NHBC
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  • 1 Welcome
    • 1.1 Contact us
    • 1.2 What’s changed
  • 2 Introduction
    • 2.1 The Standards and Technical Requirements
    • 2.2 3D Models
  • 3 General
    • 3.1 Concrete and its reinforcement
      • 3.1.1 Compliance
      • 3.1.2 Provision of information
      • 3.1.3 Storage of materials
      • 3.1.4 Site-mixed concrete
      • 3.1.5 Ready-mixed concrete
      • 3.1.6 Concrete specification
      • 3.1.7 Admixtures
      • 3.1.8 Special types of concrete
      • 3.1.9 Design of reinforced concrete
      • 3.1.10 Installation of reinforcement
      • 3.1.11 Blinding concrete
      • 3.1.12 Formwork
      • 3.1.13 Before concreting
      • 3.1.14 Casting
      • 3.1.15 Curing
      • 3.1.16 Testing
      • 3.1.17 Glossary
      • Figure reference table
    • 3.2 Cold weather working
      • 3.2.1 Compliance
      • 3.2.2 External conditions
      • 3.2.3 Materials
      • 3.2.4 Concreting
      • 3.2.5 Masonry
      • 3.2.6 Rendering, plastering and screeding
      • 3.2.7 Admixtures
      • 3.2.8 Painting
    • 3.3 Timber preservation (natural solid timber)
      • 3.3.1 Compliance
      • 3.3.2 Durability
      • 3.3.3 Sitework
      • 3.3.4 Protection and storage
      • 3.3.5 Treatment of cut surfaces
      • 3.3.6 Compatibility with metal
      • 3.3.7 Further information
      • Figure reference table
  • 4 Foundations
    • 4.1 Land quality – managing ground conditions
      • 4.1.1 Compliance
      • 4.1.2 Initial Assessment – desk study (all sites)
      • 4.1.3 Initial Assessment – walkover survey (all sites)
      • 4.1.4 Initial Assessment – results
      • 4.1.5 Basic Investigation (sites where hazards are not identified or suspected)
      • 4.1.6 Detailed Investigation (sites where hazards are identified or suspected)
      • 4.1.7 Managing the risks (sites where hazards are found)
      • 4.1.8 Unforeseen hazards
      • 4.1.9 Documentation and verification
      • 4.1.10 Guidance for investigations
      • 4.1.11 Further information
      • Figure reference table
    • 4.2 Building near trees
      • 4.2.1 Compliance
      • 4.2.2 Provision of information
      • 4.2.3 Building near trees
      • 4.2.4 The effects of trees on shrinkable soils
      • 4.2.5 Foundations in all soil types
      • 4.2.6 Excavation of foundations
      • 4.2.7 Foundations in shrinkable soils
      • 4.2.8 Design and construction of foundations in shrinkable soils
      • 4.2.9 Foundation depths for specific conditions in shrinkable soils
      • 4.2.10 Heave precautions
      • 4.2.11 New drainage
      • 4.2.12 Method of assessment of foundation depths using charts
      • 4.2.13 Method of assessment of foundation depths using tables
      • 4.2.14 Worked example
      • 4.2.15 Further information
    • 4.3 Strip and trench fill foundations
      • 4.3.1 Compliance
      • 4.3.2 Provision of information
      • 4.3.3 Ground conditions
      • 4.3.4 Hazardous ground
      • 4.3.5 Setting out
      • 4.3.6 Services and drainage
      • 4.3.7 Safe transmission of loads
      • 4.3.8 Sloping ground and stepped foundations
      • 4.3.9 Excavations
      • 4.3.10 Reinforcement
      • 4.3.11 Concrete
      • 4.3.12 Movement joints
      • 4.3.13 Construction joints
    • 4.4 Raft, pile, pier and beam foundations
      • 4.4.1 Compliance
      • 4.4.2 Provision of information
