5 Ways to Reduce Office Carbon Footprint by Understanding Occupancy

Carbon footprint reduction has left the planning phase and entered the implementation phase. COP30, which wrapped up in Belem, Brazil, last November, made that transition explicit. It was branded the COP of implementation, the end of negotiating targets and the start of executing on them. 

Corporate real estate carries a sizable contribution to an organization’s carbon footprint. McKinsey attributes 39% of global carbon emissions to real estate, split between 11% from building materials and 28% from how buildings are actually run day to day. That second number, operations, is the one workplace, facilities and CRE teams can move without a single construction project. 

Across office portfolios, that 28% scales depending on occupancy. A floor lit, heated, air conditioned and serviced for 200 people produces close to the same emissions whether 190 of them show up or 40 do. If you want to cut your office’s carbon footprint without a capital project or a portfolio overhaul, occupancy is the lever, and it’s one most organizations still aren’t pulling.

ESG Deadlines are Looming 

The EU’s Energy Performance of Buildings Directive entered into force in May 2024 and sets zero-emission as the standard for new buildings. As of July, the EU Commission is starting infringement procedures against member states who haven’t yet included it in national law. 

The EU’s Corporate Sustainability Reporting Directive also brought the first wave of companies into mandatory sustainability reporting for FY2024, with those reports published in 2025. Since then, the EU has hit pause: a 2025 “stop-the-clock” directive pushed back reporting for the next waves of companies, and a proposed Omnibus simplification package would narrow the rule’s scope to companies with more than 1,000 employees. Large CRE portfolios, the ones with the most emissions to report and the most capital at stake, are still in scope. 

Deloitte’s review of FTSE 100 annual reports found that 69 of the 100 UK-listed companies restated their climate metrics last year, up from 46 the year before. Three-quarters of those metrics were in the Scope 3 , the category that typically holds your real estate operational emissions. That’s why credible occupancy data matters if you want your reporting to hold up. 

And even though the UK has pushed back mandatory minimum efficiency ratings of EPC-B by a year to 2031, the time to build your organization’s carbon footprint reduction muscle is now, before a looming deadline forces the issue. 

In this post, we’ll cover five ways to use occupancy data to reduce your office’s carbon footprint. 

1) Measure occupancy from every available data source for complete visibility into footprint reduction opportunities. 

Most CRE leaders only have partial occupancy visibility across the portfolio. How can we confidently say most? Well, 92% use badge swipe data as their main method of measuring office space utilization according to JLL’s most recent occupancy benchmarking report. A further 90% claim space utilization is their most important planning metric. 

Badge swipe data is valuable, but only tells you what people do as a binary – in the office or not in the office. Badge swipes don’t provide visibility into how people are using zones and floors once they’re in the office. And most importantly for carbon reduction purposes, badge data alone doesn’t pinpoint opportunities for cutting energy use over specific time frames. 

Measuring occupancy from a wider variety of data sources solves this problem. WiFi signals give granularity into specific areas. Occupancy sensors give more precision in enclosed spaces. Booking systems show how efficiently your meeting room portfolio is used. The accurate picture comes from combining all four into a single view of how each zone and floor is actually used over time.

2) Identify under and over utilized workspaces and cut energy use. 

Mid-week attendance clumping (yes we’re trademarking that phrase) is the hybrid status quo. Everyone shows up Tuesday, Wednesday and Thursday and floors and buildings empty out the rest of the week.

The environmental and monetary consequence of this pattern is heating and servicing a full-capacity space for three day,s and a mostly empty one for two. Even if you visually confirm your workplace’s attendance clumping habits, you lack the data to make decisions you can justify in a boardroom. 

That’s where tracking utilization data from the wider variety of sources in step one comes into play. 

Once you’ve done your measuring (which should be continuous), you have two options. 

One is to use team anchor days and hybrid policy changes to spread attendance more evenly across the week. 

The other is to temporarily close spaces when the data says they’re massively underutilized. 

