In any home, there are two major factors for winter comfort and health: temperature and humidity. A warm, dry home makes the human body feel good, and keeps the immune system strong. Conversely, cold, damp homes do just the opposite. Unfortunately, New Zealand housing is known more for the latter than the former.
It has been easy to forget about the sad state of NZ housing while living in our passive solar, super-insulated villa in Castlecliff. The temperature never dropped below 14 degrees even when a frost carpeted the ground outside, and the relative humidity never rose above 50%. It was easy to maintain a healthy home for our young daughter while paying power bills in the low double digits.
Now that we have shifted, we are confronted with the challenges of living in a cold, damp, draughty home. While the new house and property have huge potential, the living conditions during our first weeks of residence have been a shock to the system. We have had a few mornings of 10 degrees in the lounge, and a relative humidity consistently around 70%. It has been difficult to keep our daughter’s bedroom above 16 degrees overnight, and I suspect the high humidity contributed to her recent illness. I anticipate that our first power bill will be well over a hundred dollars – more than three times dearer than our previous high.
Taking possession in the middle of winter has added an element of urgency to improving the health and comfort of the home. With limited time and budget, I had to prioritize the first best steps to take. Using eco-thrifty thinking and an understanding of how energy and moisture flow through a structure, I focused on a number of low-budget / high-performance strategies.
Shifting from a villa on free-draining sand to a bungalow on clay has meant that rising damp has gone from a non-issue to a huge concern. Up to 40 litres of water vapor enters the average Kiwi home every day from the ground beneath it. A lack of adequate ventilation under our bungalow may mean that we receive even more than that daily dose of damp. While the long-term option for dealing with this is to install polythene sheets as a vapor barrier, a short-term solution to get us through this winter was to break out a piece of Hardie board opposite the access way to allow the wind to cross ventilate.
The next low-budget and high-performance weekend chore I undertook was simply trimming back a vine that was blocking midday sun from entering the lounge. The winter sun is a free heater and the vine was acting like a wall plug switched off. Ultimately, a number of trees to the north will also need to be felled to improve passive solar gain.
With more free heat entering our home, the next important thing to do is to hold onto it as long as possible. As described in last week’s column, that meant topping up our ceiling insulation with wool/fiberglass blankets to an R-value of over 5.0 – nearly twice the requirement of the NZ building code.
But as that extra warmth is held in by our ceiling, it “stacks” downward only to radiate quickly through the single-glazed windows (R-0.15). Windows and glass doors are the weak link in most Kiwi homes, and until we can all afford double-glazing, we endeavor to use curtains to their greatest potential. Just as we layer up with clothing on a cold day, we should cover our windows with a minimum of two layers of fabric and strive for three.
By luck I found some ready-made Roman blinds deeply discounted and bought the lot. It took about 20 minutes to install each blind behind the existing curtains.
One weekend’s work and less than $1,000 has improved the health and comfort of our new home by leaps and bounds. And this is just the beginning.
Coming 7th – 14th September: Adult & Community Eco-Literacy Week.
7th September, 1-2 PM Eco-Design for large properties. 223 No. 2 Line
7th September, 2-3 PM Eco-Design for small properties. 223 No. 2 Line
9th September, 6:00-7:00 PM. Solar Energy. Josephite Retreat Centre, Hillside Terrrace.
10th September, 5-6 PM. Growing vege on sandy soils, TBD
12th September, 5:30-6:30 PM. Best ways to use your heat pump, TBD