In this journal entry we delve into the secrets of a warm home – without the power bill. A homes performance or how energy efficient it is is critical to achieving this without declaring bankruptcy. The order you do things is just as critical as what you do too. According to Consumer NZ we must “reduce damp, insulate and draught-proof, then heat.” We know the problem in New Zealand tends to be cold and/or damp houses. However, the answer is not to simply turn up the heaters or get more of them. The solution lies in identifying the cause of the dampness and coldness and treating those causes accordingly. We have focused on four causes and some practical solutions below.
1. Draught-proof areas. It’s all about a tight fit. Windows need to fit perfectly in the joinery. Curtains need to go all the way to the top and bottom of the window and the heavier the better. If doors don’t fit snugly in the frame look at using draught-stopping tape or seals and those snake looking things at the bottom of the door. Window maintenance companies offer rubber seals for joinery units. Also another big baddie for draughts is your ceiling access hatch or man-hole. It acts like a chimney flu, sucking warm air out. If nothing else, draughtstop that. Now is a good time to consider removing all the down lights as they also effectively act like little chimneys expelling your precious warm air. Replace with air-tight LED’s which can/should have insulation covering them in the ceiling – see below.
2. Improve insulation. According to Homestar “the most important place is the ceiling. Get up there and check your insulation. It should be at least 12 cm thick with no gaps, folds or tucks.” As a Homestar certified practice we totally agree with this statement however this is just the beginning to a warmer more comfortable home. Get as much in the ceiling as you can. Lay the second layer of insulation perpendicular across chords or ceiling joists to eliminate thermal bridging. Changing to LED’s will allow insulation to cover lights which further tightens the thermal envelope. If insulating timber floors look at faced-insulation which deals with wind-wash better. Better still insulate underneath joists to create a still airspace for ultimate insulation and no thermal bridging. If you have a concrete slab look at insulating the edges. In retrofit situations there are semi-prefinsihed boards like Marmox or similar to stop heat bleeding from the slab edge. See our Journal post on Thermal Mass for more information.
3. Heat the right way. Say no to unflued gas heaters they create a lot of moisture in your home leading to damp mold and mildew and are actually the most expensive heating option. There is nothing better than a fire on a wet winters day. Dry firewood throws out a lot more heat than wet wood so be prepared and get the wood in your shed drying a year before you need it. If you don’t have a fire, heat pumps are the next cheapest and healthiest way to heat a home when set at a temperate 18-20 degrees. They are not designed to be cranked up to 30 degrees to blast-heat a room. Use timers and thermostats on all heating appliances and only turn them on when you are actually home. When looking to install new, consider a true heat recovery ventilation system (not to be confused with HRV or DVS) which brings in new fresh air through a heat exchanger. These units remove allergens and moisture from your home increasing air-quality. Europe has been doing this for decades and New Zealand is slowly catching on.
4. Cooking and washing (clothes, the dishes and yourself) are typically the two biggest causes of dampness in a home. Not including homes with weather-tightness issues but we won’t go there. Always dry clothes outside, drying inside creates damp air leading to condensation and mold. Also a clothes drier is expensive costing around $1 a load depending on the make and model. Extractor fans should always be used when showering and cooking to remove moisture also. The key here is to make sure they are vented externally. Ideally they are wired in and include a timer ensuring they run for ten minutes following use. It seems counter-intuitive but opening a window when cooking or washing helps remove moisture from a space. Regularly airing your home, including wardrobes and other closed spaces is essential to remove dampness. When a home is damp it is harder to heat and near impossible to make toasty!
There are tonnes of other ways you can warm up your home over winter but if we went on much more you’d be bored. We will say one more thing though, just because we love natural flooring. Whip out a rug in winter to place on hard surfaces. Then you can enjoy beautiful timber or concrete floors most of the year and when the cold snap comes just roll out a rug.
If you or someone you know is looking to build there is a way to avoid having to retrofit heating or insulation solutions to achieve a warm and healthy home – engaging the right designer at the start. The team at Adam Taylor ARCHITECTURE are certified Homestar and Greenstar Practitioners, members of the New Zealand Green Building Council and are leading the way in performance housing in the Bay of Plenty and arguable New Zealand. Sustainable, energy efficient designs zeroing in on passive heating, insulation, glazing, solar heating, and more so your home is the best place to be.