Table of Contents
How deep? What size?
A simple side or garden gate.
This tutorial is given in both Metric (mm) and Imperial (inches) measurements.
The metric measurements are given first followed by the standard measurements in brackets ( )
For example: 100mm x 50mm (2″ x 4″).
A side gate or garden gate is usually placed to protect certain areas and/or to keep kids or pets in, intruders or animals out, or even just for privacy. Generally, a side gate or garden gate is about 1800mm (6ft) high.
As with all outside lumber structures, gates have to be designed to withstand the elements. It is a relatively common experience to have difficulty trying to open (and shut) some lumber gates that are either jammed between the posts, or have sagged and are dragging on the ground. A bit of forethought can alleviate these problems.
1: Posts. How deep? What size?
Lumber used for posts should be suitable for in ground application. That is, they should either have a natural resistance to decay (rot) or be suitably treated.
Post size: As a rule of thumb for free-standing posts, use 100mm x 100mm (4″ x 4″) lumber for narrow gates up to 1200mm (4ft) high, use 125mm x 125mm (5″ x 5″) posts for narrow gates 1800mm (6ft) high, and use at least 150mm x 150mm (6″ x 6″) posts for wide gates. A smaller size post can be used if the post is supported in other ways, such as bolted to another structure, held rigid at the top with a cross-member, or forms part of a pergola, arbor or other type of walk-through structure.
Hole size: For most, a lumber post should be concreted into a hole 600mm (2ft) deep and 300mm (1ft) square. A wider heavier gate such as a driveway gate, could require a hole 900mm (3ft) deep. Running a bridge made out of concrete or timber from post to post just below ground level, is a way of keeping the posts at bay against the pulling forces of the gate. (See diagram.)
Post spacing: Space the gate posts wide enough apart i.e. about 900mm (3ft), to allow for common garden and yard implements such as wheelbarrows, to go through.
I am a single female homeowner and I needed a side gate for my house and looked into a re-furbished iron gate. When I got their quote for $750, I thought “I could make my own gate for less than half.” The only problem was… I had NEVER done something like that before! It seemed to be basic enough, but again I had no idea what to do. I Googled “How to build a gate” and found your web page. I read the instructions, printed them out, and went to work. Your step-by-step instructions definitely helped me dodge the “trial & error” bullet, and I had very few “do overs”.
The one fear I had was cutting the diagonal brace(s) accurately. I laid the rectangular frame over the diagonal 2×4, and traced the lines as you suggested. Wow, what a great idea! It saved me most of my anxiety. I was using a skill saw for and did end up having to borrow my neighbor’s chop saw (and my neighbor) to re-do those cuts for a better fit.
I also wanted to show you my proud photos!
Thanks to you for your help. You saved me over $500! Plus I DID IT!
Carolyn Bell
I have just decided to build a side gate for the first time in my life and decided to search the internet for instructions and advice.
This was the first web site that came up in the search engine and I was pleasantly surprised to find a short, easy to read and understand tutorial with brilliant pictures on how to do it. I am confident now about building it after reading such wonderful instructions! Thanks a million!
Doug Christchurch, New Zealand.
It would be prudent to leave a note of caution if one wants to use the concrete bridge design.
Frost heaving is always a problem but with the bridge design the frost can easily lift the bridge portion of the gate.
This can obviously be a disaster.
I don’t understand how the diagonal brace will fit? Will it no clash with the horizontal brace ?