Deck Site Preparation and Marking

Deck preparation and marking

A major benefit of a Softwoods modular deck kit is that a lot of the measuring and marking has been done for you. Other tasks that would have previously been done during construction and with annoying calculations can now easily be done before you even start construction.

Prepare the site by clearing away objects and obstructions from the work area. You will need to have approximately 200mm clearance to your finished deck height to have enough room to comfortably work and fit the bearers and joists.

Dig out the area if you need to gain some clearance. Check for potential drainage problems and make sure existing underground utilities like drains and pipe work do not conflict with stump locations. In case they do, you can move stumps 150mm either way along the bearer run when the time comes to connect the stumps to the panels. Once the site is clear you can mark out the perimeter with a string line. This will help you keep the structure square throughout the build process. To check that it’s square you can measure from corner to corner diagonally and adjust until even. Or use the “3 4 5 rule” — also known as the Pythagorean Theorem: A2 + B2 = C2.

If you are placing your deck into a corner area of your house (against 2 or 3 walls) you will need to check that the house is square at this point also. If it is not, you will need to make allowances.

To meet the Building Code of Australia requirements, it is recommended to have a gap for termite inspection of 25mm between the deck structure and your house. The stringline can also be used to keep the height on course so get it to a level that will be the top of the joists and bearers. This will be your finished deck height minus the thickness of your decking boards. Use a spirit level to check if it is level through the build process.

Once you have cleared out the site and have clearly marked where you will build, it’s time for you to get started with constructing your deck. Learn how to assemble the deck substructure, or get step-by-step instructions on how to build a deck from scratch.

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Attached gable pergola with timber liningIronbark deck over sloping site with inbuilt stairs and stainless steel balustrade

Softwoods is a family owned South Australian company that has been trading for over 30 years.


We understand that making changes to your home is a major and important thing, and we take care to understand that every project that we handle should be done with as much care as we would expect is used in our own homes. Learn more about Softwoods.

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Croydon, SA

573 Port Road
West Croydon SA 5008
Corner Rosetta Street

(08) 8346 1499

Modbury, SA

493 Wright Rd
Modbury SA 5092
Corner Wright & McIntyre Roads

(08) 8396 4044

Lonsdale, SA

28 O'Sullivan Beach Road
Lonsdale SA 5160
Corner Dyson Road

(08) 8384 5133

Perth, WA

Suite 15 Plaistowe Mews
102 Railway Street
West Perth WA 6005

1300 737 465