      • 4.4.3 Site conditions
      • 4.4.4 Hazardous ground
      • 4.4.5 Services and drainage
      • 4.4.6 Safe transmission of loads
      • 4.4.7 Construction
      • 4.4.8 Engineer checks
      • 4.4.9 Compressible materials
      • 4.4.10 Reinforcement
      • 4.4.11 Concrete
      • 4.4.12 Movement joints
      • 4.4.13 Resistance to moisture
    • 4.5 Vibratory ground improvement techniques
      • 4.5.1 Compliance
      • 4.5.2 Hazardous sites and ground hazards
      • 4.5.3 Desk study and site investigation
      • 4.5.4 Confirmation of suitability for treatment
      • 4.5.5 Suitability of ground conditions
      • 4.5.6 Compatibility of the ground, design and treatment
      • 4.5.7 Acceptable methods
      • 4.5.8 Materials for use as fill
      • 4.5.9 Granular material
      • 4.5.10 Sitework
      • 4.5.11 Adjacent excavations
      • 4.5.12 Verification of completed treatment
    • 4.6 Engineered fill
      • 4.6.1 Compliance
      • 4.6.2 Provision of information
      • 4.6.3 Hazardous sites and ground hazards
      • 4.6.4 Desk study and ground investigation
      • 4.6.5 Suitability of ground conditions
      • 4.6.6 Materials for use as engineered fill
      • 4.6.7 Design and specification of earthworks
      • 4.6.8 Compatibility of fill with foundations, infrastructure and external works
      • 4.6.9 Acceptable methods of earthworks filling
      • 4.6.10 Site work
      • 4.6.11 Adjacent excavations
      • 4.6.12 Verification of engineered fill
      • 4.6.13 Reporting
      • Figure reference table
  • 5 Substructure, Ground Floors, Drainage and Basements
    • 5.1 Substructure and ground-bearing floors
      • 5.1.1 Compliance
      • 5.1.2 Provision of information
      • 5.1.3 Transfer of loads
      • 5.1.4 Ground conditions
      • 5.1.5 Services and drainage
      • 5.1.6 Ground below fill
      • 5.1.7 Fill below floors
      • 5.1.8 Infill up to 600mm deep
      • 5.1.9 Materials used for fill
      • 5.1.10 Harmful or toxic materials
      • 5.1.11 Regulatory solutions
      • 5.1.12 Walls below the DPC
      • 5.1.13 Durability
      • 5.1.14 Mortar
      • 5.1.15 Wall ties
      • 5.1.16 Blinding
      • 5.1.17 Ground floor slab and concrete
      • 5.1.18 Laying the ground-bearing floor slab
      • 5.1.19 Damp proof course
      • 5.1.20 Damp proofing concrete floors
      • 5.1.21 Thermal insulation
      • 5.1.22 Installation of insulation
      • 5.1.23 Further information
      • Figure reference table
    • 5.2 Suspended ground floors
      • 5.2.1 Compliance
      • 5.2.2 Provision of information
      • 5.2.3 Contaminants
      • 5.2.4 Proprietary systems
      • 5.2.5 Transfer of loads: concrete floors
      • 5.2.6 Reinforced concrete
      • 5.2.7 Construction of suspended concrete ground floors
      • 5.2.8 Transfer of loads: timber floors
      • 5.2.9 Thermal insulation and thermal bridging
      • 5.2.10 Damp proofing and ventilation
      • 5.2.11 Floor finishes
      • 5.2.12 Floor decking
    • 5.3 Drainage below ground
      • 5.3.1 Compliance
      • 5.3.2 Provision of information
      • 5.3.3 Preliminary work
      • 5.3.4 Foul and surface water disposal
      • 5.3.5 Drainage system performance
      • 5.3.6 Ground water drainage
      • 5.3.7 Design to avoid damage and blockages
      • 5.3.8 Durability
      • 5.3.9 Septic tanks and cesspools
