Autumn's almost here and winter's around the corner – now’s the time to prepare your home for the cold.
We’re heading for autumn, and that means winter isn’t far behind - you know, dry and icy winds for those of us who live inland, wet and icy for the people of the South (Cape Town and such).
For yourself, you’re probably thinking about getting your jackets and long-Johns out of storage and cleaning them up, ready for when the first cold snap snaps its nasty little fingers - but what about your home? How’re you going to keep your house toasty (especially now that our national electricity supplier isn’t behaving all that well?)
“A house will typically lose as much as 34 or 35% of its energy through its ceiling,” said Kevin Els, a principal at Gauteng’s Evolve Architects.
He said that the South Africa’s National Building Regulations, which came into effect in 2011, make provision for the environmental sustainability and energy efficiency of new buildings (see ‘The application of the National Building Regulations’), but that most older buildings - which would have been designed when energy was cheaper and of less immediate concern than it is now - would probably benefit from the installation of additional insulation.
DIY OR CONTRACTOR?
“Getting into the roof and installing insulation above the ceiling can be a difficult and unpleasant job - and some of the available materials require careful handling - so it’s very often best to leave it to the professionals,” said Kevin.
The efficiency of insulation materials is described on a sliding scale of R-values - thickness divided by thermal conductivity (or K-value) - with the most effective insulators receiving the higher numbers. (See sansrvalues.co.za for R-values of many of the products on the local market.)
Kevin said that the most commonly available insulators which are cost-effective for home-owners include:
Recycled PET bottles (Isotherm for example, R-value 2.39): “Basically cool drink bottles that are spun into a kind of blanket that’s easy and safe for DIY;”
Glass fibre (Aerolite for example - R-value 3.1): “Inflammable and also easy to install - but because of the nature of the material, it’s best to have the work done by a contractor who’s properly trained and equipped for it;”
Mineral wool (R-value 3.1): “A felt-like product that’s spun from a mixture of molten rock and slag;”
Cellulose (R-value 3.7): “An efficient, environmentally-friendly product that’s made from recycled newsprint and cardboard, and that’s usually pumped into the ceiling cavity quickly and easily by the contractor;” and
Polyurethane foam (R-value 6.3): “This is that brownish-yellow foam that hardens on contact with the air. It’s one of the best insulators you can get - but it’s also one of the most expensive.”
“Getting ready for winter isn’t only about insulating properly, it’s also about minimising your demands on the grid,” said Kevin.
Can you perhaps get by without certain appliances? And how can you substitute for them simply and conveniently?
“You could build your geyser into a cupboard to create a warm drying area so that you can lose the tumble-dryer - like they’ve done in Europe for years.
“Or if you have the space, you could build a fibre-glass-clad lean-to over your washing line to trap the heat of the sun.” (And, if you’re in the Cape, have the added convenience of being able to leave your laundry on the line overnight - without it getting a second rinsing from rain or heavy dew.)
“With a bit of thought and some research, making your home as energy efficient as possible will pay off quickly - both because it’ll be more comfortable to live in, and because it’ll save you money in the long run,” said Kevin.