Prerequisites/Mandatory Measures- 7
Minimum Points – 6
Maximum Points – 21

This category aims to improve the air quality inside the home. Indoor air can be as much as 10-times more polluted than outside air, even in industrialized cities. According to the EPA, pollutant levels from individual sources inside the home (such as adhesives, composite furniture, chemicals in carpeting, paint, sealants, cleaning products, combustion etc.) may not pose a significant health risk by themselves, but most homes have more than one source that contributes to indoor air pollution. There can be a serious health risk from the cumulative effects of these sources. See our Article on Indoor Air Quality for a thorough analysis of the sources and effects of indoor air pollution, and how to eliminate risks.

This Category is divided into 10 sub-categories, most containing prerequisites, and consequently the summary below will discuss together the prerequisites and possible additional points that may be earned in each sub-category.

Energy Star® with Indoor Air Package (maximum 13 points). There are no prerequisites. If the home completes the requirements in the Energy Star® with Indoor Air Package then it will receive 13 points. The Package is an extremely detailed set of building guidelines that involve the entire building process – in essence, it is a complete set of building guidelines juxtaposed onto the LEED® for Homes guidelines, and the USGBC, in creating the LEED of Homes guidelines, did not isolate specific components of the Energy Star® with Indoor Air Package that deal with indoor air quality. Perhaps the reason that the entire building package is incorporated by reference into the LEED® for Homes indoor air quality guidelines is because many aspects of construction (such as building envelope decisions regarding windows, ventilation, type or insulation, water and moisture control measures, radon elimination, pest barriers) collaterally impact on indoor air quality in addition to those aspects that obviously primarily deal with air quality such as ventilation and ductwork, combustion sources, carbon monoxide safety and low-VOC materials. Because the Package is a complete set of building guidelines, meeting the requirements will coincidentally lead to points in other categories including the durability issues in the Innovation and Design Process; Sustainable Sites non-toxic pest control; Energy and Atmopsphere HVAC design and installation; and Materials and Resources use of environmentally preferable materials.

Combustion Venting (maximum 2 points) strives to minimize the leakage of combustion gases into the occupied space. Prerequisites include ensuring that a) no unvented combustion appliances (i.e. decorative logs) are installed, b) carbon monoxide monitors are installed on each floor, c) all fireplaces and wood stoves have doors, and d) space and water heating equipment that use combustion must either be designed and installed with closed combustion (sealed air supply and exhaust ducting), or with power-vented exhaust, or be located in a detached utility shed or in the open air. Up to 2 points may be earned if fireplaces and woodstoves are eliminated entirely or are installed in conformity with criteria set out in the Guidelines.

Moisture Control (maximum 1 point) aims to reduce indoor moisture levels for comfort, decreased mold risk and increased durability. There are no prerequisites. A point may be earned if the home is in a locale where humidity is an issue and dehumidification equipment is installed.

Outdoor Air Ventilation (maximum 3 points) strives to reduce exposure to indoor pollutants by ventilating with outdoor air. There is a delicate balance between over- and under-ventilating – from a health perspective it is important not to under-ventilate, but from an energy perspective it is important not to over-ventilate. Keep in mind that some inevitable leakage from the building envelope contributes to the overall ventilation of the building.

The prerequisites involve ensuring a minimum acceptable level of outdoor air ventilation according to ASHRAE (American Society of Heating, Refrigerating and Air Conditioning Engineers) Standards for the geographic location of the home. 2 points can be earned for exceeding these standards by employing such measures as a whole-house ventilation system, or in cold climates a heat-recovery ventilation (HRV) system or an energy-recovery ventilator (ERV) that provides heat transfer between the incoming outdoor air and the exhaust air stream, both of which work on the principle that heat or energy can be reclaimed from exhaust airflows. HRVs use heat exchangers to heat or cool incoming fresh air, recapturing 60 to 80 percent of the conditioned temperatures that would otherwise be lost and making your heating system work less hard to heat the warmer incoming air. Energy Recovery Ventilators (ERVs) exchange moisture between the two air streams, typically from the incoming humid air in the summer to the exhaust stream but they cannot be relied upon for total dehumidification needs. In addition, one point may be earned for third party testing and verification.

Local Exhaust (maximum 2 points) aims to reduce moisture and indoor pollutants in bathrooms and kitchens. The prerequisites require that all bathrooms and kitchens be ventilated according to ASHRAE standards, that the fans and ducts be installed according to ASHRAE standards and be vented to the outdoors, and that Energy Star® labeled bathroom exhaust fans be used (except for exhaust fans the serve multiple bathrooms). In the kitchen the minimum air flow rate is 100 cfm (cubic feet per minute) and a vented hood is required if the exhaust fan flow rate is less than 5 kitchen air changes per hour. Bathroom minimum air flow rate is 50 cfm.