      • 5.3.10 Septic tank outputs
      • 5.3.11 Surface water soakaways
      • 5.3.12 Component requirements
      • 5.3.13 Excavation
      • 5.3.14 Protection of pipework
      • 5.3.15 Laying pipework
      • 5.3.16 Protection of work
      • 5.3.17 Testing
    • 5.4 Waterproofing of basements and other below ground structures
      • 5.4.1 Compliance
      • 5.4.2 Provision of information
      • 5.4.3 Waterproofing
      • 5.4.4 Ground conditions
      • 5.4.5 Structural stability
      • 5.4.6 Design considerations
      • 5.4.7 Waterproofing systems
      • 5.4.8 Handling, storage and protection
      • 5.4.9 Buried podiums
      • Figure reference table
  • 6 Superstructure (excluding roofs)
    • 6.1 External masonry walls
      • 6.1.1 Compliance
      • 6.1.2 Provision of information
      • 6.1.3 Structural design
      • 6.1.4 Fire resistance
      • 6.1.5 Acoustic resistance
      • 6.1.6 Exposure
      • 6.1.7 Thermal insulation
      • 6.1.8 Concrete blocks
      • 6.1.9 Bricks
      • 6.1.10 Stone masonry
      • 6.1.11 Construction of masonry walls
      • 6.1.12 Lintels
      • 6.1.13 Materials suitable for mortar
      • 6.1.14 Mortar
      • 6.1.15 Render
      • 6.1.16 Cladding
      • 6.1.17 DPCs and cavity trays
      • 6.1.18 Wall ties, bed joint reinforcements and windposts
      • 6.1.19 Handling materials
      • 6.1.20 Protection of the works during construction
      • Figure reference table
    • 6.2 External timber framed walls
      • 6.2.1 Compliance
      • 6.2.2 Provision of information
      • 6.2.3 Design checking and certification
      • 6.2.4 Load-bearing walls
      • 6.2.5 Fixing the frame
      • 6.2.6 Nails and staples
      • 6.2.7 Sheathing
      • 6.2.8 Differential movement
      • 6.2.9 Fire resistance
      • 6.2.10 Protection from moisture
      • 6.2.11 Timber preservation
      • 6.2.12 Air and vapour control layers
      • 6.2.13 Breather membranes
      • 6.2.14 Wall ties and fixings
      • 6.2.15 Insulation
      • Figure reference table
    • 6.3 Internal walls
      • 6.3.1 Compliance
      • 6.3.2 Provision of information
      • 6.3.3 Supporting load-bearing internal walls
      • 6.3.4 Masonry walls
      • 6.3.5 Load-bearing timber walls
      • 6.3.6 Fire resistance
      • 6.3.7 Sound insulation
      • 6.3.8 Partitions: internal non load-bearing
      • 6.3.9 Construction of timber partitions
      • 6.3.10 Construction of steel framed partitions
      • 6.3.11 Construction of proprietary systems
      • 6.3.12 Plasterboard
      • 6.3.13 Damp proof courses
      • 6.3.14 Components
      • Figure reference table
    • 6.4 Timber and concrete upper floors
      • 6.4.1 Compliance
      • 6.4.2 Provision of information
      • 6.4.3 Upper floor design
      • 6.4.4 Fire spread
      • 6.4.5 Sound insulation
      • 6.4.6 In-situ concrete floors and concreting
      • 6.4.7 Precast concrete
      • 6.4.8 Timber joist spans
      • 6.4.9 Timber joist performance
      • 6.4.10 Construction of timber floors
      • 6.4.11 Joists supported by intermediate walls
      • 6.4.12 Joists connected to steel
      • 6.4.13 Joists into hangers
      • 6.4.14 Timber joist and restraint strap
      • 6.4.15 Strutting
      • 6.4.16 Joists and openings
      • 6.4.17 Multiple joists
      • 6.4.18 Notching and drilling
      • 6.4.19 Floor decking