For example, a floor with less than 5% utilization rate on Fridays could be closed on that day only. The few brave souls who usually venture onto that floor could be reallocated to other floors by managing occupancy.

Replicating this across multiple days and across a large corporate real estate portfolio, the reduction in energy use really starts to add up.

Radboud University in the Netherlands is a good example of what that looks like in practice. Facing budget pressure across a 41-building, seven-faculty campus, the university deployed HubStar’s PresenceIQ across its ten most critical buildings, combining sensor data in smaller lecture rooms with WiFi analytics for larger spaces. With that data in hand, Radboud closed five buildings over the Christmas holidays and kept a single building open for the few people who needed access, reducing carbon emissions and saving 55,000 euros in the process.

3) Use workplace booking tools to slash hidden waste and emissions. 

Inefficient use of workplace resources on the daily can sneakily snowball your organization’s carbon footprint. Using larger meeting rooms for only a few people is a common culprit here. Most of the time this is unintentional  – if a meeting room is free, someone will call dibs even if it’s a massive boardroom for a three person meeting where two are dialing in remotely. 

That creates excess use of lighting, heating, cooling and ventilation. The TV is switched on for a full two hours and the room needs cleaning afterwards. In a scenario like this, a two-person pod or small meeting room would have sufficed.

Workplace scheduling tools can reduce emissions here by matching up employees with the best spaces for their needs, not just in terms of size, but also features like A/V equipment, soundproofing and informal versus formal layouts. 

That’s a double win – fewer emissions and a better workplace experience since people can reserve the resources they need in advance. 

Usage analytics from booking systems and occupancy sensors also provide the data to rightsize your organization’s meeting room portfolio to reflect average meeting size, which these days tends to be just two or three. According to Hubstar’s Hybrid Occupancy Benchmarking Index, rooms with a capacity of over 17 are only 12% full when in use. 

Workplace scheduling can also cut emissions from lighting and save employees from the fluorescent big light hell by taking advantage of natural lightning. Meeting rooms on the east side of the office could be bookable in the morning, for instance, and meeting rooms on the west side could be bookable in the afternoon.

4) Rightsize use of facilities management and services.

Facilities management falls solidly into the Scope 3 emissions category.  FM teams can make a big dent in an office’s carbon footprint by rightsizing servicing of workspaces depending on occupancy levels.

Maintenance, repairs and servicing workspaces are all carbon intensive but at varying levels. 

Repairs are costlier than maintenance, both for the business and for the environment. Proactive and regular inspection of equipment makes it less likely FM teams will have to make repairs that incur a higher environmental cost.

On the flipside, equipment in heavily occupied areas of the office is more likely to need repair. By increasing inspection frequency in areas with higher utilization rates, FM teams can reduce the risk of equipment needing sudden repairs.

Similarly, by tracking workplace occupancy and overlaying this with floor plans, you can visualize which areas your janitorial team needs to pay the most attention to and which areas they can service less frequently.

The same is also true for other services like restocking vending machines and catering. By looking at occupancy patterns and trends over time, you can predict how much food employees will want.

That means less spend on catering and vending, less food waste and a reduced carbon footprint.

5) Predict occupancy to reduce CRE portfolio size.

Occupancy data is the strongest evidence a CRE team has for the biggest footprint reduction lever on the table: how much space the organization actually needs. Consolidating leases, subletting a floor, or repurposing underused space all carry real carbon and cost savings, and they’re decisions that should be made with confidence rather than guesswork. 

On the flip side, what might seem like a cost-effective decision to downsize could end up increasing carbon footprint if the environmental cost of office space skyrockets. A portfolio reduction that leaves employees fighting for desks and meeting rooms hurts experience, and it tends to push per-person energy and servicing costs back up. The goal is the right amount of space for real demand. 

Pro-tip: invest in an occupancy intelligence tool that predicts occupancy and gives you prescriptive suggestions on how to optimize your space around it, like HubStar’s PresenceIQ.