Building a Timber Deck

Choose desired location for new timber deck.
In this case concrete footings where poured to support the deck.

Work out where the finished height of the deck is.
In this case the decking is going to finish underneath the sliding door.

Subtract the thickness of the decking (20mm) then the height of the joist (140mm) and that is the height of the plate (whalan plate)

Fasten the plate (whalan plate) to the brick work.

If the bricks that you are fastening to are hollow then use nylon plugs (make sure there is a minimum of 70mm fastening into the brick work.)
make sure you drill the hole in the centre of a brick.

Secure and drill holes every 450-600mm apart making sure to alternate the holes at the top and bottom of the plate.

Set up the end joist, by nailing or screwing it to the plate.

Using a level make sure you level the joist and use an offcut of timber to support the other end, remember that the support on the end is only temporary.
now make sure that your joist is perpendicular to the plate so there are two methods you can use.

First method is to use a builders square. hold it on the internal corner of the plate and joist. Using a piece of timber nail one side to the plate and the other to the bottom of the joist.

Second method to use is what we call 3,4,5 method eg. measuring from the internal corner where the joist meets the plate. Measure 3m across the plate and put a mark.
Then from the same internal corner this time measure 4m along the joist and put a mark.

Now you need to hold the tape measure on the 3m mark. Measure diagonally to the 4m mark when your tape measure reads 5m exactly, then that will give you a 90 degree right angle.

Repeat step 3 on the opposite side of the deck.
Using a string line run it along the top of the joist from one end to another and set up a few more joist in the middle, this will help you set up for your bearers.

Depending on the size of your deck and the size of your timbers this will determine the distance between your bearers.

In this case I am using 140x45 Treated Pine (TP) joist and 190x45 TP bearers. the deck is 3.6 wide fro the house so I will need 2 rows of bearers at 1.2m apart.

Nail or screw the bearers to the underside of the joist. If you are finding it hard to hold the bearer up you could nail a block to the side of the joist and the side of the bearer to help, remember that its only temporary.

Remember do not place your temporary props too close to where your posts are going to go.

By this stage you should have all your bearers in and ready for your posts.

half notch the posts so that it will support the full thickness of your bearer.
In my case my bearers are 45mm thick and my post is 90mm thick so I will notch half.

If your posts are sitting in the ground then dig a hole approx 300mm x 300mm x 300-400 deep. make sure you use timber tgat is suitable to go into thr ground eg H4 treated pine.


If you're post are sitting on concrete or concrete piers then a shoe will be necessary to secure and support the bottom.

To get the exact height of the posts place the shoe in its location and measure from the top of the shoe to the bottom of the bearer ( that will be the measurement to the notch then add the depth of the bearer.

dyna bolt shoe to concrete and screw the post to the bearer.

Put all your joist in at the required spacing which in most cases the required spacing is 450mm apart.

When you are putting the joist in keep the bow if the timber ( if it has one) facing upwards so that with the weight it will straighten.

Start your first decking boards againts the house and work your way to the outside.

Use a string line or a chalk line to make sure that the first board is straight.

lay your decking boards down and make about 10 rows making sure that you alternate where each joint is and always make sure that each end is supported at least a minimum of half the thickness of your joist.

Timber decking needs to have a 3-4mm gap to allow it the expand

I use nails as my spacer but you can use something else.

Setting up the 10th boards is the same
same as step 8 except put your packers in between each board
before screwing or nailing anthying down.

Repeat this same step untill you reach the end of you deck.

Your deck is now complete.

Anything hanging past leave to the end to cut off.

Be careful when using power tools and if you need anymore advice or if your are uncertain please do not hesitate to contact me.

I hope my step by step guide will help you in achieving your goal. Finally, enjoy your new deck!