Hotel Stay Emissions
A night in a hotel is not a line item a traveller controls. The guest books a room; the building runs its boilers, chillers, kitchens, lifts, pool pumps, and laundry regardless of whether one bed or two hundred are occupied. Attributing a slice of that whole-building footprint to a single business trip is the entire problem hotel-stay accounting has to solve — and it cannot be solved by metering a guest’s behaviour, because the guest meters nothing.
The Hotel Carbon Measurement Initiative exists to make that attribution consistent: one defined boundary, one allocation rule, one unit — the occupied room-night — so that a stay booked in Lagos and a stay booked in Frankfurt are counted the same way and can be added together without double-counting or guesswork.
Hotel-stay emissions are room-nights multiplied by a per-room-night carbon intensity, reported under GHG Protocol Scope 3 Category 6. The intensity comes from a property’s own HCMI figure where available, otherwise a benchmark by country or hotel class.
This page covers hotel-stay emissions accounting — the methodology that converts business-travel accommodation into reportable Scope 3 Category 6 emissions. It covers why a room-night needs its own measurement basis, what the Hotel Carbon Measurement Initiative includes and deliberately excludes, the reported-to-estimated data hierarchy that decides which emission factor a stay earns, the core room-night calculation and its area-based variant, how to choose between a property’s own HCMI figure and a DEFRA or Cornell benchmark intensity, three audit-record worked examples, and the boundary, allocation, governance, and disclosure rules that let an assurance reviewer sign the result. It sits alongside the air-travel methodology as the second major component of a complete Category 6 inventory, and falls back to the spend-based approach only where no activity data exists.
Why Hotel Stays Need a Dedicated Methodology
Business travel is GHG Protocol Scope 3 Category 6, and within it accommodation is routinely the second-largest line after air travel. Unlike a fuel burn or a metered kilowatt-hour, a hotel stay produces no activity signal the reporting company can read directly: the traveller does not meter the room, and the hotel’s energy, water, refrigerant, and laundry consumption are shared across every guest, every function room, and every back-of-house operation simultaneously. The reporting company holds only two facts with confidence — how many rooms were booked, and for how many nights.
Where this sits in Scope 3
Category 6 captures emissions from the transportation and accommodation of employees for business purposes, in vehicles or facilities the reporting company neither owns nor controls. Accommodation is explicitly in scope. The emissions are the hotel’s operational footprint — the building’s Scope 1 combustion and refrigerant losses plus its Scope 2 purchased energy — re-counted as the reporting company’s Scope 3. This is a deliberate handover: what is the hotel’s direct emission is the guest company’s indirect emission, and the room-night is the unit that carries it across the boundary.
Why a room-night is not a kilowatt-hour
The defining difficulty is allocation. A hotel’s total annual footprint must be divided among the things that drove it before any single stay can be priced. HCMI’s answer is to normalise the whole-building footprint to two denominators — the occupied room-night and the conditioned floor area — so that the same property yields one intensity for sleeping rooms and another for meeting and function space. Without that normalisation, a half-empty hotel would appear to emit far more per guest than a full one for reasons that have nothing to do with either guest’s behaviour, and totals from different properties could never be compared or summed.
The room-night is an allocation unit, not a measurement. Hotel-stay accounting does not measure what a guest emitted; it apportions a defined share of the building’s whole-operation footprint to the night the guest occupied. Everything in the methodology — the boundary, the occupancy normalisation, the intensity factor — exists to make that apportionment consistent and additive across properties.
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What HCMI Measures, and What It Leaves Out
The Hotel Carbon Measurement Initiative defines a fixed operational boundary so that every property computes the same scope. The boundary is what makes one hotel’s per-room-night figure comparable to another’s — the value is meaningless unless the inputs behind it are identical in kind.
