How many fence panels do I need?

If you want to calculate how many fence panels you need for your garden fence installation, we’ve put together this handy guide.

For some gardens, your calculation will be simple, and you can quickly determine the number of panels by:

1. counting how many panels are already installed or

2. measuring the ​‘fence run’ i.e. the length that you want your fence to be and converting that into equivalent panel width.

The challenge is, garden plots are not designed to be perfectly uniform for fencing, meaning that the majority of fencing installations require additional measuring. Remember, in the UK, a standard fence panel is 6ft imperial (1.83m) wide but imported European panels are usually 1.8m wide, which, at 3cm less per panel can make a difference over a longer run. Most panels are available in various heights from 2ft up to 6ft as standard.

Step 1: Measure the space

If you are replacing an existing fence:
You can measure the length of the existing fence, including the posts, with a tape measure or measuring wheel. Measuring wheels can be easily hired if you don’t have one.

Top tip: make sure you keep the tape measure straight rather than accounting for variations in ground height. Your tape measure should be level across the fence, rather than following the top of the fence line which may vary.

If you are installing a brand-new fence or changing the fence position:
You will need to take an accurate measurement that accounts for variation in ground level.

If your ground is level:
Place a short stake at one end and a short stake at the other and then measure between the two points. A fencer’s line can also be a useful tool for marking this.

If your ground is sloping or variable:
The most accurate way to measure for fence panels on sloping ground is to insert a taller peg at the lower end of the run and a shorter peg at the higher end in order to get a level string line between the two. You will need a spirit level in order to achieve this. Where the slope is too great for this to be practical, mark out a string line following the slope, but be aware that your measurement will be slightly longer than your final requirement when calculating the number of panels. In reality, it’s likely to make little or no difference to the number of panels required, but it will affect the width of any in-fill panels required.

If you need to change direction e.g. along two sides of the garden:
Treat the two fence runs separately. First measure one direction, then the next direction and so on. Do this as many times as required and keep the measurements separate.

Step 2: Select your fence panels

Your fence will be a visual feature within your garden, which is why it is essential to select the most appropriate style for your design. If cost is a factor, a traditional lap panel design will always be the most cost-effective option, while closeboard panels also offer a good value option with a bit of design flair.

If it is a design-led style you are after however, there are a range of decorative panels available that combine quality, with on-trend patterns, including our open-slatted Marlow or Malvern panels, or the Montpellier and Tintern panels which offer closed horizontal boards. All of these panels come in a standard 6ft / 1.83m width with varying heights, so for your first calculation, you’ll need to divide your fence length by the appropriate panel size.

For example, if your fence run is 80ft long, you’ll need just over 13 x 6ft panels. This is just your initial calculation however as you’ll need to account for fence posts too.

Step 3: Choose your fence posts

Fence posts are required to support both ends of the panel, which means that you will need one more post for your installation than you have panels. This means if you have five panels on a run, you will need six posts.

Choosing the right size and specification for your fence post is extremely important. Different manufacturers prioritise different things; for example, we prioritise durability and longevity and make sure our posts are made to last. We sell a 75mm square and a 100mm square as our standard posts for domestic fencing, with a range of additional styles and shapes in wood, concrete and metal, to design your perfect installation.

Your posts will account for some of your fence length so for example, if you need 6 posts and you select a 75mm post, this will account for 450mm of your fencing, meaning you need to deduct 45cm/1.48ft from the completed length.

For example, on the same 80ft garden we looked at above, you will need roughly 13 panels. Assuming a single run, this will also mean you will need 14 posts to hold up the panels. A 100mm square post will therefore ​‘take up’ 1400mm (4.59ft) of your calculations, or 140cm, leaving you with 22.98m for fencing. Converting this back into panels it means you’ll need 12.7 panels and 13 posts to complete your installation.

Top tip: if your fence changes direction, you will need to decide about your corner. Traditionally, most installations will use a single post or a specially-designed corner post to support both sides, but for some installs, this will not be possible. If you decide to use two posts, you will need to account for this in your calculations. Sometimes, a simple doodle will help you to visualise what you need.

What happens if my garden isn’t the perfect size?

In the example we used above, an 80ft/24.38m garden will require 12 standard panels and 13 posts, but there will be a ​‘gap’ of roughly 4ft leftover. The easiest way to overcome this challenge is to buy your fence panels from a fencing manufacturer like us, who is able to design and create a bespoke panel that’s the perfect size.
That way you can order the perfect size in-fill panel for the remaining area, along with an additional post to secure it.

As an alternative, some panels will withstand cutting down to size, or you can use a trellis panel as an infill. For a more professional finish, closeboard fencing with feather edge boards allows you to vary timbers to a specific length. What’s more, because the posts and rails are mounted to the back of the fence it means you don’t have to account for them in your calculations.

Don’t forget your gravel boards:

Not every fence installation will include a gravel board, but they are recommended to help increase the longevity of your panels. Gravel boards are typically 150mm in height, and sit beneath the fence panel to protect from the worst of the wet weather, insect attacks, or potential debris which can rot and damage your panels. Just like your fence panels, gravel boards sit between the fence posts, so you will need the same number of gravel boards as you need fence panels.

Top tip: ask us to cut you a hedgehog hole. We’ll add one 135mm wide x 100mm high hole into your gravel boards to allow hedgehogs to roam between gardens. UK hedgehogs are in decline, and part of the reason for this is that they can’t roam far enough at night to feed, mate, and thrive. Fencing is one of the main problems, but a hedgehog hole is all you need to be part of the solution. See the Hedgehog Street website for more information.

Feeling overwhelmed?

If you want to install your own fence but need help understanding the options and quantities, our expert team is happy to help. Please just contact us.

We appreciate that not everyone has the time or desire to install their own fence, which is why we launched our installer network. It’s our network of handpicked, independent fencing installers, who we’ve independently verified. We then certify them to install Walford Timber fencing that’s made to last, giving our clients assurance of a job well done.