UK Building Reference Tables

96 quick-reference tables for UK building materials, dimensions, and standards. Bookmark these for the job site.

Concrete Mix Ratios

Standard UK concrete mix ratios explained with quantities per cubic metre and guidance on when to use each.

Insulation U-Values

Part L target U-values for walls, floors, roofs and windows with insulation thicknesses to achieve compliance.

UK Brick Dimensions

Standard UK brick sizes, coordinating dimensions and bricks per square metre for common bond patterns.

UK Cable Sizes

BS 7671 cable sizes and current ratings for common UK domestic circuits and installations.

UK Plasterboard Sizes

All standard UK plasterboard sizes, thicknesses, weights and types including fire-rated and moisture-resistant boards.

UK Timber Sizes

Standard UK timber sizes in CLS and regularised with metric and imperial equivalents.

UK Pipe Sizes

Standard UK plumbing and heating pipe sizes in copper, plastic and steel.

UK Screw and Fixing Sizes

UK screw gauge sizes, lengths and pilot hole diameters for wood, masonry and metal fixings.

UK Block Sizes

Standard UK concrete block sizes, weights and blocks per m² by type.

Part L 2021 U-Value Targets

Part L 2021 target U-values for all building elements with notional dwelling values.

BS 7671 Domestic Circuit Guide

BS 7671 domestic circuit specifications: cable sizes, MCB ratings and protective devices.

Mortar Mix Ratios

Standard mortar mix ratios for bricklaying, blockwork, rendering and pointing.

Radiator BTU Output Table

Radiator BTU output reference by size and type for heating system design.

Roof Tile Coverage Rates

Roof tile coverage rates per m² by tile type with batten gauge.

Paint Coverage Rates

Paint coverage rates in m² per litre by paint type and surface.

Skip Size Guide

Skip sizes from mini to RoRo with volume, weight limits and typical uses.

Drainage Pipe Sizes and Falls

Drainage pipe sizes and minimum fall gradients for foul and surface water.

Fixings Guide by Wall Type

Fixing types and pull-out loads by wall material: brick, block, plasterboard, timber and concrete.

Part B Fire Resistance Ratings

AD-B fire resistance periods: 30, 60, 90, 120 min ratings by building type for walls, floors, doors and structural elements.

Part B Unprotected Areas

AD-B boundary distance calculations, permitted unprotected areas, and methods 1-4 for external wall fire spread assessment.

Part E Acoustic Ratings

AD-E sound insulation requirements: airborne DnT,w+Ctr and impact L'nT,w targets for separating walls and floors.

Part E Sound Reduction

Part E compliant wall and floor constructions: Robust Details types, Rw ratings, and specifications for separating elements.

Part F Ventilation Rates

AD-F ventilation rates: Systems 1-4, kitchen and bathroom extract rates, background ventilator sizing, and purge ventilation.

Part F Extract Fan Requirements

Part F extract fan sizing by room, noise limits, duct length derating, timer requirements, and humidity sensor options.

Part G Hot Water Standards

AD-G hot water safety: storage at 60°C, TMV max 48°C at bath outlets, Legionella prevention, unvented cylinder G3 notification.

Part H Drainage Gradients

AD-H drainage gradients: minimum falls for foul and surface water pipes, inspection chamber spacing, and bedding classes.

Part J Flue Sizing

AD-J flue sizes by appliance type, terminal positions, clearances from openings, chimney heights, and hearth specifications.

Part K Stair Dimensions

AD-K stair dimensions: max rise 220mm, min going 220mm, pitch max 42°, headroom 2.0m, handrail and guarding heights.

Part L U-Value Targets History

Part L U-value requirements from 2006 to 2021: walls, floors, roofs, windows and doors targets by edition year.

Part L Air Permeability

Part L air permeability: target 8 m³/h.m² at 50 Pa, testing requirements, common leakage paths, and ventilation implications.

Part M Door Widths

AD-M door widths: minimum 775mm clear for new builds, approach spaces, and M4(1) M4(2) M4(3) accessibility categories.

Part M Ramp Gradients

AD-M ramp gradients: max 1:12 for 2m going, 1:15 for 5m, 1:20 for 10m, with landing sizes and handrail heights.