The in-scope energy and utility sources
| Source | Treatment | In HCMI boundary? |
|---|---|---|
| On-site fuel combustion (gas, oil, LPG for heating, hot water, kitchens) | Scope 1 of the hotel → Cat 6 of the guest company | Yes |
| Purchased electricity | Scope 2 of the hotel; location- or market-based | Yes |
| Purchased heat, steam, or cooling (district energy) | Scope 2 of the hotel | Yes |
| Refrigerant and fugitive losses (chillers, cold rooms, AC) | Scope 1; mass-balance leakage | Yes |
| On-site renewable generation consumed on site | Reduces purchased energy; not double-counted | Yes |
| Outsourced laundry energy | Allocated where the hotel can obtain the data | Where available |
| Guest food and beverage (production emissions) | A separate, larger Scope 3 question for the hotel | No |
| Guest transport to and from the property | Counted elsewhere in the traveller’s Cat 6 | No |
| Construction, capital goods, embodied carbon | Hotel’s Cat 2 / Cat 1; not a stay emission | No |
The two output units
HCMI produces two intensities from the same boundary. The per-occupied-room-night figure carries sleeping-room stays — the unit a business traveller’s overnight booking consumes. The per-square-metre-per-hour (or per-delegate-day) figure carries meeting, conference, and function space, which a room-night cannot describe. A complete Category 6 accommodation total uses the room-night intensity for overnight stays and the area intensity for any separately booked function space, and never applies one where the other belongs.
Deliberate exclusions
HCMI intentionally stops at the building’s operational energy and refrigerants. Food and beverage, guest transport, and capital goods are excluded not because they are immaterial but because they belong to other categories or other reporting entities, and folding them into a per-room-night figure would make the figure non-comparable and prone to double-counting. A reporting company that wants food-related travel emissions accounts for them separately; it does not inflate the hotel intensity to capture them.
Do not add a guest’s meals, minibar, or airport transfer to the hotel-stay figure. The HCMI intensity is an operational-energy-and-refrigerant figure by definition; padding it with food or transport both double-counts against other Category 6 components and breaks comparability with every benchmark intensity, which were all computed on the narrow HCMI boundary.
The Data Hierarchy — Property Figure to Spend Proxy
Most reporting companies cannot obtain an HCMI figure for every property their employees stay in. The methodology therefore runs on a tiered data hierarchy, identical in spirit to the reported-to-estimated principle that governs financed emissions in the PCAF data quality score: object-specific reported data outranks a benchmark, and a benchmark outranks a spend proxy. Each rung is a defensible fallback, used only when the rung above is unavailable.
| Rung | Data character | Typical source | Quality |
|---|---|---|---|
| Property HCMI figure | The specific hotel’s own per-room-night intensity, computed on the HCMI boundary | Supplier disclosure; hotel sustainability report; booking-platform carbon data | 1 — Best |
| Class / brand benchmark | A benchmark intensity for the hotel’s class, region, or brand | Cornell HSBI by class and country (hotel_stay.cha.<iso3>.<class>) |
2 — Good |
| Country average | A national average per-room-night intensity | DEFRA per-country hotel factors (hotel_stay.<country>) |
3 — Estimate |
| Spend proxy | Accommodation expenditure × a sector emission intensity | Spend-based MRIO factors × accommodation spend | 4 — Fallback |
HCMI, HSBI, and DEFRA are different things
These three terms are routinely conflated, and keeping them apart is the conceptual key to the whole hierarchy. HCMI is a methodology — the rules a property follows to compute and allocate its own footprint to a room-night. HSBI (the Cornell Hotel Sustainability Benchmarking Index) is a benchmark dataset of typical intensities by hotel class and country, used when a property has not published its own HCMI figure. The DEFRA per-country factors are a coarser national-average dataset for the same purpose. A property running HCMI sits at the top rung; falling back to HSBI or DEFRA means substituting a benchmark for the property’s real figure, with the data quality dropping accordingly.
Record which rung each stay used, not just the resulting tonnes. A Category 6 accommodation total built mostly on country averages is a weaker number than one built on supplier HCMI figures, and an assurance reviewer will want to see the mix. Tracking the rung over reporting periods also shows whether the programme is genuinely improving its supplier data or simply re-stating estimates.
The Core Calculation
The arithmetic is deliberately simple; the judgement is entirely in the choice of intensity factor and the boundary behind it.
| Hotel-stay emissions |
|---|
| Stay emissions (kg CO₂e) = room-nights × per-room-night intensity (kg CO₂e/room-night) |
| room-nights = number of rooms × number of nights |
| Function-space emissions (kg CO₂e) = floor area (m²) × hours × per-m²-hour intensity |
The room-night formula
A traveller occupying one room for three nights consumes three room-nights; two colleagues in two rooms for the same three nights consume six. The intensity is applied per room-night regardless of how many people share a room, because the building’s energy use is driven by the conditioned, serviced, and cleaned room, not by its headcount. This is why hotel-stay emissions are counted per room booked, never per traveller.