      • 6.4.20 Floating floors or floors between homes
    • 6.5 Steelwork
      • 6.5.1 Compliance
      • 6.5.2 Design guidance
      • 6.5.3 Steel grade and coatings
      • 6.5.4 Installation and support
      • 6.5.5 Padstones
      • 6.5.6 Connections
      • 6.5.7 Examples
      • Figure reference table
    • 6.6 Staircases
      • 6.6.1 Compliance
      • 6.6.2 Provision of information
      • 6.6.3 Fire precautions
      • 6.6.4 Lighting
      • 6.6.5 Glazing
      • 6.6.6 Structural design
      • 6.6.7 Headroom and width
      • 6.6.8 Design of steps
      • 6.6.9 Landings
      • 6.6.10 Guarding
      • 6.6.11 Handrails
      • 6.6.12 Staircases made from timber and wood-based products
      • 6.6.13 Concrete staircases
      • 6.6.14 Steel staircases
      • 6.6.15 Proprietary staircase units
      • 6.6.16 Protection
      • Figure reference table
    • 6.7 Doors, windows, and glazing
      • 6.7.1 Compliance
      • 6.7.2 Provision of information
      • 6.7.3 In-service performance
      • 6.7.4 Coupled door and window frame assemblies
      • 6.7.5 Glazing
      • 6.7.6 Security
      • 6.7.7 Timber doors and windows
      • 6.7.8 Non-timber doors and windows
      • 6.7.9 Ironmongery
      • 6.7.10 Material storage and protection
      • 6.7.11 Installation
      • 6.7.12 Completed work
      • Figure reference table
    • 6.8 Fireplaces, chimneys and flues
      • 6.8.1 Compliance
      • 6.8.2 Provision of information
      • 6.8.3 Solid fuel – fireplaces and hearths
      • 6.8.4 Solid fuel – combustion air
      • 6.8.5 Solid fuel – flue pipes
      • 6.8.6 Solid fuel – chimneys
      • 6.8.7 Solid fuel – outlets and terminals
      • 6.8.8 Gas – fireplaces and hearths
      • 6.8.9 Gas – combustion air
      • 6.8.10 Gas – flue pipes
      • 6.8.11 Gas – chimneys
      • 6.8.12 Gas – outlets and terminals
      • 6.8.13 Oil – fireplaces and hearths
      • 6.8.14 Oil – combustion air
      • 6.8.15 Oil – flue pipes
      • 6.8.16 Oil – chimneys
      • 6.8.17 Oil – outlets and terminals
      • 6.8.18 All – fireplaces and hearths
      • 6.8.19 All – fireplace surrounds
      • 6.8.20 All – flue pipes
      • 6.8.21 All – flue liners
      • 6.8.22 All – flues
      • 6.8.23 All – chimneys
      • 6.8.24 Masonry
      • 6.8.25 Mortar
      • 6.8.26 DPC
      • 6.8.27 Flashings
      • 6.8.28 Terminals
      • 6.8.29 Flue testing
      • 6.8.30 Further information
    • 6.9 Curtain walling and cladding
      • 6.9.1 Compliance
      • 6.9.2 Provision of information
      • 6.9.3 Certification
      • 6.9.4 Loads
      • 6.9.5 Support and fixings
      • 6.9.6 Durability
      • 6.9.7 Interfaces
      • 6.9.8 Insulation
      • 6.9.9 Damp proofing and vapour control
      • 6.9.10 Installation and tolerances
      • 6.9.11 Electrical continuity and earth bonding
      • 6.9.12 Maintenance
      • 6.9.13 Glazing, gaskets and sealants
      • 6.9.14 Cavity barriers and firestops
      • 6.9.15 Ventilation screens
      • 6.9.16 Handling and storage
      • 6.9.17 Curtain walling
      • 6.9.18 Rainscreen cladding
      • 6.9.19 Insulated render and brick slip cladding
    • 6.10 Light steel framed walls and floors
      • 6.10.1 Compliance
      • 6.10.2 Provision of information
      • 6.10.3 Structural certification
      • 6.10.4 Structural design of load-bearing floors and walls
      • 6.10.5 Structural design of infill walls
