Retrospective #9: Draft Avoidance

After writing about debt aversion and monster mortgage avoidance last Saturday morning, I was interested to hear on the radio that very afternoon about the record number of mortagee sales in New Zealand during the first quarter of the year. My heart goes out to those families losing their homes. Part of the motivation for writing this column voluntarily for the Chronicle is that it might help some families save money and avoid some of the dangers of debt. 

Last week I also reviewed some of the low-hanging fruit (shortest payback period) of energy savings that we have plucked in our eco-thrifty renovation. Those included: window battens (insulation), plastic window film (insulation), and, compact fluorescent light bulbs (electricity savings). These three examples are not exclusive to renovation, nor are they exclusive to home ownership. Nor do they even take much skill, or a building consent for that matter. Anyone in Wanganui – owner or renter, young or old, craftsman or klutz – could install these today and start reaping savings tomorrow. 

Last week I also identified some of the medium-hanging fruit such as solar hot water, insulating and adding north-facing glazing. Be aware, some of these require consent and a licensed builder. And high-hanging fruit…to be quite honest, we don't really worry about those which have payback period over 15 years. Solar electricity, for example, has a payback period of between 20 and 30 years. Together, these investments in energy savings have paid off handsomely. As our most recent power bill shows (see photo), we are now part of the 99...Cent! 

But our Occupy Arawa Place movement involves more than passive solar design. This week and next I’ll share three more of the lowest-hanging fruit that save energy and money. These are examples of the fourth of our seven design principles: draft-proofing. 

Reducing airflow through a home is not specific to passive solar design, but it is key to the goal of a warm, dry, low-energy home. Drafts account for 6% to 9% of heat loss from residential dwellings, and old villas like ours are notoriously drafty. A visitor to one of our open homes early in the renovation process exclaimed: “I’ve been in this house before. I babysat here once. This is the coldest house in New Zealand!” Having examined nearly all of the nooks and crannies in this old villa, I suspect her Antarctic experience was partly due to drafts. An easy way to find drafts is by burning incense and holding it close to doors and windows. The moving smoke will indicate where cold air in entering your home. Then plug those gaps! We’ve addressed draft-proofing in these ways: foam window and door seal; draft blockers (home-made); and, draft excluders (purchased).

The first of these is pretty straightforward. Window and door seal is available from all the usual suspects, and is advertised by them this time of year in newspaper circulars. (By the way, newspaper circulars also make an excellent internal heat source for a home when inserted into a wood burner.) Foam window and door seal is cheap as chips and easy to install. Go get some, but make sure that all surfaces are clean and dry before applying it! This product will help reduce drafts around windows and does the same for the top and sides of door frames. But the bottom of exterior doors needs something else. 

What I call a “draft blocker” some may call a “draft dodger,” but that term has a bad connotation in the USA. Whatever you call it, most people are familiar with this fabric tube (like a long sock) full of sand or beans or whatever that is placed against the bottom of an exterior door. But here's the thing: most draft dodgers have a round edge but the bottom of a door is at a right angle to the floor. That means there will be a gap in this supposed gap filler (round peg – square hole scenario). So my version is different in that it has a square edge. It is one of the easiest eco-thrifty things you can do.Here's how to make one: cut a 45mm x 45mm piece of wood 5 mm longer than my door. Then wrap an old towel around it. Lastly, tie off the ends with fabric strips like a sausage or Tootsie Roll. This gives a tighter seal at the bottom of the door and can be made cheaply and easily. These are even helpful to use with aluminum doors that may have no drafts, but conduct heat outside through the metal. The draft blocker slows the thermal bridging of heat through the aluminum. Remember, every little bit helps especially when it involves low investment and high performance. 

Peace, Estwing