Designing the Optimal Solar Orientation of Your Villa in Spain

We include this in all our designs so what does it actually mean?

Design for Optimal Solar Orientation
Design for Optimal Solar Orientation

The angle at which the sun’s rays hit your home varies during the day and from season to season. It can have a big effect on your heating / cooling costs and on the overall sense of comfort your home gives you. It should be studied in conjunction with the layout and function of the rooms and outside spaces, the window placement, the insulation / thermal mass, and heating and cooling systems. Getting this right is a big part of designing a comfortable energy efficient home.

 

 

Inland or Coastal Spain

Many designs in northern Europe place the primary occupied rooms for maximum solar gain in the winter to reduce heating costs. However in southern Spain you may be more interested in avoiding solar gains in the summer to minimise the chance of overheating in the summer. The climate can vary enormously in Spain. Inland Spain is quite different to coastal Spain. It can be very cold in the winter in inland Spain. So the optimal solar orientation may be quite different depending on the exact location.

Lifestyle

Shading and spaces for outside living are likely to be an important part of your design. The depth of the shading is important and may vary according to your lifestyle and the particular advantages of the site. You may not want to shade so deeply you can’t enjoy the view from inside for example. You may prefer a breakfast area which captures the morning sun before the atmosphere and the building has warmed up. You may want a place for sitting out in the winter sun as well as a winter suntrap inside the house. The sun’s angles are very different in the winter than the summer and a careful study is needed before the optimal solution can be found.

Any views available will also influence the orientation and layout of the building as will trees, mountains, and neighbours. Trees and vegetation may be planting to funnel wind or provide shade as necessary. Deciduous vegetation with foliage that provides shade in the summer that disappears in the winter may be appropriate in some places.

Sleeping comfort may be a primary consideration.

Renewable Energy Sources

If you are sourcing the sun for renewable energy, and solar hot water is standard in our houses, then the placement of the panels and the angles at which they are placed may from part of the design.

Direction and intensity of the wind: cooling breezes

The prevailing wind direction is also important. You may want a cool breeze available in the summer evenings in a place for sitting out. You may also want to shelter against the wind if your site is exposed. You may want cross ventilation inside your home as part of passive cooling design.  High windows can act as heat chimneys releasing the heat in the summer.

Careful Research

We produce plans that illustrate the exact angle of the sun at any time of any day in the year and how it varies through the year

We also take into account:

  • Temperature ranges seasonal and diurnal
  • Humidity ranges
  • The direction of cool breezes, hot, cold and wet winds
  • Seasonal characteristics
  • Local geographical features and adjacent buildings on the micro climate

Good orientation, combined with other energy efficiency features, can reduce or even eliminate the need for auxiliary heating and cooling, resulting in lower energy bills, reduced greenhouse gas emissions and improved comfort. It takes account of summer and winter variations in the sun’s path as well as the direction and type of winds, such as cooling breezes.

 

John Wolfendale Chartered Surveyor Granada
John Wolfendale Chartered Surveyor Granada

 

Author: John Wolfendale

Bio: John is a founder of Eco Vida Homes and is passionate about bringing modern design and construction practices to Spain. He believes a home which is warm in winter and cool in summer is largely a matter of design and selective use of materials.  He is British and a Chartered Surveyor with over 22 years experience living and working in Spain.