, my work came to a halt for the weekend. I was installing the ledger which was going to be used as my reference point for all the other bearers. I was using some 250mm landscaping screws to attach the ledger directly to the bearers under the house (brick veneers house on stumps) and somehow I managed to find the exact centre of a copper water pipe which I screwed straight through! (Those are some tough screws!)

I ended up having to remove some bricks and clamp the hole shut with this product: https://www.bunnings.com.au/plumbing-clamps-scl_p4920569 ... it worked a treat and I was able to continue using my water until the plumber came out today. This $25 saved me the additional call out fee for an emergency plumber on the weekend! 

Plumbers repair

Bricks all patched up again

Will have to change my approach with the ledger now though. I'll still put a few landscaping screws, just will be cautious about where I drill. And the rest I will do with 12mm Ankor bolts into the mortar joins cutting into the brick. The advantage is this doesn't have to be the strongest hold, because I've got another bearer at 450mm away which will be dealing with the brunt of the load, and none of the load from the main deck area will hit the ledger. It's really only there to stop flex when you step onto and off the deck.

These are the screws I used which drilled straight through the copper (The screw itself is what drilled through using a driver)... I'm super impressed! https://www.bunnings.com.au/buildex-18-7-x-250mm-landscaping-construction-screw_p2410358

[MitchellMc]

Hi @Itai,

I apologise, as I must have missed your question. You don't need to laminate two boards together. You just need to make sure the supports for the single length match the span table requirements.

I'm sorry to hear of your mishap. It looks like you are still making great progress, though! As you've mentioned, I'd recommend putting in a few more Dynabolts of Ankascrews into the brickwork to compensate.

I look forward to your next update instalment. Please let us know if you need any assistance.

Mitchell

[Itai]

Hey @MitchellMc 

Thanks for the response. Haven't done anything since with the crazy Melbourne weather!

Just a few questions (and I read some stuff you wrote on a low level deck thread). Should I be putting protectadeck between the brick and the timber for the ledger I'm attaching? It's 140mm timber, which would need two rows of protectadeck. Or should I use another type of flashing, or it's just not needed for the ledger because brick "breaths"?

I'm attaching the bearers to the concrete slab, and am running joists over the top of the bearers. I was planning on using these brackets to attach:
https://www.bunnings.com.au/dunnings-130-x-130-x-65-x-5mm-m12-galvanised-angle-bracket_p1070080 (Where the bearer runs within 20mm of the ground)

https://www.bunnings.com.au/dunnings-150-x-150-x-75-x-6mm-m12-galvanised-angle-bracket_p1070081 (Where the bearer has to run higher off the ground to maintain the deck height along a slight slope, say 30-50mm).

My question is, would I encounter any issues if I drilled a 3rd hole in the centre of the brackets as sometimes the bottom hole is too close to the edge of the wood (sometimes not even contacting the wood). From what I've been told, with this type of steel, and the force being down, I shouldn't see any issues.

Would a spacing of approx 1m be ok with these brackets (they are holding up the bearers, not just the joists). My guess is with the strength of these things, 1m spacing would be ok. My minimum bearer is 140mm so I'm not worried about span lengths. This is along a 6m bearer (so 7 brackets each, alternating sides).

I did have my neighbour take a look, who is an old school retired builder, and he seemed to think I've gone and overengineered so should be ok. But wanted to get your opinion.

Thanks

Itai