The area / occupancy variant
Meeting and function space cannot be expressed as room-nights, so it is carried on the per-area intensity instead — floor area multiplied by hours of use and the property’s per-square-metre-hour figure. The occupancy normalisation that sits underneath both intensities is the property’s own: HCMI divides the whole-building footprint by occupied room-nights and conditioned area for the period, so a low-occupancy property correctly shows a higher per-room-night intensity. The reporting company inherits that normalised figure; it does not re-normalise for its own stay.
Multi-night, multi-room, and multi-property
Stays are additive within a single intensity basis. A trip spanning three properties in three countries is three separate calculations — each room-night block multiplied by the intensity appropriate to its property or country — then summed. The one rule that survives every combination: never blend a per-room-night intensity and a per-area intensity into a single multiplication, and never sum totals computed on incompatible bases (for example an market-based property figure and a location-based benchmark) without flagging the mismatch.
Choosing the Emission Factor
When no property-specific HCMI figure is available, the choice is between a Cornell HSBI class benchmark and a DEFRA country average. Both are live, current-applied references in the GreenCalculus MasterBrain and resolve at page-load time; both are quoted here on the per-room-night basis.
DEFRA per-country intensities
The DEFRA hotel factors give a single national-average intensity per country — the coarsest activity-data rung, appropriate when only the country of stay is known. They are published on the DEFRA CO₂e convention, which is AR5 GWP-100; this is by design and is not mixed with an AR6-basis corporate inventory total without disclosure. Representative current values:
The spread is large and physically real: a country’s hotel intensity is dominated by its grid carbon intensity and its heating and cooling load, so a coal-heavy grid in a hot or cold climate produces a per-room-night figure several times that of a hydro- or nuclear-heavy grid in a mild one. This is exactly why the country average is a weak rung — it averages across a property population that varies enormously — and why a property HCMI figure or a class benchmark is preferred wherever obtainable.
Cornell HSBI by class and region
The Cornell HSBI rows refine the country average by hotel class, capturing the difference between an economy property and a full-service one within the same market. The contrast across markets is stark — a UK general-class intensity of 13.07 kg CO₂e/room-night [GreenCalculus hotel_stay.cha.gbr.general · CHA HOTEL 2024 · v2026.284] against a Chinese general-class figure of 64.89 [GreenCalculus hotel_stay.cha.chn.general · CHA HOTEL 2024] and a UAE figure of 74.19 [GreenCalculus hotel_stay.cha.are.general · CHA HOTEL 2024] — driven by grid carbon intensity, cooling load, and water-heating demand. A US economy property sits at 13.53 kg CO₂e/room-night [GreenCalculus hotel_stay.cha.usa.economy · CHA HOTEL 2024]. Use the class benchmark over the country average whenever the hotel’s class is known.
The unit trap is the single most common error in hotel accounting. A per-room-night intensity and a per-square-metre-hour intensity are not interchangeable, and multiplying a room-night count by an area intensity (or vice versa) produces a number that is wrong by orders of magnitude while looking entirely plausible. Confirm the unit string on every factor before multiplying — the MasterBrain rows are explicit that hotel intensities are kg CO₂e per room.night.
Worked Examples — Audit Records
Three audit-record snapshots. All values are fixed as audit records: they reconcile to their stated inputs and must continue to reconcile regardless of future data-layer changes. The figures are illustrative dated snapshots and do not represent any specific named property or trip. The intensities used reproduce the MasterBrain values current at the last-reviewed date; a live calculation reads the same keys via the calculator’s JS runtime.
Example A — a country-average DEFRA stay
| Example A — three-night stay, Australia, country-average rung | Value |
|---|---|
| Rooms booked | 1 |
| Nights | 3 |
| Room-nights (1 × 3) | 3 |
| Data rung | Country average (no property or class figure available) |
| Intensity — Australia (DEFRA, AR5) | 35 kg CO₂e/room-night |
| Stay emissions (3 × 35) | 105 kg CO₂e |
Three room-nights at the Australian country-average intensity of 35 kg CO₂e/room-night give 105 kg CO₂e for the stay. The figure carries the country-average rung label — a defensible estimate, but the weakest activity-data rung; obtaining the property’s HCMI figure or its class benchmark would replace 35 with a property-specific number and improve the data quality without changing the room-night count.
