Tutorial | How to design a safe deck? (design kit included)

[Sirine]

I recently tried designing a safe deck myself and found it quite interesting. I did my design in ZWCAD, but the logic behind the design process should apply to all kinds of CAD software. If you're interested in designing one yourself, feel free to download the sample drawings here .

Okay, here's how to design a safe deck.

Step 1. Prepare a plan of your house and its surroundings. Then, decide where to locate the deck and the basic shape of it, based on the plan.

Step 2. Outline the shape of the safe deck, which will be the base of your design. At this stage, your top consideration should be practicality. For example, if the ground were noticeably uneven, consider designing a multi-level deck.

 

Step 3. Draw the dividing lines on the deck to represent the placement of the wood. And don't forget to add dimensions to your design. For those who also use ZWCAD, you can use the Super Hatch function to texturize the deck with realistic wood images, to make it easier to read.

 

Step 4. Create the layout of the supporting pillars. You should allow for the moving load on the deck, which means the distance between two pillars is usually about 3 to 4 meters. In ZWCAD, you can quickly place the pillars with the Array function - first, select the pillar as the basic object, then set the distances on the X and Y axes.

 

Step 5. Design the elevation, which is mainly to show the height differences of the deck and its railings. Note that the deck should be lower than the house floor to prevent water from flowing back into the house during rainy days. As for the railings, the height is suggested to be 1 meter.

 

Step 6. Insert your title block in the layout space to display the necessary information, such as materials and size. Then, decide the paper size for printing out the layout. In this case, I think A3 is just fine.

 

With the printed layout, now you can contact your local contractors and discuss it with them. That's the whole process of designing a safe deck!

Edited June 30, 2022 by Sirine

[ReMark]

Actually, it isn't.  For one thing you left out the attachment of the deck to the house via a ledger board.  Many a deck has failed (i.e. - collapsed) because this was ignored or under designed.  Pillars, sometimes referred to as posts, do not typically rest on the ground.  Depending on where you live your local building department may require they extend below grade or at the very least sit on concrete piers.  And balusters (i.e. - spindles) are typically spaced such that a child cannot squeeze between them (100 mm center-to-center).  There is more to designing a safe deck than some may realize.

 

I also notice that you have neglected to show any supporting beams and the joists, if that's what they are, appear to be undersized.

Edited July 1, 2022 by ReMark

[BIGAL]

The building regs may also determine the offset from boundary limits, the height at a boundary plus lots more. 

 

The canterlever and hung would be difficult to construct as shown in section.

[Sirine]

Hey guys, thank you for the instructions! This tutorial is actually for those who at the Schematic Design phase. And the printed layout will definitely need further specifications and modification in the Design Development phase.

[BIGAL]

I have done structural design and this sounds way to big "the distance between two pillars is usually about 3 to 4 meters"  a deck has like a 5kpa floor loading as its considered a crowded area this is much more than interior house floor loading, 

 

If your going to do tutorials then they need to reflect building code examples. Where I am would do stumps at say 1500mm spacing max or would need a structural beam design.