What Are BOMA Area Calculations & Why Do They Matter for Commercial Buildings?

Accuracy in commercial real estate is not optional it’s essential. Whether you are a property owner, landlord, asset manager, or facility manager, the way a building is measured directly impacts revenue, occupancy cost, leasing decisions, and long-term financial performance. In the commercial property world, one standard has become the benchmark for building measurement: BOMA area calculations. 

For decades, BOMA (Building Owners and Managers Association) has provided globally recognized standards for measuring building areas. Their guidelines ensure that all parties speak the same language when determining usable space, rentable space, common areas, and load factors. Without these standards, misunderstandings between landlords and tenants would be far more frequent, lease negotiations would be less transparent, and buildings could lose value due to inaccurate or inconsistent measurements. 

This article explores what BOMA area calculations are, how they work, why they matter, and the significant financial influence they have on commercial buildings. By the end, you’ll understand exactly why BOMA compliance is critical for building owners and property professionals. 

BOMA is the leading authority that establishes how commercial buildings should be measured. Their standards apply to office buildings, industrial facilities, retail properties, and mixed-use spaces. The reason BOMA has become the industry standard is simple: it creates fairness, transparency, and consistency. 

Before standardized measurement methods existed, buildings were often measured inconsistently — sometimes exaggerated, sometimes understated, sometimes interpreted differently by different stakeholders. This left landlords and tenants exposed to disputes and inaccurate cost assessments. 

BOMA created clearly defined guidelines so that everyone measures the same way using the same rules. These rules outline how to calculate usable areas, rentable areas, common-area load factors, and circulation spaces. As buildings evolve, tenants change, and shared spaces expand, BOMA standards continue to adapt to real-world building conditions. 

BOMA area calculations refer to the standardized methods used to measure the square footage of commercial buildings. The calculations define how to determine: 

• Usable Area (UA) – the actual space a tenant can use 
• Rentable Area (RA) – usable area plus a share of common areas 
• Load Factor (LF) – the ratio used to convert usable area into rentable area 

These calculations ensure that measurements follow consistent rules, which helps building owners market their space correctly and helps tenants understand exactly what they are paying for. 

One of the biggest sources of confusion in commercial leasing is the distinction between usable area and rentable area. BOMA helps remove that confusion by clearly defining each term. 

Usable area refers to the actual working space a tenant occupies — the private area behind their suite doors. This includes offices, meeting rooms, open workspaces, and storage areas that belong exclusively to that tenant. 

Usable area does not include lobbies, corridors, shared restrooms, elevator banks, or building amenities. 

Rentable area includes usable area plus a proportionate share of building common areas. These areas include hallways, lobbies, shared restrooms, mechanical rooms, and sometimes amenities like fitness centers or conference rooms. 

Rentable area is larger than usable area because tenants contribute to the cost of shared spaces. 

Load factor is calculated using the ratio between total common areas and the usable area of the building. BOMA provides strict guidelines on how these elements are measured and assigned. 

Accurate measurements are the foundation of commercial property operations. The financial stakes are high, and Boma Floor Plans ensures BOMA calculations protect both owners and tenants in multiple ways. 

For landlords, rentable area determines rental income. If the calculations are incorrect, revenue projections suffer. Overstated areas can lead to legal issues, while understated areas result in lost revenue. BOMA area calculations ensure that every square foot is measured fairly and clearly. 

Tenants want to know exactly what they are paying for. BOMA standards eliminate ambiguity and provide a universal method for determining rentable square footage. This transparency helps avoid disputes and builds stronger tenant trust. 

Appraisers and investors rely heavily on area measurements. Inaccurate calculations can lead to undervaluation or overvaluation of an asset. BOMA-compliant measurements protect the integrity of valuations and help investors make confident decisions. 

When architects and space planners work with inaccurate measurements, the result can be costly redesigns, wasted construction budgets, and inefficient layouts. BOMA ensures that planning is accurate from the start. 

In many markets, BOMA standards are no longer optional—they are expected. Tenants, leasing brokers, and consultants rely on them to compare properties. A building measured differently will immediately raise red flags. 

For companies managing multiple properties, using a standardized system like BOMA ensures that all buildings are measured uniformly. This simplifies reporting, budgeting, and portfolio-wide performance analysis. 

A professional BOMA calculation involves a detailed measurement methodology. Specialists use floor plans, on-site measurements, and digital tools such as CAD and BIM modeling to determine precise areas according to BOMA standards. 

The process includes: 

1. Reviewing architectural plans and building documentation 
2. Measuring usable areas suite by suite 
3. Identifying shared spaces for core factor calculations 
4. Applying BOMA measurement formulas 
5. Verifying calculations through cross-checking 
6. Preparing official BOMA area reports and load factors 

This meticulous process ensures accuracy and compliance. 

Buildings evolve over time. Remodels, layout changes, core expansions, and tenant improvements can all change a building’s measurements. 

Regular re-measurements are essential for: 

• maintaining accurate rentable areas 
• adjusting lease agreements 
• updating valuations 
• ensuring fair cost allocation 

Many buildings owners schedule BOMA recalculations every 3–5 years to maintain accuracy. 

BOMA area calculations play a critical role in maintaining fairness, accuracy, and transparency across the commercial real estate industry. By providing a clear and standardised method for measuring usable and rentable areas, BOMA helps landlords protect revenue, tenants understand exactly what they’re paying for, and investors make confident decisions based on reliable data. For precise, compliant, and professionally verified measurements, contact us today to schedule your BOMA area calculation and ensure your building is accurately represented. 

As buildings evolve and market expectations grow more sophisticated, adhering to BOMA standards is no longer optional — it’s a fundamental part of managing and valuing commercial property. 

1. What are BOMA area calculations? 

They are standardized measurement methods defined by the Building Owners and Managers Association to determine usable area, rentable area, and load factors for commercial properties. 

2. Why are BOMA calculations important? 

They ensure financial accuracy, leasing transparency, compliance, and consistent valuation across commercial buildings. 

3. What is the difference between usable area and rentable area?

Usable area is the space a tenant occupies exclusively. Rentable area includes usable area plus a share of common areas such as lobbies and hallways. 

4. Does BOMA 2017 increase rentable area? 

In many cases, yes. BOMA 2017 recognizes more shared and outdoor spaces, which can increase rentable area fairly and accurately. 

5. Who needs BOMA area calculations? 

Landlords, property managers, facility managers, investors, architects, and tenants all rely on BOMA-compliant measurements.