Example B — a class benchmark from Cornell HSBI
| Example B — two rooms, two nights, US economy class | Value |
|---|---|
| Rooms booked | 2 |
| Nights | 2 |
| Room-nights (2 × 2) | 4 |
| Data rung | Class benchmark (hotel class known: US economy) |
| Intensity — US economy (Cornell HSBI 2024) | 13.5334 kg CO₂e/room-night |
| Stay emissions (4 × 13.5334) | 54.13 kg CO₂e |
Four room-nights at the US-economy class benchmark of 13.5334 kg CO₂e/room-night give 54.13 kg CO₂e (rounded to two decimals). Because two colleagues each took a room, the multiplier is four room-nights, not two — the building serviced two rooms for two nights regardless of one occupant per room. Had a single traveller taken one room for the same period, the count would be two room-nights and the total 27.07 kg CO₂e.
Example C — meeting-space area allocation
| Example C — a separately booked function room | Value |
|---|---|
| Function-room floor area | 120 m² |
| Hours of use | 8 |
| Property per-m²-hour intensity (illustrative, property-supplied) | 0.045 kg CO₂e/m²·hr |
| Function-space emissions (120 × 8 × 0.045) | 43.2 kg CO₂e |
| Counted on the room-night basis? | No |
A conference room of 120 m² used for eight hours at a property-supplied area intensity of 0.045 kg CO₂e/m²·hr produces 43.2 kg CO₂e. The per-area intensity here is an illustrative property-supplied figure, not a MasterBrain hotel factor — the hotel_stay.* rows are per-room-night and cannot be used for area allocation. This emission is reported alongside, never inside, any room-night total for the same trip; mixing the two bases in one multiplication is the unit trap in action.
A worked example holds its inputs and result fixed so it reconciles a year from now — that is why these numbers are recorded, not shortcoded. A live calculator reads the current MasterBrain intensity at run time, so if a future DEFRA or HSBI release changes the Australia or US-economy factor, the calculator’s output will move while these audit records stay put. Both behaviours are correct: the example documents what was true on the stated date; the calculator documents what is true today.
Boundary and Allocation Rules
The intensity factor already encodes most boundary decisions, but four allocation questions recur often enough to state explicitly.
Occupancy is the property’s, not yours
HCMI normalises the whole-building footprint by the property’s own occupied room-nights for the period. A low-occupancy property legitimately shows a higher per-room-night intensity. The reporting company inherits that figure and does not adjust it for its own single stay — re-normalising would break comparability with every other stay on the same basis.
Shared and back-of-house space is already inside
Lobbies, corridors, kitchens, plant rooms, and pools are part of the whole-building footprint HCMI allocates across room-nights and function area. They are not a separate line. Do not attempt to add a share of the pool or the lobby to a stay — the intensity already carries it.
Mixed-use properties split by denominator
A property that is part hotel, part serviced apartments, or part retail allocates its footprint across the relevant denominators before publishing a per-room-night figure. Where a property cannot separate the hotel operation, a benchmark intensity is the safer rung than a distorted property figure.
Market-based claims need a matching basis
A property reporting a market-based intensity that reflects purchased renewable energy is not directly comparable to a location-based benchmark. Where a stay uses a market-based property figure and the rest of the portfolio uses location-based benchmarks, report the bases separately or flag the mismatch — do not blend them into one average.
Edge Cases and Known Pitfalls
Per room, not per person
Hotel-stay emissions are counted per room-night, never per traveller. Two people sharing one room consume one room-night; two people in two rooms consume two. The building services the room, not the headcount. Counting per person double-counts shared rooms and triple-counts nothing useful.
The room-night vs area unit trap
A per-room-night intensity and a per-m²-hour intensity are never interchangeable. Multiplying room-nights by an area factor — or area by a room-night factor — yields a plausible-looking number wrong by orders of magnitude. Confirm the unit string before every multiplication.
Don’t pad the intensity with food or transport
The HCMI boundary is operational energy and refrigerants only. Meals, minibar, and airport transfers belong to other Category 6 components or other entities. Adding them both double-counts and breaks comparability with every benchmark, which were computed on the narrow boundary.
