Position houses to take best advantage of the sun and enhance the client’s expected lifestyle. For maximum solar heat gain, the main living areas or rooms used most often should face true North or be within 20° of true North. However, this has to be balanced against other factors such as views, prevailing winds, privacy, and how rooms will be used.

Other rooms should be positioned to get appropriate levels of sunlight when they’re in use – for example, an east-facing breakfast area will get the day’s first sun and warmth, and a west-facing bedroom will get evening sun.

Factors influencing orientation

The orientation of a building on its site will be influenced by:

• the local climate – is heating or cooling the dominant requirement?
• use of spaces – for living areas an orientation within the range 15°W–20°E of true or 'solar' north is considered best, and 20°W–30°E of true north is considered acceptable.
• latitude and longitude
• relationship to the street
• neighbouring buildings, landforms and vegetation – these can block low-angle sun
• shape of the site, its orientation and its physical characteristics – a north-facing slope has better potential for access to sun and may be suited to higher density development; north/south sites get good sun with less risk of overshadowing
• views
• the need for outdoor living spaces – is an east-west site wide enough to allow a north-facing outdoor area or will it be overshadowed by neighbouring buildings/landforms?
• wind speeds and directions.

 

 

Plan zoning

Plan the spaces within the house according to their need for sun and light in accordance with the client brief, taking account of all activities that occur in and around the house.

East-facing rooms:

• will have good morning light
• can gain heat in the morning all year round
• may need some shading in summer to prevent morning heat gain which may lead to overheating during the day
• can be cool in the late afternoon
• are often suitable for bedrooms, kitchen, and breakfast room.

North-facing rooms:

• will have good daylight most of the day
• can gain heat for most of the day all year
• require horizontal shading to prevent overheating in summer (but allow for winter heating)
• are often suitable for living rooms and dining rooms.

West-facing rooms:

• will have good afternoon daylight
• can overheat in the afternoon for much of the year
• may require vertical shading to prevent excessive overheating and glare in the afternoon
• are often suitable for bedrooms and living areas for those working longer hours – west-facing orientations are not generally considered suitable for kitchens (the heat from dinner preparation coincides with heat and glare from strong afternoon sun)
• provide good direct solar gain for thermal mass heating of living spaces in the evening.

South-facing rooms:

• will have poor daylight for some of the year
• will have little heat gain
• are often suitable for garages, laundries, bathrooms and WCs, workrooms and stairs.

Achieving a balance

Often, it is not possible to obtain the ideal orientation – for example when the view and/or the slope is facing south, or there is a source of noise on the north side, or the view and sun face into strong prevailing winds. Good orientation is about achieving a balance between solar heat gain and other factors such as appropriate levels of daylighting, noise control, indoor/outdoor flow, views, privacy, access, protection from strong winds, and passive ventilation requirements.

It is not possible to be site specific about every site but often compromises will be necessary.

    

  

For your clients

To help your clients understand building orientation, refer them to www.smarterhomes.org.nz/design/orientation.