Appendix: Thermal Comfort

 

T01.1 — Support Thermal Environment
Choose between the following:

Mechanically ventilated spaces:
The following requirements are met:

1. During 98% of the standard occupied hours of the year, 95% of regularly occupied spaces achieve thermal conditions representing Predicted Mean Vote (PMV) levels within +/- 0.5; PPD ≤ 10% (as per ASHRAE 55-2013, ISO 7730: 2005 or EN 15251:2007). Project describes outdoor weather conditions under which PMV and PPD levels would not be achieved, including historical weather data demonstrating that they are not expected to occur more than 2% of standard occupied hours per year.
2. During all standard occupied hours of the year, all regularly occupied spaces achieve thermal conditions representing Predicted Mean Vote (PMV) levels within +/- 0.7; PPD ≤ 15%.
3. Projects submit assumptions of clothing insulation and metabolic rate (and for projects using the elevated air speed method, air speed at a height between 2 to 5.6 ft) used in design calculations.

Naturally ventilated spaces:
One of the following requirements is met:

 

1. 80% acceptability limit (as per ASHRAE 55-2013) in regularly occupied spaces.
2. Class I or II acceptability limit (as per EN 15251:2007) in regularly occupied spaces.

 

T01.2 — Monitor Thermal Parameters
Conduct ongoing monitoring according to the following requirements:

1. The dry-bulb temperature, relative humidity, air speed (only for projects that use elevated air speed method) and mean radiant temperature are monitored in regularly occupied spaces within the building at intervals no less than twice a year (once in winter and once in summer season), and results are annually submitted through WELL Online.
2. The number and location of sampling points comply with the requirements outlined in the Performance Verification Guidebook.

 

T02.1 — Enhance Thermal Environment
Choose between the following:

Mechanically ventilated spaces:
The following requirement is met:

1. During all standard occupied hours of the year, all regularly occupied spaces achieve thermal conditions representing Predicted Mean Vote (PMV) levels within +/- 0.5; PPD ≤ 10% (as per ASHRAE 55-2013, ISO 7730:2005 or EN 15251:2007).

Naturally ventilated spaces:
During all standard occupied hours of the year, all regularly occupied spaces achieve one of the following thermal conditions:

 

1. 90% acceptability limit (as per ASHRAE 55-2013).
2. Class I acceptability limit (as per EN 15251:2007).

 

T02.2 — Achieve Thermal Comfort
For All Spaces except Commercial Kitchen Spaces & Dwelling Units
A post-occupancy survey is administered at least twice a year, including once in June, July or August and once in December, January or February, at least six months after occupancy, which satisfies the following conditions:

1. All regular building occupants are invited to participate in the anonymous survey.
2. Responses are collected from the following number of respondents
   1. At least 35% the total occupants if more than 45 occupants are solicited.
   2. At least 15 occupants if solicited occupants number is between 20 and 45.
   3. At least 80% of the total occupants if fewer than 20 occupants are solicited.
3. The survey includes an assessment of overall satisfaction with thermal performance and identification of thermal comfort-related issues in accordance with either:
   1. The sample survey in Appendix T1.
   2. Any pre-approved survey listed in Part 1: Administer Project Survey in Feature C03: Occupant Survey.
4. The results of the survey responses comply with one of the target satisfaction thresholds as specified in the table below:

 

Thermal Comfort Satisfaction Thresholds	Points
80% of regular occupants	1
90% of regular occupants	2

 

T03.1 — Ensure Thermostat Control
The following requirements are met for all regularly occupied spaces equipped with a heating and/or cooling system:

1. All regularly occupied spaces contain thermal zones, as shown in the table below (note: individual rooms less than 320 ft2 or 5 occupants are still considered separate zones):
2. Temperature sensors are positioned at least 3.3 ft away from direct sunlight, air supply diffusers, mechanical fans and heaters and away from exterior walls, windows and doors or any other significant source of heat or cold.
3. All regular building occupants have control over temperature through either:
   1. Thermostats present within the thermal zone.
   2. Digital interface available on a computer or phone.