Class benchmark beats country average
Where the hotel’s class is known, the Cornell HSBI class benchmark is a better rung than the DEFRA country average, because it captures the within-market spread between economy and full-service properties. Drop to the country average only when class is unknown.
Watch the AR5 / AR6 basis
DEFRA-sourced hotel factors carry an AR5 GWP-100 basis by design; corporate inventories on this site default to AR6. The asymmetry is intentional and is not a defect — but do not sum AR5-basis and AR6-basis line items into a single total without disclosing the mixed basis.
Spend is the last resort, not the default
A spend-based proxy — accommodation expenditure times a sector intensity — is the weakest rung and is appropriate only when neither a property figure, a class benchmark, nor a country average is obtainable. Reaching for spend first because it is easy understates the achievable data quality.
A benchmark is not the property’s real figure
HSBI and DEFRA intensities are population averages. Using one does not mean the specific hotel emits that amount — it means a typical property of that class or country does. Where the supplier can provide its own HCMI figure, the benchmark should give way to it, and the data-quality rung should be recorded as improved.
Don’t blend incompatible property bases
Market-based and location-based property figures, or HCMI and spend-derived figures, sit on different bases. A single blended accommodation total across incompatible bases looks precise while combining things that are not strictly comparable. Report the segments separately or flag the mismatch.
Governance, Assurance, and Disclosure
Hotel-stay emissions roll up into the reporting company’s Scope 3 Category 6 total, which in turn sits inside the inventory boundary defined by the GHG Protocol Corporate Standard. Category 6 is a required disclosure under CSRD ESRS E1 for in-scope EU undertakings and is expected under IFRS S2 for ISSB-aligned filers and the CDP climate questionnaire. An assurance reviewer reads the data-quality mix before the tonnage: an accommodation total built mostly on country averages or spend proxies signals an estimate-heavy figure warranting closer scrutiny, while a shift toward supplier HCMI figures over time is evidence of a genuinely tightening inventory.
Run the following pre-flight before submitting a Category 6 accommodation total for assurance:
- Room-night count reconciles. Every stay’s room-nights equal rooms × nights, counted per room rather than per traveller, and reconcile to the underlying travel-booking records.
- Correct unit on every factor. Per-room-night intensities multiply room-nights; per-area intensities multiply floor-area-hours. No factor is applied to the wrong denominator.
- Data rung recorded per stay. Each stay carries its rung — property HCMI figure, class benchmark, country average, or spend proxy — and the evidence behind it.
- Best available rung used. A property HCMI figure is used where obtainable; a class benchmark where class is known; the country average only as a fallback; spend only as a last resort.
- Boundary respected. The intensity covers operational energy and refrigerants only; food, transport, and capital goods are not folded in.
- Bases not blended silently. Market-based and location-based figures, and AR5- and AR6-basis line items, are reported separately or the mixed basis is disclosed.
- Function space carried separately. Meeting and conference emissions use the area intensity and are reported alongside, not inside, room-night totals.
- Factor source and version documented. The DEFRA or Cornell HSBI release used is recorded so the intensities are reproducible against the correct edition.
The three assurance findings most specific to hotel accounting are the unit trap (room-night count multiplied by an area intensity), per-traveller instead of per-room counting, and an undocumented data-quality mix that makes an estimate-heavy total look as solid as a measured one. Lock all three in the methodology note: confirm units, count per room, and record the rung behind every stay.
What the Calculator Handles vs What You Decide
A calculator automates the multiplication and the roll-up. It cannot make the data-rung and boundary judgements that determine which intensity a stay actually earns.
The calculator handles
Multiplying room-nights by the selected intensity; reading the live DEFRA and Cornell HSBI factors from the MasterBrain at run time; summing stays across properties and countries on a consistent basis; carrying function space on the area intensity separately; and producing an audit trail showing each stay’s room-nights, intensity, data rung, and resulting tonnes.
You decide
Which data rung each stay genuinely sits on, based on what the supplier can provide; whether a property figure is available or a benchmark must stand in; whether a market-based property figure is comparable to the rest of the portfolio; that function space is carried separately; and that food, transport, and capital goods stay outside the hotel intensity.
Convert room-nights to Category 6 emissions across any country or hotel class, choose the right data rung per stay, and produce a full audit trail — alongside the air-travel component of the same business-travel inventory.
