When we last were talking we left off asking the question “what are the building things that can make my home energy efficient?” and by that I mean the items and workmanship that will make your home more livable and help to lower your energy costs.
Here is the BIGGIE. Limit and control air flow. Remember your folks always asking “Were you born in a barn? Close the door behind you!” (I hope you didn’t reply under your breath like I may have, “No, I was born in a hospital where the doors closed automatically.” Not a good reply.)
It’s obvious that if you have a big hole in your wall things aren’t going to look good on you next utility bill. Less obvious are the small leaks that you can’t see or even feel; the hairline cracks hidden by the flooring and base boards between the bottom plate (this is the 2×6 at the bottom of your wall that is on top of the floor decking) and the decking; the electrical boxes that are fed with cold air that travels via the holes that the wires feed through; and plumbing pipe penetrations in floors and top plates into crawl space and the attic that also let air in (along with creepy crawlies in extreme cases). The good news is that for new homes the code requires that the air infiltration be controlled by sealing (caulking or foaming) the joint between the wall and floor and the holes drilled in exterior walls for the wires and pipes. If you have conscientious workers this should be taken care of in new home construction.
If you have a forced air HVAC (heating ventilation air conditioning) system (as opposed to ductless systems that are now becoming popular), there is the issue of not getting the conditioned air to where it should go. Recently, at the Pacific Coast Builders Conference, they stated that as much as 60% (a figure that I question) of the conditioned air “leaked” out of the duct work. While I believe that number is from rare and extreme cases there is no doubt that there has been significant leakage with older systems. Then, let’s add to that the unfortunate reality that not all workers take the same amount of care in doing their job while putting the duct work in place. To make sure that your system is the most efficient the duct work needs to be sealed and verified with a test. So if you want to know that you have a well built system the best way to confirm is with duct pressure testing (which we now do).
As to the air leakage in the duct work there is no current code for that problem but it will be changing in a few years.
SMALL COMMERCIAL – COME BY OUR MODEL AND FIND OUT HOW WE SEAL OUR ENERGY STAR DUCT WORK
Now that we have addressed making the home “tight” we need to address another concern (no good deed goes unpunished). Your home is nice and tight and cozy so you keep the windows and doors closed (see above for the big hole problem) but in doing so you are now trapping moisture and gases in your home. The key is to control when and where you introduce fresh air. We do that, and have been for over 20 years, with a whole house ventilation system. The short description is: exhaust fan, power damper, timer and all tied into the HVAC. To see and learn more see small commercial above (sorry but I just can’t keep away from some promotion).
So that kinda covers the biggest issue. The next is insulation and here more is better, up to a point, and then diminishing return kicks in. But in general terms flat ceilings are better than sloped. In fact, the proposed new code will severely limit and restrict vaulted ceilings. But to repeat from an earlier post, you want a home you can enjoy which includes the aesthetic aspect, so know that a vaulted ceiling can be done if special steps are taken.
The next item is the windows. Most windows that meet the current code are very good. We’re talking about the energy efficiency here and not the total carbon footprint or the life cycle which brings into play vinyl vs. wood vs. metal but that is for another day and another cost/benefit discussion. Just make sure that at a minimum you have low-E, argon, and double pane (sometimes called Thermopane) windows.
Now we get to “things” like tankless water heaters, energy-recovery and heat-recovery ventilators, induction cook tops, and LED lights. For the moment let’s save those and we will get to some of them next time.
May you find the home you envision.