      • 6.10.6 Roofs
      • 6.10.7 Steel and fixings
      • 6.10.8 Detailing of steel joists
      • 6.10.9 Restraint
      • 6.10.10 Construction of load-bearing walls and external infill walls
      • 6.10.11 Interfaces with staircases
      • 6.10.12 Fixing floor decking and ceilings
      • 6.10.13 Other design issues
      • 6.10.14 Behaviour in relation to fire
      • 6.10.15 Acoustic performance
      • 6.10.16 Moisture control
      • 6.10.17 Insulation
      • 6.10.18 Air and vapour control layers
      • 6.10.19 Breather membranes
      • 6.10.20 Cladding, lining and sheathing boards
      • 6.10.21 Wall ties
      • 6.10.22 Services
      • 6.10.23 Further information
      • Figure reference table
    • 6.11 Render
      • 6.11.1 Compliance
      • 6.11.2 Provision of information
      • 6.11.3 Weather conditions
      • 6.11.4 Backgrounds
      • 6.11.5 Accommodation of movement
      • 6.11.6 Mixes
      • 6.11.7 Detailing
      • 6.11.8 Render onto board backgrounds
      • 6.11.9 Finishes
      • Figure reference table
  • 7 Roofs
    • 7.1 Flat roofs, terraces and balconies
      • 7.1.1 Compliance
      • 7.1.2 Provision of information
      • 7.1.3 Flat roof, terrace and balcony general design
      • 7.1.4 Drainage
      • 7.1.5 Flat roof, terrace and balcony structural design
      • 7.1.6 Timber structure and deck
      • 7.1.7 Concrete decks
      • 7.1.8 Profiled self-supporting metal roof decks
      • 7.1.9 Profiled self-supporting metal roofing
      • 7.1.10 Thermal insulation and vapour control
      • 7.1.11 Waterproofing layer and surface treatments
      • 7.1.12 Green and biodiverse (brown roofs) – including roof gardens
      • 7.1.13 Blue roofs
      • 7.1.14 Raised and buried podiums
      • 7.1.15 Detailing of flat roofs
      • 7.1.16 Accessible thresholds and upstands
      • 7.1.17 Metal balcony decking systems
      • 7.1.18 Parapets and guarding to terraces and balconies
    • 7.2 Pitched roofs
      • 7.2.1 Compliance
      • 7.2.2 Provision of information
      • 7.2.3 Design of pitched roofs
      • 7.2.4 Protection of trusses
      • 7.2.5 Durability
      • 7.2.6 Wall plates
      • 7.2.7 Joints and connections
      • 7.2.8 Restraint
      • 7.2.9 Bracing for trussed rafter roofs
      • 7.2.10 Strutting for site formed attic trusses and cut roofs that form a floor
      • 7.2.11 Support for equipment
      • 7.2.12 Access
      • 7.2.13 Dormer construction
      • 7.2.14 Underlay, sarking boards and sheets
      • 7.2.15 Ventilation, vapour control and insulation
      • 7.2.16 Fire-stopping and cavity barriers
      • 7.2.17 Battens
      • 7.2.18 Roof coverings
      • 7.2.19 Fixing tiles and slates
      • 7.2.20 Weathering details
      • 7.2.21 Valleys and hidden gutters
      • 7.2.22 Drainage
      • 7.2.23 Fascias and trim
      • 7.2.24 Spandrel panels in cold roofs
      • 7.2.25 Roof cassette systems
      • 7.2.26 Solar roof panels
      • Figure reference table
  • 8 Services
    • 8.1 Internal services
      • 8.1.1 Compliance
      • 8.1.2 Provision of information
      • 8.1.3 Water services and supply
      • 8.1.4 Cold water storage
      • 8.1.5 Gas services
      • 8.1.6 Electrical services
      • 8.1.7 Meter boxes
      • 8.1.8 Hot water services
      • 8.1.9 Unvented storage systems
      • 8.1.10 Soil and waste systems internal
