The ANSI/ASHRAE/IES Standard 100-2015 Energy Efficiency in Existing Buildings provides comprehensive procedures to improve the energy efficiency of buildings. Although Standard 100 provides direction for residential and non-residential buildings, the purpose of this article is to describe the application of Standard 100 to residential buildings.
The Energy-Use Intensity (EUI) of a building is calculated as the annual net energy use divided by the gross floor area (expressed either as MJ/m2 or BTU/ft2). When calculating the EUI, building energy-use data for twelve consecutive months within the last 18 months must be considered. The energy targets for a building depends on the climate zone in which the building is located. Table 1 shows the climate zone number for major cities in Canada together with the Energy Targets for single-family detached residential buildings. Buildings that meet their energy targets are not required to perform an energy audit.
Table 1 - Energy Target for Single-Family Detached Homes in Major Canadian Cities
Performing an Energy Audit
In accordance with Standard 100, buildings that do not meet their energy targets are required to undergo an energy audit. As part of the audit, the historical energy use is allocated to end uses such as HVAC, lighting, domestic hot water, and electrical plug loads. Once the energy audit has been completed, the energy efficiency measures (EEMs) to be implemented are selected and the estimated energy savings for the EEMs is calculated. An adjusted EUI is calculated that considers what the EUI would be with the EEMs implemented. Once the adjusted EUI meets the energy target, then the EEMs are implemented.
The energy savings is expressed in both cost units as well as energy units. The cost of implementing each EEM is included together with the simple payback for each EEM or the recommended package of EEMs. Once the EEMs have been implemented, the building's EUI is monitored until twelve consecutive months of data demonstrate that the energy target has been achieved.
For more information about this topic, please contact us.
The June 2017 issue of the ASHRAE Journal features an article on measurement of indoor airborne particulate matter. The article cautions against comparing real-time nephelometric measurements of particulate matter to USEPA National Ambient Air Quality Standards for particulate matter or OSHA standards.
Nephelometers detect particles and measure light scattering by the particle. A mass concentration estimate can be obtained based on assumptions about optical properties and density. Real-time multi-fraction particle counters can be useful in refining building assessments beyond the use of CO2 concentrations as an indicator of ventilation. Although there are no health-based guidelines for PM limits using real-time count concentration values, comparing indoor results to outdoor results or assessing spaces over time can provide "practical, inexpensive guidance on managing the PM burden in a space" (p. 86). Fine particles have been associated with cardiovascular disease while coarse particles have been associated with respiratory disease, although there is an overlap in effects.
The CBC news featured an article today titled "Diesel pollution vastly underestimated, contributes to global deaths". The article discusses a research study published in Nature that suggests that air pollution from diesel vehicles is more than 50 percent higher than shown in government lab tests. The researchers estimated that the additional pollution equates to an additional 38,000 deaths from soot and smog in 2015.
Over the last two weeks, there have been several news stories related to high concentrations of carbon monoxide in indoor air leading to death. On March 23, 2017, Global News published an article, "16 Mandarin restaurant employees in Scarborough hospitalized with carbon monoxide symptoms". On April 1, 2017, CTV featured an article, "Hotel carbon monoxide leak kills child, sickens others in Michigan", about a carbon monoxide leak at a hotel that killed one child and made approximately twelve other people ill. On April 3, 2017, CBC News published an article, "A life off the grid: Idyllic then deadly" about four people killed from carbon monoxide poisoning in British Columbia as a result of carbon monoxide leaking from a propane-powered hot water tank. On April 2, 2017, the Globe and Mail featured an article, "Most Canadians unprotected against carbon monoxide, fire chiefs say".
Carbon monoxide is an odourless, colourless, tasteless gas that is a byproduct of fuel combustion, irrespective of the type of fuel used. Appliances or motor vehicles that produce carbon monoxide become a risk when there is poor ventilation, and the carbon monoxide accumulates to dangerous levels. At low concentrations of carbon monoxide, adverse health effects may be experienced including tiredness, headaches, muscle weakness or shortness of breath. At high concentrations or when exposed to low concentrations of carbon monoxide over time, symptoms may include dizziness, chest pain or difficulty thinking.
