Wire balustrades for decks, balconies and stairs

A wire balustrade keeps the view open from a raised deck, a balcony or a stair. It still has to stop people falling, small children included.

This page sets out what the building guidance for England asks of any guarding, and where wire infill needs extra thought. The guidance is Approved Document K, which the government publishes for the Building Regulations.

When an edge needs guarding

In a house, the guidance asks for guarding that stops people falling more than 600mm. On a stair, that means guarding along the sides of flights and landings wherever the drop is more than 600mm.

It also asks for guarding at the edge of a floor, balcony, roof or any other place people can reach, wherever it is reasonably needed for safety. The guarding can be a wall, a parapet or a balustrade.

How high the guarding should be

For a single family home, the guidance gives 900mm for stairs, landings, ramps and the edges of internal floors. External balconies and the edges of roofs need 1100mm. That includes Juliet balconies.

Flats, offices, shops and public buildings follow a different table. In most of their locations the height is 1100mm, with 900mm along stair flights.

Gaps, wires and climbing

Some buildings may be used by children under five. There, the guidance asks for two things. A 100mm sphere should not pass through any opening in the guarding. And small children should not be able to climb it easily.

For climbing, the guidance gives one plain instruction. Avoid horizontal rails.

Many wire balustrades run their wires horizontally. Before you choose that layout for a home where small children live or visit, ask your building control body how they view it. You can ask them about a vertical layout at the same time.

Wires can also flex. Ask the supplier how the gaps stay under 100mm when someone pushes against them.

Strength and design

Guarding has to resist at least the loads set out in BS EN 1991-1-1, with its UK National Annex and PD 6688-1-1. For the design of barriers and infill panels, Approved Document K points to BS 6180.

The British Standards Institution (BSI) publishes BS 6180. Its 2011 edition covers the height, structure and strength of barriers. It includes a table of minimum loads for balustrades and rules on how far a barrier may bend.

Planning permission and building control

In England, a garden deck is usually permitted development when it is no more than 30cm above the ground. It must also cover no more than half the garden, together with other extensions and outbuildings, and it cannot sit in front of the house. Listed buildings, flats and some protected areas have tighter rules.