Today, retrofitting your property has taken on a new purpose and is no longer thought of as a simple remodeling done only for aesthetic reasons. The focus instead has turned to a building’s overall energy performance for the purpose of lowering operating costs, increasing occupant comfort, and minimizing the carbon footprint.
Depending on the type of building, reasons to undertake an energy retrofit project differ. For a homeowner, occupant comfort is usually the main motivator with energy savings being second but for a building owner, it is the opposite. Upgrading inefficient energy-sucking systems translates into lower operating costs which is the main objective for large buildings. Another reason to undertake an energy retrofit applies to everyone which is the goal of reducing CO2 emissions that are steadily on the rise.
Why is an Energy Retrofit Important?
First, let’s look at the carbon footprint of the building sector and why an energy retrofit is important.
The International Energy Agency (IEA) published in a Global Status Report in 2017, that over the next 40 years (now 37), the global construction industry is expected to add approximately 230 billion square meters of new construction. They compare this to being equivalent to adding the size of Paris to the planet every single week. It is a shocking amount of growth that needs to be considered when predicting future levels of CO2 that the construction industry will contribute to the atmosphere in years to come and when devising a global reduction strategy.
Currently, buildings account for more than 40% of global energy consumed and are responsible for approximately one-third of all greenhouse gas emissions. Adding the size of Paris in square footage every week will have a significant effect on our efforts to lower global emissions. For example, experts have compared the current rate of reduction for CO2 emissions within the buildings sector, to what new construction will add to these emissions. Published in the same report from the IEA, it is estimated that CO2 emissions within the buildings sector have improved at an average rate of 1.5% per m2 due to current retrofitting efforts and updated building codes.
However, with the global floor area continuing to grow at a rate of about 2.3% per annum, it is easy to conclude that CO2 emissions will continue to increase unless we can get to a net-zero outcome by implementing other strategies. For example, the report also mentioned that by implementing smart controls and connected devices, energy consumption within the building sector could be reduced by as much as 10% which indicates that we could greatly reduce CO2 emissions from the building sector by implementing one simple measure. Therefore, building automation is clearly a retrofit upgrade that should be considered seriously and, in my opinion, possibly made mandatory.
Your take-away from this is likely to be that retrofitting large buildings within the commercial and institutional sector would have the greatest impact and it may also leave you thinking that retrofitting your own small residential square footage will hardly make a difference. However, as shown in the numbers above, the cumulative effect should be the common goal, and retrofit improvements in the residential sector, as small as they may be, can also make a large difference.
Where do I Start?
Now, you may ask, where do I start if I too want to make a difference, lower my costs, and improve my comfort?
Typically, the best way to determine which areas of your property to retrofit is to perform an energy audit or study. An energy audit is an investigation of all things including building footprint, climate zone, airtightness, and insulation properties in walls, ceiling, windows, and doors. Appliances, lighting, and systems for heating and cooling are also evaluated to produce a complete energy performance evaluation of your property under assumed normal operating conditions.
An energy audit also referred to as an energy-assessment, will identify areas or your property that are the least energy-efficient giving you a place to start when thinking of performance upgrades. If you already know where your property could use an improvement, an energy study can be done to identify alternate systems and how much energy would be saved depending on which alternative system is chosen for that specific upgrade.
You can hire an independent company to perform an energy audit or study and some product suppliers even offer them for free. An Energy Audit should be performed by a trained professional so be sure to verify their credentials. We also recommend checking with your local power authority to see if they offer funding towards energy assessments.
Here in British Columbia, Canada, the BC Hydro power authority currently provides funding for businesses to cover between 75-100% of the total cost. Some restrictions apply and, in some cases, if the recommendations made are not implemented, the business may be required to reimburse 25% of the cost back. BC Hydro estimates an energy audit for a business to cost approximately $3000 and up, however it is a small investment specifically if funding is available. Although this program is only available for businesses, there are usually rebates offered to homeowners for energy-efficient upgrades which can help with the cost of your retrofit significantly.
Once energy-efficiency weaknesses have been identified within your property, you can make informed decisions on what retrofit upgrades would benefit you the most and which ones you can afford to implement. Natural Resources Canada (NRCan) separates energy upgrades into 3 retrofit categories: minor, major, and deep.
Different Ways to Energy Retrofit your House
Minor retrofits involve things like resealing air leaks around windows and doors, adding insulation, upgrading lighting and appliances, and installing energy-efficient window coverings. A Major retrofit involves replacing window glazing and doors, updating inefficient heating and cooling systems, installing low-flow faucets with sensors and automatic shut-offs, and installing sub-metering in buildings with multiple occupants to name a few.
A Deep retrofit involves an extensive overhaul of the entire building which may include reconfiguring the interior, replacing the roof, adding or rearranging windows for increased daylight, ventilation, and capturing solar gains. Replacing heating, cooling, and ventilation systems with renewable technology are also included in this category.