 

T03.2 — Promote Free Address
For Office Spaces:
Projects meet the following requirements:

1. The building provides a thermal variation of at least 5 °F across open workspaces over 2,150 ft², between rooms with more than 10 people and/or between floors.
2. All office spaces with employees performing tasks that require similar workstations use free address to allow employees to select a work space with a desired temperature.

 

T04.1 — Ensure Personal Thermal Comfort
Points are awarded based on the proportion of regular building occupants that are covered by at least one of the following requirements:

 

Sit-Stand Desks	Points
50 – 99%	2
100%	3

 

1. In all regularly occupied and shared spaces within the same heating or cooling zone, regular building occupants have access upon request to personal thermal comfort devices (e.g., personalized fans, heated/cooled chairs, and others, except combustion-based space heaters) that provide individual user control of air speed, air temperature and/or mean radiant temperature.
2. b. All rooms with a heating and/or cooling system that are regularly occupied by a single occupant meet one of the below conditions:
   1. Occupant has the ability to adjust the temperature.
   2. Occupant has access to personal thermal comfort devices.
   3. Implement localized air delivery as described in Part 4: Implement Advanced Air Distribution of Feature A06: Enhanced Ventilation.

 

T04.2 — Facilitate Thermal Adaptation
Projects meet the following requirements:

1. All occupants have access upon request to blankets. Used shared blankets are washed at minimum on a weekly basis.
2. A flexible dress code policy allows for individual thermal preferences.

 

T05.1 — Implement Radiant Systems
At least 50% of the floor area of regularly occupied spaces within the project boundary is serviced by one of the following systems:

1. Hydronic radiant heating and/or cooling systems.
2. Electric radiant systems.

 

T05.2 — Implement Dedicated Outdoor Air Systems
Mechanically ventilated spaces:
In spaces where an independent system is used for heating and/or cooling, dedicated outdoor air systems meet one of the following requirements:

1. The system complies with ASHRAE Design Guide for Dedicated Outdoor Air Systems (2017).
2. A detailed design review of the proposed system is conducted by an independent, qualified and registered professional mechanical engineer demonstrated not to have a conflict of interest. The review addresses thermal comfort (dry-bulb temperature, humidity and air velocity, at a minimum) and ventilation rates, as well as overall serviceability and system reliability. Reports must demonstrate satisfactory compliance with ventilation standards of Part 1: Ensure Adequate Ventilation in Feature A03: Ventilation Effectiveness.

 

T06.1 — Monitor Thermal Environment
Thermal comfort monitors:
Projects monitor dry-bulb temperature, relative humidity, air speed and mean radiant temperature in regularly occupied areas within the building, satisfying the following requirements:

1. Measurements are taken in occupied zones at least 3.3 ft away from exterior walls, doors, direct sunlight, air supply/exhausts, mechanical fans, heaters or any other significant source of heat or cold.
2. The sensor placement density is minimum one per floor or one every 3,500 ft2, whichever is more stringent.
3. Measurements are taken at intervals and heights specified in the table below:


4. Data are analyzed for regularly occupied hours (e.g., median, mean, 75th and 95th percentile) and annually submitted through WELL Online.
5. Dry-bulb temperature and relative humidity sensors are recalibrated or replaced annually and certificates attesting their calibration or replacement are annually submitted through WELL Online. Air speed and mean radiant temperature sensors used for quarterly measurements are calibrated as per manufacturer's specification.

Environmental measurse display:
Real-time display of dry-bulb temperature and relative humidity is made available to occupants through one of the following:

 

1. At least one monitor screen prominently positioned at the height of 3.6–5.6 ft per 10,000 ft² of regularly occupied space.
2. b. A website or phone application. At least one visible sign is positioned per 10,000 ft² of regularly occupied space indicating the website or phone application where the data may be accessed.

 

T07.1 — Manage Relative Humidity
All parts of the project except high-humidity areas meet one of the following requirements:

1. The mechanical system has the capability of maintaining relative humidity between 30% and 60% at all times by adding or removing moisture from the air.
2. The modeled relative humidity levels in the space are between 30% and 60% for at least 98% of all business hours of the year.

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