      • Figure reference table
    • 8.2 Electrical generating technologies
      • 8.2.1 Solar photovoltaics (PV)
        • 8.2.1.1 Compliance
        • 8.2.1.2 Provision of information
        • 8.2.1.3 System design
        • 8.2.1.4 Building integration
        • 8.2.1.5 Fixing
        • 8.2.1.6 Access
        • 8.2.1.7 Electrical installation requirements
        • 8.2.1.8 Handling and storage
        • 8.2.1.9 Sequence of work
        • Figure reference table
      • 8.2.2 Wind turbines
        • 8.2.2.1 Compliance
        • 8.2.2.2 Provision of information
        • 8.2.2.3 System design
        • 8.2.2.4 Building integration
        • 8.2.2.5 Fixing
        • 8.2.2.6 Access
        • 8.2.2.7 Electrical installation requirements
        • 8.2.2.8 Handling and storage
        • 8.2.2.9 Sequence of work
        • Figure reference table
    • 8.3 Space heating systems
      • 8.3.1 Space heating
        • 8.3.1.1 Requirements
      • 8.3.2 Gas heating appliances
        • 8.3.2.1 Compliance
        • 8.3.2.2 Provision of information
        • 8.3.2.3 System design
        • 8.3.2.4 Building integration
        • 8.3.2.5 Fixing
        • 8.3.2.6 Access
        • 8.3.2.7 Electrical installation requirements
        • 8.3.2.8 Handling and storage
        • 8.3.2.9 Sequence of work
      • 8.3.3 Heat pumps
        • 8.3.3.1 Compliance
        • 8.3.3.2 Provision of information
        • 8.3.3.3 System design
        • 8.3.3.4 Pipes, insulation and protection from cold
        • 8.3.3.5 Ground collectors
        • 8.3.3.6 Building integration
        • 8.3.3.7 Fixing
        • 8.3.3.8 Access
        • 8.3.3.9 Electrical installation requirements
        • 8.3.3.10 Handling and storage
        • 8.3.3.11 Sequence of work
        • Figure reference table
      • 8.3.4 Biomass
        • 8.3.4.1 Compliance
        • 8.3.4.2 Clean air act
        • 8.3.4.3 Fuel storage
        • Figure reference table
    • 8.4 Ventilation
      • 8.4.1 Mechanical ventilation and heat recovery (MVHR)
        • 8.4.1.1 Compliance
        • 8.4.1.2 Provision of information
        • 8.4.1.3 System design
        • 8.4.1.4 Acoustics
        • 8.4.1.5 Building integration
        • 8.4.1.6 Ductwork
        • 8.4.1.7 Fixing and jointing of ductwork
        • 8.4.1.8 Access and operation
        • 8.4.1.9 Electrical installation requirements
        • 8.4.1.10 Handling and storage
        • 8.4.1.11 Commissioning and balancing
        • 8.4.1.12 Sequence of work
        • Figure reference tabl
      • 8.4.2 Mechanical extract ventilation systems (MEV)
        • 8.4.2.1 Compliance
        • 8.4.2.2 Provision of information
        • 8.4.2.3 System design
        • 8.4.2.4 Acoustics
        • 8.4.2.5 Building integration
        • 8.4.2.6 Ductwork
        • 8.4.2.7 Fixing and jointing of ductwork
        • 8.4.2.8 Access
        • 8.4.2.9 Electrical installation requirements
        • 8.4.2.10 Handling and storage
        • 8.4.2.11 Commissioning and balancing
        • 8.4.2.12 Sequence of work
        • Figure reference table
    • 8.5 LZC Hot water systems
      • 8.5.1 Solar thermal hot water systems
        • 8.5.1.1 Compliance
        • 8.5.1.2 Provision of information
        • 8.5.1.3 System design
        • 8.5.1.4 Safe discharge
        • 8.5.1.5 Building integration
        • 8.5.1.6 Fixing
        • 8.5.1.7 Access
        • 8.5.1.8 Electrical installation requirements
