BOMA 2024: What Changed, From the Team That Helped Write It

ANSI/BOMA Z65.1-2024 is the current measurement standard for office buildings. It has changed what is included as rentable area in four ways that matter to owners: ground-level outdoor amenity space can now be rentable, tenant-exclusive shafts are now a defined space type, a new Non-Allocated Tenant Area (NATA) category keeps single-tenant spaces out of everyone else’s load factor, and Method B got simpler. Each is expanded below.

A building measured under BOMA 2017 or earlier almost certainly calculates differently today, and for many properties the 2024 rentable area is larger.

Stevenson Systems’ team co-authors these BOMA standards, and our founder, Peter Stevenson, is one of only two official BOMA Standard interpreters internationally.

This is our read on what changed and what to do about it.

What Are the Major Changes in BOMA 2024?

1. Ground-Level Outdoor Space Can Now Be Rentable

Under BOMA 2024, ground-level outdoor areas, covered or uncovered, can be included in rentable area when they’re constructed as an amenity for tenant use. Terraces, courtyards, outdoor seating, amenity decks: space that owners have constructed (and tenants have been enjoying) for years can now show up where it belongs, in the rent roll.

For properties with significant outdoor amenity programs, this is the headline change. Area that produced zero rentable feet under 2017 produces real feet under 2024.

Remeasuring under a newer standard routinely surfaces additional rentable area, and standards evolution is one of the main reasons it exists.

2. Tenant Shafts Are Now a Defined, Measurable Space Type

Vertical penetrations that serve a single tenant — think dedicated exhaust, medical gas, or data risers — are now formally defined and classified as rentable to that tenant. Before 2024, these spaces sat in a gray zone that different measurers handled differently.

For ordinary office buildings this is a tidy clarification. For medical office and lab buildings, where tenant-dedicated shafts are everywhere, it’s a meaningful source of rentable area.

3. NATA Keeps One Tenant’s Space Out of Everyone Else’s Rent

The 2024 standard introduces Non-Allocated Tenant Areas: unenclosed tenant areas, tenant storage, and single-tenant shafts that are measured and charged to the tenant who occupies them but excluded from the load factor.

The fairness logic is easy to see. If one tenant has a large private terrace, they should pay for it, and the other tenants on the floor shouldn’t see their load factor inflate because of it. NATA draws that line cleanly.

4. Method B Got Simpler

BOMA’s Method B (the single load factor approach) was rewritten for clarity. It’s now easier to apply correctly and easier to explain to tenants, which matters more than it sounds: allocation methods tenants can’t follow become allocation methods tenants challenge.

Does BOMA 2024 Increase My Building’s Rentable Area?

For many buildings, yes, though the honest answer is: it depends on what you have and when it was last measured.

Buildings most likely to gain under 2024:

• Properties with ground-level outdoor amenities built for tenants: terraces, courtyards, covered seating.
• Medical office and lab buildings with tenant-dedicated shafts and specialized venting.
• Anything last measured under BOMA 2010 or earlier. Two standards of evolution have accumulated since then, and the gap compounds.
• Buildings that were never field-verified at all, where the stated RSF came from drawings rather than measurement.

“The rentable area you found yesterday was measured against yesterday’s standard. The standard evolved. The smart money checks what that’s worth.”

Why Do Standards Changes Create Found Area?

Rentable area is a defined quantity, based on physical measurements. The walls don’t move when BOMA publishes a revision, but the definition of what counts does.

That’s also why finding additional area implies no fault. Owners sometimes hear “your RSF is understated” as an accusation. It isn’t. If the building was measured correctly under the standard of its day, that standard simply isn’t the current one anymore, and the building has had years of tenant changes since.

The opportunity belongs to whoever checks first. On the buy side, knowing a target’s 2024 number before close protects your basis and can surface upside the seller hasn’t priced. On the hold side, found area flows straight into NOI, and every recurring dollar capitalizes into valuation at the prevailing cap rate.

What Should Owners Do Now?

Inventory your portfolio by measurement vintage. Which standard, what year, was it field-verified, by whom. For many portfolios this exercise alone is revealing: the answers range from “BOMA 2017, verified” to a shrug.

Prioritize the assets where 2024 bites hardest. Outdoor amenities, MOB and lab product, anything pre-2010, anything unverified. That’s your remeasurement shortlist, ranked by likely found area.

Get a definitive read, not a second opinion. Measurement firms can disagree on edge cases; that’s what interpretation questions are. Stevenson Systems’ position as standards co-authors and official interpreters means our read of BOMA 2024 is the definitive one. Our numbers are built to hold up with tenants, lenders, and buyers.

Keep it current once it’s current. A 2024 remeasurement starts aging the day it’s delivered, as tenants change and walls move. Pairing measurement with ongoing updates, like our TruSpace platform, keeps the number live instead of letting it slip out of date again.

Frequently Asked Questions

What is BOMA 2024?

ANSI/BOMA Z65.1-2024 is the current standard method of measurement for office buildings, published by BOMA International. It supersedes the 2017 standard.

What changed between BOMA 2017 and BOMA 2024?

The headline changes: ground-level outdoor amenity areas can now be included as rentable, tenant-exclusive shafts are a defined rentable space type, a new NATA category excludes single-tenant areas from shared load factors, and Method B was simplified.

Do I have to remeasure my building under BOMA 2024?

BOMA standards do not always require a remeasurement. However, owners who do remeasure under the current standard frequently capture rentable area the older measurement couldn’t.

How much rentable area does a remeasurement typically find?

On average, Stevenson Systems clients find 3 to 4% additional rentable area in Class A office properties, based on comparable engagements. Figures are averages, not guarantees; every building is different.