What the honey bee can teach us about building envelopes |
I attended an excellent presentation yesterday by nationally recognized building scientist, Chris Mathis, a contributing code writing member of the ICC, ASHRAE, NAHB and founder/co-founder of the National Fenestration Rating Council (NFRC). As a hobby Chris is also a bee keeper and very early in the presentation he states that bees can control the temperature of their hive at 92 degrees plus or minus two degrees year round - and this in a local environment where the outside temperature can easly swing 90 or more degrees in the course of a year. Given that a bee hive consists of little more than a wooden shell, honeycomb, wax and the bees themselves I think that's an incredible achievement and I can understand why Chris believes we've got a lot to learn from the 70 million years of experience of the honey bee. We've stated many times that you can have all of the fancy engergy producing and energy conserving products and appliances on the market today but they'll mostly be a poor investment if you do not create an excellent thermal envelope - defining the thermal boundary, so to speak. The energy savings you may be achieving through your geo-thermal heatpump or solar thermal system (both great products in their own right) or similar are probably nullified if your building envelope is "leaking" energy through the wooden studs or tiny air gaps. If you have a traditional stick-built home you're automatically dramatically reducing the effectiveness of your insulation (read more about that here and here). Chris tells us that the honey bee invest 8 times as much time and energy in constructing their thermal envelope - or home - than they do in producing honey. If only the average builder, architect or homeowner took as much care in defining and ensuring the thermal evelope as they did in selecting the kitchen countertops or bathroom fixtures. And while we're at it if only the real estate agents would start off by talking about the energy efficiency and COMFORT advantages of the home before highlighting the wonderful crown molding. By focusing on creating an excellent thermal envelope you can litterally save thousands upon thousands of dollars in less time than the average person typically resells their home (about every 7 years) - this is a "gift" for which the homeowner will be rewarded month after month after month. And this is on top of the benefits of providing a safer, stronger, healthier and more comfortable living environment. It seems that we're finally starting to hold automobile manufacturers more accountable for the gas mileage of the vehicles they produce, yet the average home consumes twice as much energy as the average automobile in the course of a year. I wonder if someday we'll take a stand and start to hold builders accountable to a similar standard. Windows have a rating council (NFRC), why don't walls and roofs? The Energy Star program for homes is a good start, I think, but it's just a start and much more general in nature. Perhaps that's left for future a future blog at another time.... Chris Mathis's fascinating paper on honey bees and how they relate to his studies in building science can be found here. |