Outdoor spaces that stand up to the south-easter

Summer in Cape Town means long, light evenings, and it also means the south-easter. The “Cape Doctor” clears the air but can make a beautiful terrace unusable for days at a time. With some thought, outdoor spaces can be designed so they work even when the wind blows.

Know your wind

The south-easter blows mostly from late spring to the end of summer. How it affects your home depends on the site: it accelerates down the slopes of Table Mountain and the Twelve Apostles, gusts around buildings and funnels down valleys. Some suburbs and even some corners of a garden are much more sheltered than others.

Before designing, spend time on the site on a windy day. Note where the wind comes from, where it gusts and where it is calm.

Use the house as a shelter

The best windbreak is often the house itself. An outdoor living space on the sheltered side of the house, or in a courtyard enclosed on three sides, can be calm when the rest of the garden is blowing. On many Cape Town properties, the north-west side is sheltered from the south-easter but exposed to winter weather from the north-west. A covered terrace there can work year-round.

Screens and walls

• Solid walls stop the wind directly behind them but create turbulence beyond. They work best close to the seating area.
• Permeable screens, such as timber slats, perforated metal or planted trellises, slow the wind over a larger area and cause less turbulence. A screen with some openness is often more effective than a solid wall.
• Glass screens keep the view while blocking wind. They must be properly designed for the wind loads, with safety glass and secure fixings.

Pergolas, roofs and covers

Pergolas, retractable awnings and shade sails all have to handle strong winds:

• Pergolas need proper footings and fixings designed for wind uplift
• Retractable awnings must be retracted in strong wind, ideally with automatic wind sensors
• Shade sails need strong posts and fixings, and should be taken down in storms

Fixed roofs with slatted or louvred ceilings give shade without catching the wind like a sail.

Planting

Hedges and dense planting make excellent windbreaks, filtering the wind instead of blocking it. Choose plants that tolerate wind and salt, such as many indigenous coastal species. A local landscaper will know what thrives in your area.

Pools

Wind cools a swimming pool and blows debris into it. A pool in a sheltered position is warmer and cleaner. Glass pool fencing can double as a windbreak (see our post on adding a pool).

Materials

• Furniture should be heavy or easy to store
• Fixings should be stainless steel, particularly near the sea
• Outdoor fireplaces and braais should be positioned with the prevailing wind in mind, so smoke blows away from the seating

Design it once

Outdoor spaces are often an afterthought, added after the house is finished. Designing them with the building means walls, roofs and screens can be properly founded, drained and detailed. If you are planning an outdoor space, talk to us.