Garden Steps Uneven And Unsafe

What's happening?

People fall on garden steps because of inconsistency rather than height. The body learns a riser height in the first two steps and then stops looking, so one step that is 20mm different from its neighbours is what trips someone — which is why an original flight that has settled unevenly is more dangerous than a steep flight that is uniform. Add the outdoor variables and the risk climbs: a smooth stone tread grows algae and turns slippery in wet weather, a settled step tips forward and sheds water onto the next tread down, and unlit garden steps get used in the dark. Approved Document K of the Building Regulations covers protection from falling and the principles behind step geometry and guarding; garden steps sit outside its strict scope but the geometry that makes a stair safe is the same outdoors.

What usually causes it?

• Individual steps settling as the ground or the fill beneath them compacts, leaving inconsistent risers
• A flight built with unequal risers from the start, to make the levels work out at the top and bottom
• Treads laid flat or falling backwards, so water sits on them and freezes rather than running off
• Algae, moss or lichen on a smooth tread making a step slippery in wet weather
• Frost damage spalling the face of concrete or stone treads and rounding the front edge
• The bottom step undermined by surface water washing out the sub-base
• No handrail on a long or steep flight, no guarding at an open side with a drop, and no lighting on a route used after dark

When should you call a landscaper?

Call a landscaper when risers differ across the flight, when a step rocks or has settled, or when someone has already stumbled on them. Bring it forward if the steps are the main access to the house, if there is an unguarded drop alongside them, or if a household member is at higher risk of falling. If the flight also forms part of a retaining structure that is moving, deal with the retaining first — rebuilding steps onto a wall that is still going is wasted work.

What will the landscaper actually do?

• Measure every riser and going in the flight and work out a consistent set that fits the total rise
• Excavate and establish why the settled steps moved — fill, washout or an inadequate base
• Rebuild on a properly compacted sub-base and concrete foundation so the treads cannot settle again
• Set treads with a slight forward fall and a defined nosing so water sheds and the edge reads clearly
• Use a slip-resistant surface finish, or add anti-slip inserts where the existing material is smooth
• Fit a handrail on a long or steep flight, guarding at any open side with a drop, and low-level lighting where the steps are used after dark