Part O Overheating Limits

AD-O overheating: glazing area limits by orientation, cross-ventilation requirements, shading factors, and TM59 criteria.

Part P RCD Requirements

AD-P and BS 7671 RCD protection: 30mA requirements for socket circuits, bathrooms, outdoors, RCD types, and notification.

Part Q Security Standards

AD-Q security: PAS 24:2016 door and window standards, letter plate specs, and door hardware for new dwellings in England.

Part S EV Charging Requirements

AD-S EV charging: 1 charge point per dwelling with parking, 1 per 5 commercial spaces, 7kW Mode 3 minimum specs.

UK Nail Sizes

Common UK nail types and sizes — round wire, lost head, ring shank, masonry, clout — with gauges, lengths and uses.

UK Anchor Bolt & Wall Plug Sizes

UK wall plug colours and sizes, rawlbolts, sleeve anchors and chemical anchors with drill hole sizes and load ratings.

UK Hinge Sizes

Butt hinges, parliament hinges and rising butt hinges with sizes by door weight and fire door requirements.

UK Joist Hanger Sizes

Standard joist hanger sizes for 47 mm and 75 mm timber with masonry and timber-to-timber types and safe working loads.

UK Timber Connector Sizes

Framing anchors, truss clips, joist straps and restraint straps with sizes, fixing specs and BS EN 14545 references.

UK Plywood & OSB Grades

Structural plywood and OSB grades, thicknesses, moisture classes and applications for UK construction.

UK MDF & Chipboard Sizes

Standard MDF and chipboard sheet sizes, thicknesses, grades including moisture-resistant P5 and applications.

UK Decking Board Sizes

Softwood and composite decking board sizes, profiles, lengths and fixing centres for UK garden decking.

UK Lintel Sizes

Steel lintels, concrete lintels and timber lintels with span tables, bearing requirements and cavity widths.

UK Cavity Tray Sizes

Cavity tray DPC types, widths, weep hole spacing and material specifications for UK cavity wall construction.

UK DPC Specifications

DPC types, widths and placement rules per Approved Document C for UK building construction.

UK Brick Types

Facing, engineering (Class A, B), common, London stock and Fletton bricks with strength and frost resistance.

UK Block Types

Dense, lightweight aggregate and aerated concrete blocks with compressive strengths and thermal conductivity.

UK Airbrick Sizes

Standard airbrick sizes, terracotta and plastic types, ventilation rates and installation requirements.

UK Copper Pipe Sizes

BS EN 1057 copper pipe sizes from 8–54 mm with outside diameters, wall thicknesses and working pressures.

UK Plastic Pipe Sizes

Speedfit, Hep2O, barrier pipe and PEX sizes with copper equivalents and temperature/pressure ratings.

UK Push-Fit Compatibility

JG Speedfit, Hep2O and Polypipe push-fit compatibility guide with sizes, inserts and pressure ratings.

UK Trap Sizes

P-trap, S-trap, bottle trap and running trap sizes for basins, baths, showers and WCs with depth of seal.

UK Soil Pipe Sizes

110 mm, 82 mm and 160 mm soil pipe sizes with connection types, gradient requirements and SVP heights.

UK Guttering Profiles

Half-round, square-line, ogee and deep-flow gutter profiles with sizes, flow capacities and bracket spacing.

UK Circuit Breaker Types

MCB types B, C, D curves, RCBO, RCD types A, AC, F with ratings from 6A–63A per BS 7671.

UK Consumer Unit Sizes

Consumer unit sizes from 6 to 24 ways, split load vs dual RCD vs RCBO board configurations.

UK Cable Trunking Sizes

Mini and maxi trunking sizes with cable fill capacities, compartment options and fixing centres.

UK Conduit Sizes

20, 25 and 32 mm conduit in PVC and galvanised steel with cable fill calculations and bend radius.

UK Insulation Lambda Values

Thermal conductivity (lambda) values for mineral wool, PIR, EPS, XPS, phenolic, wood fibre and natural fibres.

UK Vapour Resistance Values

Vapour resistivity for common building materials: plasterboard, OSB, PIR, breather membranes and VCLs.

UK Tile Adhesive Coverage

Tile adhesive coverage rates by tile size and substrate for walls and floors with notch trowel sizes.

