T01: Thermal Performance – Above Green

(Required)

INTENT

Ensure that the majority of building users find the thermal environment acceptable.

SUMMARY

This WELL feature requires projects to create indoor thermal environments that provide comfortable thermal conditions to the majority of people in support of their health, well-being and productivity.

ISSUE

The indoor thermal environment is ranked as one of the strongest contributing factors to overall human satisfaction in the built environment. The thermal environment impacts human health, comfort and productivity. Due to its linkages to integumentary, endocrine and respiratory body systems, thermal comfort can cause a variety of detrimental health outcomes. For example, cold and dry spaces are known to facilitate the spread of the influenza virus because low humidity levels allow the virus to persist longer in the air, while low air temperature extends the virus shedding period. On the other hand, overly warm indoor spaces are linked to increases in sick building syndrome symptoms, irregular heart rate, respiratory issues, fatigue and negative mood. Warm and humid indoor spaces are also associated with mold and fungal growth.

SOLUTIONS

Thermal comfort standards utilize a model that provides a means of predicting whether humans in a mechanically conditioned space will be satisfied with the thermal environment based on six core parameters: air temperature, humidity, air movement, mean radiant temperature of surrounding surfaces, metabolic rate and clothing insulation. For naturally conditioned buildings, the adaptive thermal comfort model correlates human comfort directly with indoor operative temperature and outdoor temperature. Achieving thermal satisfaction among people requires some level of control over thermal comfort parameters in any given environment.

IMPACT

Controlling the thermal environment substantially impacts a building's energy footprint, as in many countries heating and cooling account for approximately half of a building’s energy consumption. Furthermore, thermal conditions play a large role in the way we experience the indoor environment.

REQUIREMENTS

Part 1

Support Thermal Environment

Verified by MEP, Performance Test, Professional Narrative

For All Spaces except Commercial Kitchen Spaces & Dwelling Units

Choose between the following:

Option 1. Mechanically ventilated spaces:

The following requirements are met:

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.
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%.
Projects submit assumptions of clothing insulation and metabolic rate (and for projects using the elevated air speed method, air speed at a height between 0.6 and 1.7 m [2 to 5.6 ft]) used in design calculations.

Option 2. Naturally ventilated spaces:

One of the following requirements is met:

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

Note: Mixed-mode-conditioned spaces are deemed compliant with the feature if requirements for both mechanically and naturally conditioned spaces are satisfied.

For Commercial Kitchen Spaces

The following requirement is met:

The operative temperature in the kitchen does not exceed 27 °C [80 °F] at any time.

Note: Mixed-mode-conditioned spaces are deemed compliant with the feature if requirements for both mechanically and naturally conditioned spaces are satisfied.

For Dwelling Units

All regularly occupied spaces meet one of the following requirements:

Satisfy the conditions listed for “All spaces.”
Meet the below:
1. If the local climate requires cooling, each dwelling unit has the flexibility to accommodate the installation of cooling device(s) that allow tenants to maintain desirable comfort conditions in bedrooms and living spaces.
2. Project owner identifies at least three types of cooling mechanisms (e.g., split systems, ceiling fans or other systems that improve thermal comfort) and provides installation assistance for the cooling mechanism selected by a tenant.
3. Project owner educates or assists tenants with maintaining their cooling mechanism(s).
4. Projects provide a heating system to meet minimum temperature requirements from ASHRAE 55:2013, ISO 7730:2005 or EN 15251:2007.

Note: Mixed-mode-conditioned spaces are deemed compliant with the feature if requirements for both mechanically and naturally conditioned spaces are satisfied.

Part 2

Monitor Thermal Parameters

Verified by Owner, On-going Data Report

For All Spaces

Conduct ongoing monitoring according to the following requirements:

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.
The number and location of sampling points comply with the requirements outlined in the Performance Verification Guidebook.

Note: For on-going monitoring, projects are not required to use devices or methods that comply with the requirements described in the Performance Verification Guidebook. However, if measurements are undertaken by a WELL Performance Testing Agent in compliance with the Performance Verification Guidebook, results submitted to GBCI from each year and test location may be averaged and utilized for recertification purposes.