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Lift-well pressurisation

Lift-shaft pressurisation: landing-door leakage (0.06 m² each, BS EN 12101-6) or the door gaps, shaft walls and vent, the landing doors open at the fire floor and the access level, the landing-door operating limit, the stack effect over the shaft height, injection points, relief, fan and riser.

NBC 2016 Part 4BS EN 12101-6:2005BS EN 12101-13:2022NFPA 92 (2021)NFPA 101:2021ASHRAE Handbook of Smoke Control Engineering (2012)

What it does

Landing doors0.06 m² per landing door (BS EN 12101-6 Table A.2) or the gaps incl. the meeting edge.
Doors closed and openΔP held with every door shut; air speed through the open door with the others at 10 Pa.
Door limitDesign ΔP against the landing-door operating limit from the lift maker.
Stack effectΔP over the height for summer and winter, injection points every 3 floors.
Fan and reliefDuty with duct leakage, static pressure, motor, barometric relief damper or VFD.
OutputsReport with worked steps, Excel, riser-diagram DXF, BOQ.

Checks it performs

PASS / CHECKDesign ΔP ≤ landing-door limit
PASS / CHECKΔP over the height within the band
PASS / CHECKInjection points
PASS / CHECKRelief damper area

Sample report

Also searched as

lift well pressurization calculation; lift shaft pressurisation fan sizing; elevator hoistway pressurization; lift landing door leakage 0.06 m2; NBC lift shaft pressurisation. The same calculation, the same clauses — one tool for fire fighting design under the Indian codes (NBC, IS, CPWD) or the international ones (IEC, NFPA, ASHRAE, EN).

Standards applied

ReferenceTitleUsed for
NBC 2016 Part 4National Building Code — Fire and life safetyOccupant load (Table 5), exit width (Table 22), travel distance (Table 21), stair widths
BS EN 12101-6:2005Smoke and heat control systems — Specification for pressure differential systems — KitsSystem classes A–F, design pressure differences and open-door air speeds, door-opening force, leakage areas of doors / windows (Annex A), calculation method
BS EN 12101-13:2022Smoke and heat control systems — Pressure differential systems (PDS) — Design and calculation methods, installation, acceptance testing, routine testing and maintenanceDesign and calculation of pressurised stairs, lobbies and lift wells; commissioning (pressure difference doors closed, air speed doors open)
NFPA 92 (2021)Smoke control systemsPressurisation and smoke-exhaust design and acceptance
NFPA 101:2021Life Safety CodeMeans of egress (international option)
ASHRAE Handbook of Smoke Control Engineering (2012)Klote, Milke, Turnbull, Kashef, Ferreira — Handbook of Smoke Control EngineeringFlow through leakage paths, wall / floor leakage ratios, stack effect in pressurised stairwells and lift shafts, door-opening force
BS 9999:2017Fire safety in the design, management and use of buildings — Code of practiceProtected stairs, fire-fighting shafts and lobbies, when pressurisation is used in place of natural ventilation
EN 81-72:2020Firefighters liftsFire-fighter lift features

Frequently asked

How do I use the Lift-well pressurisation calculator?

Open the tool, change the pre-filled example to your project, read the results, checks and worked steps as you type, then export the report, Excel and DXF.

Which codes and standards does the lift-well pressurisation follow?

It applies NBC 2016 Part 4, BS EN 12101-6:2005, BS EN 12101-13:2022, NFPA 92 (2021), NFPA 101:2021, ASHRAE Handbook of Smoke Control Engineering (2012) and others. Every result line shows the formula and the clause it comes from, and the report lists the standards applied.

What does it check?

Every run is marked PASS or CHECK against: Design ΔP ≤ landing-door limit; ΔP over the height within the band; Injection points; Relief damper area.

Is the calculator free to use?

Yes — running the calculation, reading the results, checks and clauses is free. One design credit unlocks the report, Excel and DXF exports for 30 days; the first design is free on sign-in.

Is this the same as a lift well pressurization calculation?

Yes. People also call it a lift shaft pressurisation fan sizing, a elevator hoistway pressurization, a lift landing door leakage 0.06 m2. It covers the same calculation under fire fighting design, with the Indian and international code regimes selectable.

Does it work with AutoCAD or ZWCAD?

Yes — with the free DesignLink CAD plugin the tool reads rooms, layers and selections from the open drawing and places its DXF output straight back into the plan; without the plugin you upload a DXF and download the result.

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