        • 8.5.1.9 Handling and storage
        • 8.5.1.10 Handover requirements
        • 8.5.1.11 Sequence of work
        • Figure reference table
    • 8.6 Installation and commissioning
      • 8.6.1 Compliance
      • 8.6.2 Installation
      • 8.6.3 Insulation to services
      • 8.6.4 Insulation performance
      • 8.6.5 Testing and commissioning
      • 8.6.6 Handover requirements
      • Figure reference table
  • 9 Finishes
    • 9.1 A consistent approach to finishes
      • 9.1.1 Compliance
      • 9.1.2 External walls
      • 9.1.3 Internal walls and ceilings
      • 9.1.4 Doors and windows
      • 9.1.5 Floors
      • 9.1.6 Glazing
      • 9.1.7 Ceramic, concrete, terrazzo and similar tile finishes
      • 9.1.8 Fitted furniture
      • 9.1.9 Joint sealants
      • 9.1.10 Paint finishes
      • 9.1.11 Sanitary ware
      • 9.1.12 Other surfaces and components
      • 9.1.13 Pitched roof coverings
      • 9.1.14 Garages
      • 9.1.15 External works
      • 9.1.16 Further information
      • Figure reference table
    • 9.2 Wall and ceiling finishes
      • 9.2.1 Compliance
      • 9.2.2 Provision of information
      • 9.2.3 Plastering
      • 9.2.4 Dry lining
      • 9.2.5 Ceramic wall tiling
      • Figure reference table
    • 9.3 Floor finishes
      • 9.3.1 Compliance
      • 9.3.2 Provision of information
      • 9.3.3 Insulation
      • 9.3.4 Screed
      • 9.3.5 Ceramic, concrete, terrazzo and similar tile finishes
      • 9.3.6 Wood finishes
      • 9.3.7 Flexible sheet and flexible tile finishes
      • 9.3.8 Asphalt finishes
      • 9.3.9 Staircase finishes
      • Figure reference table
    • 9.4 Finishes and fitments
      • 9.4.1 Compliance
      • 9.4.2 Provision of information
      • 9.4.3 General provisions – cupboards and fitments
      • 9.4.4 Finishings and internal trim
      • 9.4.5 Joinery
      • 9.4.6 Airing cupboards, cupboards, worktops and fitments
      • 9.4.7 Ironmongery, prefabricated items and other materials
      • 9.4.8 Protection and handover
      • Figure reference table
    • 9.5 Painting and decorating
      • 9.5.1 Compliance
      • 9.5.2 Provision of information
      • 9.5.3 Storage
      • 9.5.4 Conditions for painting and decorating
      • 9.5.5 Timber
      • 9.5.6 Steel
      • 9.5.7 Walls
      • 9.5.8 Wallpapering
      • 9.5.9 Other surfaces
      • 9.5.10 Completed painting and decorating
  • 10 External works
    • 10.1 Garages
      • 10.1.1 Compliance
      • 10.1.2 Provision of information
      • 10.1.3 Garage foundations
      • 10.1.4 Garage floors
      • 10.1.5 Garage walls
      • 10.1.6 Resistance to fire spread
      • 10.1.7 Security
      • 10.1.8 Doors and windows
      • 10.1.9 Garage roofs
      • 10.1.10 Permanent prefabricated garages and carports
      • 10.1.11 Services
      • Figure reference table
    • 10.2 Drives, paths and landscaping
      • 10.2.1 Compliance
      • 10.2.2 Provision of information
      • 10.2.3 Stability
      • 10.2.4 Freestanding walls and retaining structures
      • 10.2.5 Guarding and steps
      • 10.2.6 Drives, paths and landscaping
      • 10.2.7 Materials
      • 10.2.8 Garden areas within 3m of the home
      • 10.2.9 Garden areas
      • 10.2.10 External decking
      • 10.2.11 Landscaping
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10.2 Drives, paths and landscaping

