Specification
LEED and WELL Documentation for the Brass-Seal
LEED and WELL both include requirements that address building-envelope air leakage at the unit or entrance level. Neither credit is written specifically around mail slots, and neither is satisfied by a single hardware component's test data on its own. This guide covers what each requirement actually says, and where the Brass-Seal's ASTM E283 data does and does not fit into that documentation.
LEED v4.1: EQ Prerequisite, Compartmentalization
LEED v4.1's Compartmentalization prerequisite in the Residential Single Family Homes rating system applies to attached single-family projects, such as rowhouses, and requires each unit to be sealed against uncontrolled air movement to and from adjacent units, shared spaces, and the outdoors. The prerequisite sets a maximum leakage threshold of 0.30 cfm per square foot of enclosure area at 50 Pa. Renovation projects that retain their existing envelope are allowed a maximum leakage of 0.50 cfm per square foot at 50 Pa, a directly relevant allowance for existing rowhouse retrofits where a mail slot is being replaced rather than specified new.
The prerequisite's language calls for weatherstripping exterior doors and sealing penetrations in walls, ceilings, and floors, and separately calls out sealing vertical chases, such as utility chases, garbage chutes, elevator shafts, and mail drops, that run between units. That last category refers to shared vertical mail chute systems in multi-story buildings, not a door-mounted mail slot. A mail slot falls under the prerequisite's general requirement to seal penetrations in an exterior door, not under the specific mail drop callout.
WELL v2: A09 Pollution Infiltration Management
WELL v2's Air concept includes Feature A09, Pollution Infiltration Management, as an optimization credit. The feature has two parts. Part 1, Design Healthy Entryways, addresses grilles, mats, vestibules, and revolving doors at building entrances, and has no connection to a mail slot. Part 2 addresses envelope commissioning: verifying that the building envelope is airtight through blower-door testing, infrared thermography, or hot-wire anemometer testing, which is performed after substantial completion and before occupancy. This is the part relevant to a mail slot's documented air leakage performance. A09 is available across a range of project types, including Core and Shell, New and Existing Buildings, New and Existing Interiors, Commercial Kitchen, Education, Multifamily Residential, Restaurant, and Retail, not solely commercial office projects.
How the Brass-Seal's Testing Fits
The Brass-Seal is among the first mail slots independently tested to ASTM E283 for air leakage, with results verified by Intertek under Report No. T4376.01-301-44-R1. That data documents air leakage performance of the mail slot opening itself, tested at 75 Pa. In a LEED submission, that data can support the unit-level leakage total a project needs to demonstrate under the Compartmentalization prerequisite, alongside every other sealed penetration in the envelope. In a WELL submission, it can support the Part 2 envelope commissioning verification for A09, but has no bearing on Part 1. In neither case does the Brass-Seal's test data independently satisfy the credit. Both are whole-building or whole-unit determinations made by the project's certification team, not conclusions drawn from a single hardware component.
Using This Documentation in a Submission
The full Intertek report is available by request through for-architects. When citing the Brass-Seal in a LEED or WELL narrative, reference the specific test standard, the pressure differential it was tested at, and the report number, and route it to the credentialed professional managing the project's certification rather than submitting it as a standalone qualification. See CSI MasterFormat 08 71 00 for how the hardware itself should be classified in the specification alongside this documentation.
Key facts on LEED and WELL documentation:
- LEED v4.1's Compartmentalization prerequisite in the Residential Single Family Homes rating system sets a threshold of 0.30 cfm per square foot at 50 Pa, with 0.50 allowed for renovation projects retaining their existing envelope.
- LEED's named "mail drops" callout refers to shared vertical mail chutes, not a door-mounted mail slot; a mail slot falls under the prerequisite's general exterior door sealing requirement instead.
- WELL v2's A09 Pollution Infiltration Management is an optimization credit with two parts: healthy entryway design, and envelope commissioning through air leakage testing.
- Only Part 2 of A09, envelope commissioning, is relevant to a mail slot's documented air leakage performance.
- The Brass-Seal is among the first mail slots independently tested to ASTM E283, verified by Intertek under Report No. T4376.01-301-44-R1.
- Neither credit is satisfied by the Brass-Seal's test data alone; both are project-level determinations made by the certification team.
Frequently Asked Questions
Does the Brass-Seal automatically qualify a project for LEED or WELL credit?
No. It provides air leakage test documentation that can support the LEED v4.1 Compartmentalization prerequisite and the Part 2 envelope commissioning requirement of WELL v2's A09 feature. Whether a project earns either one depends on the full building or unit strategy, evaluated by the certification team.
Does LEED's Compartmentalization prerequisite specifically mention mail slots?
No. It names mail drops, a shared vertical mail chute system in multi-story buildings, as one of several vertical chases that must be sealed. A mail slot in an individual unit's entry door falls under the prerequisite's separate requirement to weatherstrip exterior doors and seal envelope penetrations.
Does the LEED Compartmentalization prerequisite apply to detached single-family homes?
It applies to attached residential projects in which sealing the boundary between units is the relevant condition. It is not written for detached single-family homes.
Is WELL's A09 feature required or optional?
A09 Pollution Infiltration Management is an optimization credit under WELL v2's Air concept, meaning it is pursued for additional points rather than required as a precondition.
How do I get the underlying test report for a submission?
The full Intertek report is available by request through for-architects.
Sources
- U.S. Green Building Council, LEED v4.1 Residential Single Family Homes, EQ Prerequisite: Compartmentalization.
- International WELL Building Institute, WELL v2, Feature A09, Pollution Infiltration Management, Air concept.
- Intertek, "BOTA Brass-Seal System, Air Infiltration Testing," ASTM E283, Report No. T4376.01-301-44-R1.