One point can be earned if every bathroom has an occupancy sensor, or an automatic humidistat controller, or an automatic timer to operate fans for a timed interval after the occupant leaves, or a continuously operating exhaust fan. An additional point can be earned for third party testing and verification.

Distribution of Space Heating and Cooling (maximum 3 points) strives to achieve uniformity of heating and cooling throughout the house.

Forced Air Systems: Prerequisites require room by room load calculations, using ACCA and ASHRAE methods, to determine the proper amount and location of ductwork. One point can be earned by providing for adequate return air flow in every room by meeting specified duct size requirements or prescribed air pressure differentials between closed rooms and adjacent spaces. Two points can be earned by third party testing.

Non-ducted HVA Systems, such as hydronic (hot water) systems: Prerequisites require that engineering design calculations, using ACCA and ASHRAE methods, be done for each room.  One point can be earned by including flow controls on each radiator, and 2 points can be added for designing the system with at least two distinct, thermostatically controlled zones.

Air Filtering (maximum 2 points) strives to reduce the amount of particulate matter in the air. For both Forced Air Systems and Non-ducted HVA Systems, such as hydronic (hot water) systems, the prerequisites include installing air filters with a Minimum Efficiency Reporting Value (MERV) at or above 8 and ensuring that air handlers can maintain adequate pressure and are airtight. MERV refers to the rating measurement scale developed by ASHRAE to determine how effective a filter is at removing particles of a certain size -- the higher the rating the better the filter is at removing particles. A rating of 8 or above means that the filter will remove 20-35% of particles that are 3 to 10 microns in size (mold spores, for example vary from 4 to 40 microns, most being less than 10). By comparison, MERV 14 filters are typically the filter of choice for critical areas of hospitals (to prevent transfer of bacteria and infectious diseases). Up to 2 points can be earned for specifying filters with higher ratings.

Contaminant Control (maximum 4 points) strives to reduce the occupants’ and construction workers’ exposure to indoor airborne contaminants by controlling them at their source and by careful removal. There are no prerequisites. One point can be earned for sealing all ductwork during the construction. Up to 2 points can be earned by either furnishing floor mats at each entry, or incorporating a shoe removal storage space near the primary entryway, or installing a central vacuum system with an outdoor exhaust. One point may be earned by flushing the home with fresh air after construction is complete, before occupancy, for at least 48 (need not be consecutive) hours and replacing HVAC filters afterwards.

Radon Protection (maximum1 point) aims to reduce exposure to radon gas and other soil gas contaminants. The prerequisite requires that if the home is in an EPA Radon Zone then EPA radon-resistant construction techniques must be followed, but in a renovation scenario where the foundation and earth is not being disturbed, this may be of little relevance. New York City is in Zone 3, lowest potential. One point can be earned if the house is not within Radon Zone 1 but radon-resistant techniques are still employed.

Garage Pollutant Protection (maximum 3 points) aims to reduce exposure to garage fumes. The prerequisite requires that no HVAC equipment be located in the garage. Two points can be earned by tightly sealing all shared surfaces between the garage and the occupied spaces (such as seal all joins and cracks, floor and ceiling joists, paint walls and ceilings, weather strip doors, install CO detectors). An additional point can be earned by installing an exhaust fan it the garage that runs continuously, or runs off an automatic timer linked to an occupant sensor or garage door mechanism or light switch.

What does this mean for brownstone and row-house renovation: The Energy Star® with Indoor Air Package is, in itself, a complete set of building guidelines juxtaposed on top of LEED®, and as developed by Energy Star were aimed toward the new-build market, not renovations; incorporating them seems to complicate matters in the context of a renovation.  Familiarizing yourself with them, however, is a great educational excercise (as is familiarizing yourself with the LEED® for Homes guidelines) because it will make you aware of a lot of potential areas where you can incorporate green attributes into your project. Understanding the sources of indoor air pollution and how to reduce or eliminate them may be a more workable approach, and see our Article Indoor Air Quality -- Identifying Sources and Making Renovation Choices that Eliminate Contamination for guidance in this regard. The guidelines dealing with combustion venting, outdoor venting, moisture control and contaminant control are workable, often common sense, criteria and provide a good road map for dealing with the issues. Radon is a low risk in New York according to the EPA.