How to build a deck connected to the house?

[Imran24]

Hello experts...needing some advice for this new project. Have a few questions and appreciate any help with this long post.

We are planning to build a deck using Ekodeck with following details:

- Length: 5.6M, Width: 5M (Around 2.5m width is concrete slab and the rest 2.5 will be built on Soil)

- Attached to the house, on slight slope along the house

- Image attached detailing Post and Bearer design, annotated with comments.

- Slope from right to left is almost 400mm. Ground clearance on right edge is almost 300mm and on the left is almost 700mm

Here are a few questions:

- Can first bearer be replaced with Ledger (140 x 40 H3) attached to the brick wall using M10x100 (or 8x100), 600mm apart AnkaScrew 10mm x 100mm. If yes, can a termite barrier be applied between ledger and Bricks (if required at all). Note: Ledger will sit below peepholes and the deck will remain under the roof. Thinking to use Joist Hangers to attach joists with this ledger. Any downside of using a ledger i.e. any impact on bricks load bearing or termite risk?

- Posts under first bearer (Marked # 01 in the image) will be dynabolted to concrete using Ramset Dynabolt Gal 12mm x 70mm . Is this correct or should go for 100mm? Posts to be 1400mm apart, along the bearer and almost 1600 mm between two seperate bearers.

- First and second bearers will be made of 90x45 H3 treated pine, 02 off nailed together (marked # 01 and 02 in image). Is it good enough? The reason for 90mm is that I have less clearance on right hand side of the deck.

- Bearer # 03 in the image will be made of 140 x 45 H3 Treated pine (01 off). is it strong enough?

- Thinking of using a combination of Tuff Blocks and "In Ground Posts" on soil section as shown in image. Is this good approach? 

- For Posts in the ground; I will dig 600mm deep hole, place a brick at the bottom, place the post on brick, fill the hole half way with concrete and rest of the hole with dirt? Is it correct process?

-  All Joist connections with Bearers will be secured with Tripple Grips (using 90x45 joists).

@MitchellMc @EricL 

[EricL]

Hello @Imran24 

Please allow me to try and answer some of your questions. Before you begin, I strongly suggest checking your local council's rules and regulations regarding low-level deck sizes. 

• Yes, a termite barrier is a must and can't be skipped. The advantage of having a ledger is that you save on posts, and you have a strong anchor point which is the brick wall. Because you are anchoring to the house, it's very likely that you'll need a permit for your deck. But with a detached free-standing deck there is no need for a termite barrier and your low-level deck will likely not require a permit.
   
• For extra security, I suggest going with the 100mm anchor.
   
• It's better to use a nut and bolt configuration rather than just nailing the 90x45 together. 
   
• In regards to 140x45's capacity in load bearing situations in relation to your decking plan, I suggest engaging the services of drafts person, they'll be able to answer this questions more accurately.
   
• Use of various footings in deck building is an acceptable practice. 

Your last two questions will require the services of a drafts person.

If you need further assistance, please let me know.

Eric

[Imran24]

Thanks Eric for helping with questions. 
what termite barrier should be used in this case? 
i was also thinking of using washers between the ledger & bricks while running the anchors, to allow a few millimeters gap. Is this normally done/recommended?

[JacobZ]

Hi @Imran24,

Unfortunately, termite barriers are something you'll need to speak with a pest control specialist about.

Washers can be used as spacers to allow a drainage gap. Alternatively, you can use packers which are made from high-compressive strength plastic, so there is no potential for corrosion over time.

As @EricL has mentioned, there's a good chance a deck of this size and complexity will need council approval. We can offer guidance on how best to tackle the project, but we can't tell you what you are required to do in terms of compliance with local building standards. I'd strongly suggest contacting your local council to see what your legal requirements are for a project of this nature before continuing the planning process.

Once you've spoken with your local council, please don't hesitate to reach out as we'll be happy to assist further. 

Let me know if you have any further questions.

Jacob