The way we build a home is constantly changing. New codes come out every three years, new technology is evolving faster than I can keep up, and new materials help to make building a home easier. (Sometimes!) So, what are we striving for? What’s the end game? Let me look into my crystal ball and I’ll tell you where we are heading. Ok, I’ll give you my best guess.
I’m convinced that the goal of the evolving energy code is to have all new homes built to be Zero Energy or Zero Energy Ready. That is where a home produces as much energy as is uses. How do we accomplish Zero Energy? By building a very energy efficient home and add energy production, such as PV solar. Read about the basics of Zero Energy here.
Solar photovoltaic systems will become more common in residential neighborhoods. These systems will be paired with batteries for load control management, which will be controlled by your electricity provider. Electricity providers will become more involved in the technology as there business plan is forced to evolves because of the increase in solar use. Increased solar use is already effecting some electricity providers bottom line. I think at some point these providers will be forced to imbrace this technology and evolve to keep their businesses alive. One way for this to happen is to use batteries to help control the peak loads on the electric grid which will help to lower the amount of power an electricity provider needs to purchase during the times of high electricity use, when electricity costs the most. We may also see these electricity companies become retail sources of PV systems. Part of their income will be from selling, installing, renting or leasing the systems used to produce some of the power they sell.
Devices inside your home will be controlled (turned on and off) by your electricity provider. Ok, that is already happening. But more devices will be available for control in the future. The power company I work with conducting energy assessments has programs where they control electric heat sources, water heaters, air conditioners, and in some cases, even the whole building. (These buildings have large generator sets sized to supply the entire building with power.) Future battery technology could make this whole house control possible without a noisy generator.
Electricity will become the main source of heat (and cooling) for most new homes built in the future, to be specific, the air source heat pump will be that source. The advancement in ASHP technology has made huge improvements over the past decade, these improvements will continue which will make electricity more competitive as a heat source. I believe this change is coming, but is a ways out. We in North America have a huge supply of natural gas which is suppressing the cost. This low cost of heating with natural gas will slow the transition to electric.
Homeowners will easily be able to monitor the energy use of their home. Power companies will allow their customers to log in and view electricity usage in real time. New electrical service panels will have smart breaker technology that will track usage for each breaker or circuit in the home. Devices and appliances within the home will connect through WiFi so a homeowner can monitor and control the equipment. Much of this technology is already available, technology advancements will continue to improve.
Building codes will continue to make new houses tighter. I wouldn’t be surprised to see 1.5 air changes per hour at 50 Pascals code requirement. (Current codes are 3 air changes per hour at 50 Pascals.) This will take place over several code cycles.
Balanced mechanical ventilation will be required, either by heat recovery ventilation (HRV) or energy recovery ventilation (ERV). This is already a code requirement in Minnesota. Read more about HRV balanced mechanical ventilation here.
New houses will be “commissioned” before they are allowed to be occupied. Some commissioning is already required in some areas, such as blower door testing. Other testing will be required to confirm the home’s performance. HVAC testing to assure proper air and heat flow to rooms, bath fan testing for proper CFM ventilation rates, and testing of mechanical ventilations systems to be sure they are properly balanced will all be required before an occupancy certificate is issued. Testing plumbing systems for water conservation may also be required in some parts of the country.
All real estate transactions involving the sale of a home will require and energy audit and some form of rating. Imagine purchasing a home and having an idea of how much energy it uses. Right now it’s kind of like purchasing a car without taking it for a test drive. Required home testing will change that. Watch a video about this here.
Rain screen code requirements become a reality. Another topic I plan on writing a full blog on. A rain screen is a gap behind the siding to allow moisture to drain. A ventilated rain screen is where moisture can drain and air can move freely behind the cladding to promote drying. A rain screen will help the finish of the siding last longer, keep the sheeting, (OSB, plywood, Zip) dry, and improve outward drying of the wall assembly.
Exterior insulation will be required by code. Some builders are already adding exterior insulation, but it’s usage is not wide spread. The 2018 energy code has an exterior insulation requirement. My state of Minnesota likes to rewrite the energy code. Pressure from builders and home builder associations may strike the exterior insulation requirement from our next code cycle, which will be in 2021. Future codes will make it a requirement.
That’s it for my predictions for now. There may be more in the future.