Standards Alignment
Five standards govern hotel-stay accounting and its disclosure consequences.
| Standard | Role for this methodology |
|---|---|
| Cornell HCMI / Hotel Carbon Measurement | Defines the operational boundary, the per-room-night and per-area allocation, and the benchmark intensities (Cornell HSBI) used when no property figure exists. The methodological foundation of every intensity on this page. |
| GHG Protocol Scope 3 Standard | Defines Category 6 Business Travel, which includes accommodation; sets the requirement to report hotel-stay emissions and the data-quality expectations behind them. |
| GHG Protocol Corporate Standard | Defines the reporting company’s inventory boundary into which Category 6 rolls up; the hotel’s operational emissions become the reporting company’s Scope 3. |
| CSRD ESRS E1 | EU mandatory climate disclosure; in-scope undertakings disclose material Scope 3 categories including business-travel accommodation and the underlying data quality. |
| IFRS S2 | ISSB climate-related disclosures; Category 6 forms part of the Scope 3 metric, with the data-quality basis qualifying the disclosed figure. |
Frequently Asked Questions
The Hotel Carbon Measurement Initiative is the standard methodology for computing a hotel’s operational carbon footprint and allocating it to a guest stay. It defines a fixed boundary — on-site fuel, purchased energy, and refrigerants — and normalises the whole-building footprint to two units: the occupied room-night for sleeping rooms and a per-area figure for meeting and function space. A business traveller’s accommodation emissions are the room-nights consumed multiplied by the property’s per-room-night intensity.
Multiply room-nights by a per-room-night carbon intensity. Room-nights equal the number of rooms times the number of nights, counted per room rather than per traveller. For example, three nights in one room at a 35 kg CO₂e/room-night country intensity give 105 kg CO₂e. Meeting and function space is carried separately on a per-square-metre-hour intensity, never on the room-night basis.
Scope 3 Category 6, Business Travel, under the GHG Protocol Scope 3 Standard. Category 6 covers transportation and accommodation of employees for business purposes in facilities the reporting company does not own or control, and accommodation is explicitly in scope. The hotel’s own operational emissions are re-counted as the reporting company’s indirect Scope 3.
HCMI is a methodology — the rules a property follows to compute and allocate its own footprint to a room-night. The Cornell Hotel Sustainability Benchmarking Index (HSBI) is a benchmark dataset of typical per-room-night intensities by hotel class and country, used as secondary data when a property has not published its own HCMI figure. A property running HCMI sits at the top of the data hierarchy; an HSBI benchmark is a fallback estimate.
Per room-night, never per traveller. The building’s energy use is driven by the conditioned and serviced room, not by how many people occupy it. Two colleagues sharing one room for two nights consume two room-nights; two colleagues in two rooms for two nights consume four. Counting per person double-counts shared rooms.
Use the best available rung. A property’s own HCMI figure is best; failing that, a Cornell HSBI class benchmark where the hotel’s class is known; failing that, a DEFRA country-average intensity; and only as a last resort a spend-based proxy from accommodation expenditure. Each rung down is a weaker estimate, so record which rung each stay used.
Because a hotel’s per-room-night footprint is dominated by its grid carbon intensity and its heating and cooling load. A property on a coal-heavy grid in a hot or cold climate emits several times more per room-night than one on a low-carbon grid in a mild climate. This is why a country average is a weak rung — it averages across a property population that varies enormously — and why a property or class figure is preferred.
Guest food and beverage, guest transport to and from the property, and construction and capital goods. These are excluded not because they are immaterial but because they belong to other Scope 3 categories or other reporting entities. Folding them into a per-room-night figure would break comparability with benchmarks and double-count against other Category 6 components.
The DEFRA-sourced per-country hotel factors carry an AR5 GWP-100 basis by design, consistent with the DEFRA convention. Corporate inventories on this site otherwise default to AR6. The asymmetry is intentional, but AR5-basis and AR6-basis line items should not be summed into one total without disclosing the mixed basis.
Function space cannot be expressed as room-nights, so it is carried on a per-square-metre-hour intensity: floor area times hours of use times the property’s area figure. It is reported alongside, never inside, any room-night total for the same trip. Multiplying a room-night count by an area intensity, or vice versa, is the most common and most damaging error in hotel accounting.