How To Construct Your Own Decking Framework

Although building timber decking for your garden is a fairly straightforward job,  it truly adds a whole lot of value to your outdoor space.

A deck gives your garden real character and provides a more enjoyable spot to relax/ dine/ hang out. Decking provides the perfect platform to chill with a good book in the warm summertime, but it can also be the perfect stargazing spot on a frosty winter night. It’s versatile like few other garden elements.

Constructing it yourself is pretty straightforward and it will feel like a great achievement.

It can be difficult knowing where to start, how to plan, and how to construct a decking framework, so we’ve made this guide to help you out.

Let’s get started on building your new garden deck:


Planning Permission

Before you can begin any construction work, you must check that you have planning permission to build your decking framework.

For basic decking projects in most gardens, you’re most likely okay to go ahead but we’d recommend you always check with your Local Planning Authority before getting too far — just to be sure that you are OK to start building.

You can read more about the specifics of planning permission here.

It’s always nice to check in with your neighbours too if you’ve got a particularly ambitious project in mind!


You’ve got to envision the end product if you want the construction process to run smoothly, so get your thinking cap on!

Think about some basic questions.

Where will it be located? What will you use it for? Will it need stairs? Are you going to build it all yourself? What material do you want to use? What is the foundation like?

Once you’ve got the answers to these questions, you should have a firmer idea of what you equipment and materials you’ll need to buy, what work is required, and what kind of long-term maintenance will be involved.

Answering these questions will also help raise any red flags in advance, preventing waste of materials and your time before you start hacking off bits of wood!

At Stewart Timber, we have a handy decking calculator so you can work out the estimate cost of a project and how much material you’ll need. Using this will keep you on the right track!

At this stage, you may also decide to invest in one of Stewart Timber’s decking kits which will ultimately save you a lot of time and effort, still resulting in a gorgeous decking framework built by you.


You’re going to be working with sharp saws, drills, and various chemicals when constructing your decking framework so you need to make sure you’re keeping safe.

Safety goggles, protective gloves, and sturdy shoes are crucial.

When using equipment and chemicals, always follow the manufacturer’s instructions for proper use to avoid any nasty accidents.

Prep The Area

You’ll need a good foundation to support your strong decking framework.

Firstly, clear away any plants, weeds, stones, and any other things in the area you want to build the decking so nothing will get trapped in the framework, causing it to rot or go lopsided.

Then, cover the area with weed control fabric to stop those pesky weeds you’ve just plucked from making a comeback. Weigh down the fabric with gravel or peg it in place.

Your decking framework should be level so make sure the ground is even before going any further.

It’s a good idea to lay concrete slabs in the corners and centre of the area to keep your framework off the ground, helping to keep it level and dry.

Preparing The Boards

Now it’s onto the real manual labour!

If you’ve already got one of our decking kits, great. You won’t need to worry about sawing and measuring the decking boards.

If you’re starting from scratch, measure your boards and mark them in pencil at the desired length. Measure twice to make sure it’s right. Use a combination square to draw an even line across it. Once you’re sure it’s the correct length, saw it to size.

Once your boards are the right size, apply protective treatment to the cut ends. Now it’s time to assemble your sub-frame.



Constructing The Sub-Frame

It’s a good idea to do a ‘dry run’ of the decking before you start putting screws in place so you can get a rough visual of what it’ll look like at the end.

You should assemble the components in this dry run so they have a ~5-8mm expansion gap along the length of the boards and 3mm gap along the ends of the deck boards.

Once you’re happy with how it will look, it’s time to assemble it for real. Mark with your pencil where the two outer joists meet the inner joists on the pieces of wood you’re using for the frame. This will give you a guideline for where to insert the coach screws. In total, you should have eight marks.

Drill recesses into these marks, ensuring that the screw heads will be flush with the joint. Fit the coach screws in place and make sure everything is secure. This should be your outer frame completed.

Secure the inner joists by driving coach screws through them from the outer frame so it all fits snugly.



How To Lay Decking

Again, do a trial run before rushing into securing the decking boards in place.

Lay the decking boards across and in the opposite direction to the inner joists, ensuring everything is flush.

Remember your expansion gaps lengthways and breadthways when cutting the boards.

Once you’re happy with the look of it, screw the boards into every joist, covering the full frame. Start by screwing the ends of the board in place, then the joists in between.


Although all of Stewart Timber’s wood is pressure treated, you should keep your decking in tip top condition by cleaning it with decking cleaner and then sealing it.

You can use a specialised sealer, stain or paint to do so, and you should recoat it every couple of years to prolong its life.

Make sure that all the saw cuts and drill holes have preservative added to them too.

Check out this post for more information about how to maintain your deck.

Now your decking is done and dusted, look after it by keeping it clean and clear regularly.

Ready To Get To Work?

By investing in decking material from Stewart Timber, you’ll be investing in premium pressure treated timber that will protect your decking wood from insects, dampness, and decay.

We have a selection of full decking kits and individual decking components for you to choose from

So, if you have a decking project in mind, check out our decking calculator or contact us directly. Our team of decking experts will be glad to assist you!

Related blog posts

Reinvent Your Deck

It’s easy to install your deck then leave it as is. Not that that’s a bad thing. If you got your deck from us, it’s a fine deck, after all. Some might say it’s a mighty fine deck! But if you leave even the best deck unchanged for years, it can get stale and boring. Every […]

Deck Maintenance For Dummies (And Regular Folk)

Is your garden deck looking rather grey and boring? Unfortunately, ‘tis the season for gloomy grimey garden decks. Fortunately for you, we’ve done some digging and asked around in the timberyard for tips on how to best maintain a garden deck. We know it’s only January, but the sun will be out before your know […]