WORDS Nadine Botha PHOTO Jan Ras
Jürgen Kieslich is a Cape Town-based architect who bought a small block of flats in Woodstock and set about greening its energy consumption. A few years on, he realised that not everything is as cost- and planet-efficient as the green-washing marketers would have us think. He shared 10 lessons with us.
1. Start with the basics
Insulation is the cheapest way to moderate the temperature in your home, bringing down your electricity bill. Insulate the roof, walls and floor – over 40% of a home’s heat is lost through uninsulated walls and roofs. “Once it’s done, you never need to think about it again,” says Jürgen. Windows contribute another 20% or more to heat loss, and here double-glazing is the way to go for insulation. “Even the smallest electric heat source would work six times better with double-glazing and sealed windows,” Jürgen points out. It may be expensive but they also shield against blazing sunlight in summer and act as a significant sound buffer.
2. Choose the tried and tested
Jürgen installed a brand-new plastic plumbing system that promised to be über-green. It delivered all it had promised but when it came to maintenance a few years later, he discovered the system had failed to take off in South Africa and no one knew how to fix it. Work with technology, products and companies that have been around the block.
3. Keep it simple
Although sometimes one has to take a leap of faith on new products, Jürgen advises that the simpler the solution, the more likely it is to work. “If it sounds like it is adding another layer of complication – this system is needed to supervise that system needed to measure this – then start worrying. It will require maintenance and solid technical acumen, which will cost you if you can’t do it yourself.”
4. The hot water solution
“Hot water is the biggest place to save on electricity,” according to Jürgen. However, he has learnt that solar water heaters don’t work that well in apartment blocks or anywhere where the panels are too far away from the water tank. If you can’t install the panels and the tank in close proximity to one another (and as soon as you receive advice that you will also need an extra this and that – see lesson 3) rather go for a hot water pump. Jürgen observed a 30 to 40% electricity saving all-year round with the pump and it costs one third of the price of a solar water heater.
5. Heat from below
Once you have a cost-effective source of hot water, Jürgen can’t stop singing the praises of water-based under-floor heating – especially if you’re going for those trendy but freezing concrete floors. The system could reduce your heating bill by up to 60%. It brings the floor up to about 23°C – taking the edge off the chill without making the floor hot. Electric under-floor heating, on the other hand, is electricity intensive. It causes air movement that stirs up dust and is wasteful because the hot air ends up at the ceiling. “It’s like the difference between a gas and an electric oven. Water-based under-floor heating is just moister and cooler,” says Jürgen.
6. Green the pool
Like maintaining a garden, rather than a chemistry experiment, natural swimming pools, or eco pools, are an environmentally friendly option. Yes, swimming is the last thing on your mind in the cold months. But, says Jürgen, because eco pools need three to six months for the plants to settle and algae to clear, autumn or winter is the best time to install them. Eco pools work by using plants and gravel as a filter, and the silky quality of the water has to be experienced to be believed. Traditionally a challenge for small spaces, Jürgen is currently experimenting with a vertical garden (above) to filter the pool water in his courtyard.
7. Plant a tree or three
Use your garden and surroundings to control sunlight by means of strategically planted trees. At the apartment block, Jürgen planted a row of poplar trees on the west side, which shielded the apartments from sun in summer by acting as a massive shutter, but had the opposite effect in winter when they lost their leaves.
8. Size matters
The larger the house, the more materials, maintenance, heating and cleaning are required, and none of this is getting any cheaper. “I’m trying to talk people into making smaller homes,” Jürgen enthuses. “Rather make the common room larger and keep the other rooms small. Make multifunctional rooms: do you really need a separate lounge, TV room or playroom?”
9. Rain farming
Unfortunately, Jürgen admits, rainwater harvesting doesn’t work that well in Cape Town unless you have a massive cheap storage solution for winter and a tiny garden to water in summer. However in summer rainfall areas such as Johannesburg, it’s an absolute must.
10. What about solar?
If you’ve down-sized your home and have the cash, then go solar. However, Jürgen regrets that solar just doesn’t cope well with high electricity usage. “At most, a panel can cope with a fridge, some computers, light bulbs, and the charging of cellphones and cameras,” he says. “As soon as you add a washing machine, tumble dryer, dishwasher, pool pump and television, you have to consciously make a lifestyle decision about how much you really need these things,” he concludes.