Building automation is a key factor not mentioned by NRCan but is acknowledged by many experts as being integral to an energy-efficient environment as mentioned earlier in this article. Automation is so effective because it removes the human factor. For example, when an occupant is cold, they tend to turn up the heat. In an automated environment, the indoor temperature is kept at a constant because the system will raise blinds to capture solar gains instead of resorting to mechanical heating.
Alternately, when solar gains begin to heat the indoor environment beyond the chosen temperature, the system will lower the blinds to prevent overheating and the need for mechanical cooling. Automated systems will also dim or brighten lighting in response to the positioning of blinds to reduce energy demand for lighting when it is not needed. Basically, a “Smart” building is one that responds to changes within the indoor environment and adjusts systems to maintain optimal comfort and reduce the energy demand.
I am not sure where to slot building automation in amongst NRCan’s energy retrofit categories because today, implementing smart technologies is relatively simple and inexpensive. I am inclined to place this in the minor retrofit category however, for large-scale projects this could be considered a major retrofit.
The following are some minor cost-effective retrofit suggestions you as a homeowner can do to improve the energy-efficiency of your property.
Reseal Air leaks: The first thing you should do is check all your windows and doors for air leaks. Making other energy-efficient upgrades without making sure air leaks are blocked, will only result in you being more efficient at heating or cooling the outdoors. Feel for drafts or fluctuations in temperature to find air leaks and block them by re-caulking window seals and installing weather stripping around doorways.
Check Insulation: About 25% of heat in a home is lost through the ceiling and attic and approximately 35% can be lost through walls making insulation a critical component to the building envelope. Check for inefficient insulation by feeling the interior walls when the outdoor temperature is colder than the indoor temperature. If your walls are cold and damp to the touch, then your home requires more insulation. Drafts, ice buildup on roofs, and fluctuating room temperatures are also indications that your home is not sufficiently insulated.
Insulation can be added without tearing down drywall by drilling holes between each wall stud at the top through the exterior siding and spraying insulation into the wall with a hose.
Adding insulation to your home and sealing air leaks are two of the most important energy-upgrades you can do.
Upgrade to Energy-Efficient Window Coverings: Approximately 25% of heat is lost through window glazing for all buildings. This makes efficient window coverings as important as sealing air leaks and properly insulating your property.
There are many effective window coverings available to consumers but it is well known that exterior-mounted solutions are most effective. In Europe, these window coverings have been in use for decades due to the high cost of electricity and the effectiveness of these treatments in lowering energy demand. A paper titled “Solar and daylight management as an essential concept in the energy performance of buildings” published by The European Solar Shading Organization, suggests that solar shading solutions are an essential component for building sustainable buildings. When combined with automation, the energy-saving benefits cannot be denied.
Upgrade Lighting: Lighting accounts for approximately 5% of energy use within your home and as much as 40% in an office building.
According to the US Department of Energy, simply replacing 5 of the most commonly used fixtures in your home with EnergyStar rated lighting, can save as much as $75 per year depending, of course, on the cost of electricity from your utility provider. With the various lighting options available today, choosing an energy-efficient bulb can be difficult. Following are some facts the US Department of Energy published that might make that choice a little easier:
Halogen Incandescents only meet the minimum federal energy efficiency standard (USA).
EnergyStar rated compact fluorescent lamps (CFLs) use approximately 25% of the energy a typical incandescent bulb uses and lasts about 10 times longer. The disadvantage of these bulbs is that they need to be recycled responsibly due to the small amount of mercury they contain. They also take a bit of time to emit their full brightness and most are not useable with a dimmer switch.
Energy Star rated Light-emitting diodes (LEDs) use between 75 and 80% less energy than typical incandescent bulbs and last about 25 times longer (from 40 to 50 years based on 2 hrs. usage per day). LED bulbs do cost more than others but they will save much more in electricity through to their end-life.
Upgrade Heating, Ventilation and Cooling: Since heating and cooling account for about half of energy consumption within your home, this is an important system to evaluate also. Although NRCan places HVAC systems into the “Major” retrofit category, I make another mention of this here because upgrading these systems is where you will see huge benefits in terms of dollars and cents. However, keep in mind that, if implementing dynamic solar shading, mechanical cooling, heating, ventilation, and artificial lighting demands can be greatly reduced or eliminated.
I am by no means an HVAC specialist, so I won’t begin to try and explain the complexity of options available, but I do recommend consulting with an HVAC professional for advice on retrofitting this system if necessary.
There can be much more said about energy retrofits, but hopefully, this article has provided the most important motivators for you to consider undertaking one. As outlined, an energy retrofit can be as simple as replacing light bulbs to as complex as reconfiguring an entire building’s interior. Nonetheless, every measure taken within the building sector will support cooperative efforts around the globe to curb rising CO2 levels in our atmosphere. Even if you are not a strong believer that human activity is the cause of global warming, at least by making energy performance upgrades to your home, you will save money and improve your indoor living environment. The result is a win, win, win for all.