Fence and Gate Planning by the Numbers: Panels, Posts and Gate Widths

Fencing quotes are built from numbers: panel widths, post lengths, board heights and gate openings. Getting them right before you order avoids gaps, wasted materials and a gate that will not fit the bins through. This guide sets out the main measurements for a garden boundary and how they add up.

Panels and posts

Most timber fence panels are 6ft wide (about 1.83m) and come in heights from around 2ft up to 6ft or more. To work out how many you need, divide the length of the fence line by the panel width plus the post, and round up.

• Panel width: usually 6ft (1.83m)
• Gravel boards: 6 inches or 1ft high, under the panel
• Post depth: around 2ft in the ground for a 6ft fence
• Example: a 6ft panel on a 1ft gravel board stands 7ft high, so with 2ft below ground it needs a 9ft post

Concrete posts come in a range of lengths for this reason, and a fencing supplier will work the sizes out from your measurements.

Height limits

In England, you can usually put up a fence of up to 2m high without planning permission. The limit drops to 1m where the fence is next to a road used by vehicles, or the footpath beside it. Listed buildings and conservation areas can have extra rules, so check with your council if either applies.

Composite boards

Composite fencing is measured differently. Instead of whole panels, most systems use boards around 1ft high that stack between posts, so the fence can be built to the exact height you want. Manufacturer warranties of 20 years or more are common. Some composite fence panels are available supply only or fully installed, and some boards slot into existing concrete posts.

Gate openings

A gate is only useful if what you need fits through it. Measure the widest thing you will move through the opening, then add some room to spare.

• Side gates: around 3ft (900mm) wide is a common minimum for bins and mowers
• Driveway gates: openings of around 3 to 4m are common, often as a pair
• Ground clearance: enough to clear any slope or step as the gate swings

Weight matters as much as width. Whether you choose wooden, metal or composite gates, the posts and hinges need to be sized for the load. A composite side or driveway gate is heavier than a timber one and is usually hung on steel posts.

Clearing before you build

The final number is the one people forget: how much waste the job will create. Old panels, posts with concrete still attached, hedges and roots can fill several vehicle loads. Pricing for garden waste removal usually depends on volume, so it is worth including in the fencing quote.

Five figures to write down

1. Fence line length: in metres, for each side of the garden.
2. Finished height: panel plus gravel board.
3. Post length: height above ground plus depth below.
4. Gate opening: width and the widest item it must take.
5. Waste volume: roughly how many loads of old fence and garden waste.

With these figures to hand, comparing quotes becomes much simpler. For more on measuring landscaping projects, see our landscapers category.