Q: We’re looking to build a new outdoor entertaining area applying passive solar techniques. We want to make sure that it doesn’t get too hot in summer – would a whirlybird in the roof help? We also like lots of winter sun for warmth, but also want the area to be covered and dry. Any design ideas or advice?
A: Here are a few design tips to help you design an outdoor living area that is cool in summer, and warm and dry in winter:
- If you have an existing patio or pergola, first see if it’s possible to modify or adapt this structure to suit your needs. This may help to minimise the amount you need to spend, and also reduce the amount of construction waste that ends up in landfill. For example, replacing the roof sheeting may allow more winter light, while adding correctly angled louvres to the existing rafters can help to block out summer sun.
- If the outdoor structure does not comply with current building codes, or has been damaged by rust or termites, demolition is probably the better way to go. Try and salvage or give away any useable building materials and/or use a waste contractor that will recycle the demolition materials, such as Instant Waste Management.
- Try and locate your new outdoor area so that it has good access to northern sun – sun from this direction is easiest to shade in summer, while also provides warmth and natural light in winter (see solar pergolas later). If your new outdoor area is connected to or adjacent to living areas inside your home, try to make sure you don’t block northern winter sun from entering your home – this can make your home harder to keep warm in winter. Also have a think about how your new patio or pergola will integrate with the rest of your garden and outdoor space. You might want to engage a landscape architect or designer to plan and design your garden in conjunction with your new outdoor area, to help make the best use of your outdoor space.
- If you want an outdoor space that is more useable in summer and fully shaded, consider an opaque, insulated roof such as Solarspan
- Companies such as Stratco can also custom manufacture pergolas and patios to suit your needs
- If you’re after something that will be sunny in winter but provides protection from the rain, a covered solar pergola with fixed louvre blades is the alternative. The trick is to make sure the louvre blades are correctly angled and spaced to block summer sun, while allowing winter sun. In Perth, the optimum angle is around 34 degrees – it will vary for other towns and cities. Here is one Perth company that specifically mentions solar pergolas in their website
- To help ensure your covered outdoor area doesn’t overheat, keep the sides open to allow for natural and cross ventilation. If you want the option to be able to enclose or protect from the wind, consider adding roll down blinds. However try to avoid blinds made from vinyl or PVC, as this is not a very healthy building material.
- Adding a ceiling fan is the best way to keep things cool; unfortunately whirlybirds don’t really work in this situation (they are better for enclosed roof spaces). There are a number of beautifully designed fans available these days. Make sure you have sufficient height clearance for the fan!
- There are companies that manufacture and install outdoor area roof systems with motorised louvres that can open and close to control the amount of sun and keep out the weather. These systems can provide a lot of flexibility with how you can use your outdoor space, however they can be very expensive, and a bit temperamental (such as closing automatically even when you want them to stay open). While they do a pretty good job at keeping out the rain, you will still get some leaking water, particularly during heavy downpours.
- You may also want to check out the Australian Government’s Your Home website, which contains valuable design advice on passive design and shading
Note: No financial incentives or kickbacks are received for the websites and links contained in this post. I don’t specifically endorse or recommend these companies or products; make your own informed decision about using them!