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Fire Safety & Part B Calculators

Fire doors, fire stopping, compartmentation, escape routes and Part B compliance calculators.

Fire Door Specification Calculator

Determine FD30/FD60 fire door specification with intumescent strip and hardware.

Fire Stopping Calculator

Calculate fire stopping materials by penetration type and wall/floor fire rating.

Fire Compartmentation Calculator

Calculate fire compartment maximum area and fire wall/door positions by building use.

Fire Escape Distance Calculator

Check maximum travel distances to fire exits by building type.

Fire Resistance Period Calculator

Determine fire resistance period from building height and purpose group per Table B3.

Fire Exit Width Calculator

Calculate fire exit width from occupancy numbers at 5mm per person.

Fire Damper Calculator

Calculate fire dampers at compartment duct penetrations with size matching.

Smoke Vent Calculator

Calculate AOV smoke vent size and free area for common stairs.

Passive Fire Protection Calculator

Calculate intumescent strips, cold smoke seals and door closer selection.

Fire Alarm Zone Calculator

Calculate BS 5839 fire alarm zones, detector count and sounder coverage.

Emergency Lighting Layout Calculator

Calculate BS 5266 emergency lighting spacing and battery duration.

Sprinkler System Calculator

Calculate BS 9251 residential sprinkler head count, pipe sizing and tank sizing.

Cavity Barrier Calculator

Calculate cavity barrier positions at party walls, 20m intervals and around openings.

External Wall Fire Rating Calculator

Determine external wall cladding requirements by building height.

HMO Fire Safety Calculator

Calculate HMO fire alarm grade, fire door locations and escape route widths.

Fire Mastic and Sealant Calculator

Calculate fire-rated mastic joint length and cartridge coverage per penetration.

Smoke Detector Layout Calculator

Calculate BS 5839-6 smoke detector grade, coverage area and ceiling height limits.

Fire Escape Signage Calculator

Calculate BS 5499 fire escape sign sizes from viewing distance and sign count.

Fire Risk Score Calculator

Calculate fire risk score from ignition sources, fuel load and detection quality.

External Fire Spread Calculator

Calculate unprotected area percentage by boundary distance per Approved Document B.

Loft Conversion Fire Safety Calculator

Calculate loft conversion fire safety requirements for protected stairway and alarms.

Commercial Fire Strategy Calculator

Calculate commercial fire strategy with travel distances, exit widths and sprinkler trade-offs.

Emergency Lighting Calculator

Calculate emergency lighting spacing and battery duration per BS 5266.

Fire Escape Window Calculator

Check Part B fire escape window requirements for loft habitable rooms.

24 free calculators in Fire Safety & Part B

Fire Safety & Part B Calculators for UK Construction

Fire safety is one of the most critical aspects of building design and construction in the UK. Approved Document B of the Building Regulations sets out comprehensive requirements for fire safety, covering means of escape, internal fire spread across linings and structure, external fire spread, and access for the fire service. Our calculators help architects, fire engineers, and building control professionals verify compliance with these essential requirements.

Following the Grenfell Tower tragedy and the subsequent Building Safety Act 2022, fire safety standards in England and Wales have been significantly strengthened. These tools help you calculate travel distances for means of escape, determine compartmentation requirements based on building use and height, specify fire doors with the correct FD rating, and design smoke ventilation systems that meet BS 9991 and BS 9999 standards. Each calculator references the latest regulatory framework including the Fire Safety (England) Regulations 2022.

Whether you're working on residential developments, commercial premises, or mixed-use buildings, accurate fire safety calculations are essential for Building Control approval and, more importantly, for protecting life. These tools support the work of fire risk assessors, passive fire protection installers, and contractors who need quick, reliable reference calculations on site.