UK Grout Coverage Rates

Grout quantities by tile size and joint width in kg/m² for 100x100 to 600x600 tiles, 2–10 mm joints.

UK Sealant Types

Silicone, acrylic, polyurethane, hybrid and butyl sealant types with cure times and applications.

UK Adhesive Types

PVA, grab, contact, epoxy, construction and tile adhesives with uses, cure times and working temperatures.

Wire Colour Codes — Old vs New

UK wiring colour codes old vs new. Red/black to brown/blue changeover for single-phase and three-phase per BS 7671.

Cable Ampacity Table

Current carrying capacity by cable size, installation method and insulation type per BS 7671 Tables 4D1A-4D5A.

Voltage Drop Coefficients

mV/A/m voltage drop values for common cable sizes per BS 7671 Tables 4D1B-4D5B.

Earth Electrode Resistance

Target earth electrode resistance values for TT systems, soil resistivity by type and testing methods.

BSP Pipe Thread Sizes

BSP parallel and taper thread sizes from 1/8 to 2 inch with TPI, major diameter and tapping drill sizes.

Water Velocity Standards

Maximum water velocities by pipe material for UK plumbing and heating. Noise thresholds and water hammer prevention.

Boiler Flue Temperature Ranges

Flue gas temperatures by boiler type and implications for flue material selection — plastic vs metal.

Joist Span Tables — C16 and C24

Maximum clear spans for C16 and C24 floor joists at 400mm and 600mm centres per TRADA span tables.

Rafter Span Tables

Maximum rafter spans for C16 and C24 timber at common pitches with purlin sizes and roof covering weights.

Beam Deflection Limits

Maximum deflection limits for beams and floors per Eurocodes. L/250, L/360 limits with steel beam section properties.

Notching and Drilling Rules

Joist notching and drilling rules per Approved Document A and BS 8103. Maximum depths, diameters and permitted zones.

Brick Bond Patterns

UK brick bond patterns: stretcher, Flemish, English, English garden wall and stack bond with structural implications.

Mortar Suction Rates

Initial Rate of Absorption targets for brickwork, testing methods, wetting requirements and bond strength effects.

Movement Joint Spacing

Movement joint spacing for clay brick, concrete block and calcium silicate masonry with width and sealant details.

Weep Hole Spacing

Weep hole spacing at DPC and cavity tray levels. Types, positions and maximum spacing for UK cavity walls.

Adhesive Coverage Rates

Coverage rates for tile adhesive, PVA, grab adhesive, wood glue, epoxy and flooring adhesives per m².

Drying Times Between Coats

Drying and curing times for paints, plasters, screeds and concrete. Recoat intervals and full cure times.

Ventilation Rates by Room

Extract ventilation rates by room type per Approved Document F 2021. Intermittent and continuous extract rates.

Duct Sizing Tables

Duct sizes for domestic ventilation by flow rate and velocity. Round, rectangular, flexible vs rigid comparison.

BS 7671 18th Edition Changes

Key changes from 17th to 18th Edition wiring regulations including AFDD, SPD, RCD and EV charging requirements.

Metric to Imperial Length

mm/cm/m to inches/feet/yards conversions with common UK construction lengths in both units.

Metric to Imperial Area

Square metres to square feet, acres to hectares with common UK room sizes in both units.

Metric to Imperial Volume

Cubic metres to cubic feet, litres to UK and US gallons. Common construction volumes in both units.

Metric to Imperial Weight

Kilograms to pounds/stones, tonnes to tons. Common UK construction material weights.

Pressure Unit Conversions

Bar, psi, kPa, mbar and metres head conversions with common UK water and gas pressure references.

Flow Rate Conversions

l/s, l/min, m³/h and gallons/min conversions with common UK plumbing and ventilation flow rates.

Temperature Conversions

Celsius to Fahrenheit conversions with UK plumbing, heating and construction reference temperatures.

Material Density Reference

Density in kg/m³ for concrete, timber, metals, aggregates, insulation, masonry and soils.

BS 5534 Wind Zones

UK wind zones for slating and tiling per BS 5534. Basic wind speed, site exposure and fixing requirements.

Competent Person Schemes

UK competent person schemes for building regulations self-certification: FENSA, Gas Safe, NICEIC, NAPIT, HETAS, MCS.