Carbon monoxide combines with the oxygen-carrying sites on hemoglobin in the blood, with an affinity 210 to 240 times higher than that of oxygen. The resulting carboxyhemoglobin is unable to carry oxygen. Occupational health and safety codes recommended a maximum 8-hour exposure limit of 25 ppm.
In order to reduce the risk of exposure to high levels of carbon monoxide in indoor air, the following actions are recommended:
An article in Popular Science by Sara Chodosh and Kendra Pierre-Louis titled "Here's how air pollution kills 3,450,000 people a year" discusses a recently released study on air pollution and premature death. The study, published in Nature, shows that approximately 12% of premature deaths were caused by air pollution released elsewhere in the world. Particulate matter that is 2.5 microns and smaller (PM2.5) is especially problematic because of its ability to transfer from the lungs to the cardiovascular system. The article also indicates that the Clean Power Plan, which President Trump just rescinded, would not only have had significant benefits in terms of greenhouse gas reductions, but it also would have significantly reduced PM2.5, saving lives.
The Globe and Mail featured an article on March 24, 2017 titled "Asbestos found in U of T labs stokes concern from faculty, students". The article indicates that dust containing asbestos has been found in multiple labs at the University of Toronto's medical-sciences building. A major renovation has been undertaken of the building, which is almost 50 years old. Although any asbestos use will be banned in Canada by 2018, the University of Toronto incident illustrates the challenges associated with addressing the legacy of asbestos containing materials.
The March 29, 2017 issue of the Calgary Herald features an article by Shawn Logan titled "Study finds deadly radon gas exceeds safe levels in one of eight Calgary homes". A study by University of Calgary researchers published in CMAJ Open Journal found that 12.4% of the 2382 homes tested in Calgary had radon levels higher than acceptable levels. Radon is the second leading cause of lung cancer in Canada and claims 3200 Canadian lives each year.
The March 2017 issue of the ASHRAE Journal features an article, titled Formaldehyde Emissions from Laminate Flooring by Francis J. Offermann. The article describes an error that the Centers for Disease Control and Prevention (CDC) made in its report on potential exposures to and health risks of formaldehyde in laminate flooring from Lumber Liquidators manufactured in China prior to 2016. The urea-formaldehyde resins used in the medium density fibreboard (MDF) of the laminate flooring in question releases free formaldehyde following installation, but formaldehyde is also released as a result of hydrolysis caused by indoor relative humidity, and this latter source of emissions was not considered in the CDC report. According to the author's own modelling, the calculated cancer risks using the corrected formaldehyde emissions decay rate for laminate flooring is more than 12 times higher than the risks reported by the CDC.
Exposure to Lumber Liquidators laminate flooring represents both cancer and non-cancer health risks. Neither air scrubbers nor ventilation are an effective means of reducing these risks; only removal of the flooring can completely mitigate the risks. The author states that alternate resin systems such as phenol-formaldehyde resin are much more stable than urea-formaldehyde resin, and do not release formaldehyde when exposed to humidity.
This week, the World Health Organization (WHO) released two reports on children's health and the environment. The reports describe threats to children's health such as toxins from improperly recycled electrical and electronic waste. The report also notes that the rise in temperatures and carbon dioxide associated with climate change increases pollen growth, which is associated with increased asthma rates. The report indicates that 44% of asthma symptoms reported in children are related to environmental exposures. The reports can be found here on the WHO website.
New research from Washington University's School of Medicine in St. Louis suggests that welders exposed to airborne manganese at concentrations lower than current occupational health and safety standards exhibit neurological problems similar to Parkinson's disease. The results were published on December 28, 2016 in Neurology ("Dose-dependent progression of parkinsonism in manganese-exposed welders") and suggest that current occupational health and safety standards for welding fumes may be inadequate to protect welders.