10.2.6 Drives, paths and landscaping

Appropriate access (including private roads, shared private drives, private drives, car parking and paths) shall be provided to and around the home. Issues to be taken into account include:

  1. general construction considerations
  2. drainage
  3. construction details
  4. minimum sub-base thickness
  5. house paths and patios.

Homes should be provided with suitable access through the provision of private roads, shared private drives, private drives, car parking areas and paths, as appropriate.

General construction considerations#

Private roads, shared private drives, private drives, car parking areas and paths should comply with relevant building regulations. Where abutting the home, they should be at least 150mm below the DPC, and laid to falls away from the home (unless a channel or other suitable means of collection and disposal is provided).

All vegetable matter should be removed from the area of the proposed works.

Only suitable fill material comprising clean, well-consolidated crushed rock, hardcore, slag or concrete should be used to make up levels.

Sub-bases should be mechanically consolidated in layers not exceeding 225mm.

Finished ground levels should be compatible with:

  • DPC levels
  • cover levels of drainage access points
  • depth of underground services (gas, electricity, water and drains)
  • adjacent surfaces.

NHBC technical illustration

Private roads, shared private drives and private drives should:

  • be appropriate for the loads
  • provide reasonable access to and from a garage or car parking area
  • have a maximum gradient of 1:6
  • where the gradient is more than 1:10 and the gradient changes, have suitable transition lengths to reduce the risk of vehicles grounding.

Underground drainage or services that are below a private road, shared private drive, private drive, car parking area, path or patio should be protected against damage, as described in Chapter 5.3 ‘Drainage below ground’.

Edge restraint or kerbing should have a profile and foundation, which is suitable to form a permanent supporting edge for the expected vehicle loads on the road or drive.

Pedestrian access should be provided via a path within the curtilage of each home to the main entrance and the secondary entrance where present:

  • where entry to the home can be gained directly from a garage, a path to a secondary access door is not required
  • where the secondary entrance is to a mid-terrace home or ground floor flat, a path to a secondary access door is not required
  • where a garage, carport or car parking area is provided within the curtilage, a path should be provided to it from the home.

Where appropriate, a drive can be regarded as a path for the provision of access.

Paths should have a maximum slope of 1:6. On steeper sloping ground, steps may be required.

Table 1: Suitable path widths

Location and useMinimum width of hard standing (mm)Minimum overall width (mm)
Within curtilage to main entrance, or any entrance designated by Building Regulations900900
Paths used for the removal of refuse to the collection point750900
Paths adjoining a home (with hard standing 100mm or more from the wall of the home)450700
All other cases450600

Drainage#

Private roads, shared private drives and private drives should have adequate rainwater drainage and disposal.

Paved areas should:

  • have vertical alignment, finished levels, transition arrangements and gradients in accordance with the design
  • have surfaces with adequate falls, cross-falls and drainage to ensure that surface water is suitably drained
  • have sub-base levels with the same longitudinal gradient and cross-fall as the finished level
  • have surfaces not flatter than 1:40 or have a camber of 1:40 where no fall is available to avoid ‘flat spots’
  • have surfaces with a minimum finished fall of 1:80 where they form private drives and paths
  • drain away from the home (and garage), or drain to a channel or other suitable means of collection and disposal adjacent to the home
  • not drain surface water from private areas onto adopted areas
  • not be within 2m of a soakaway.

Where paving slabs are laid abutting drainage channels and gully grates, etc the upper surface of the paving slab should be set approximately 5mm above the grating.

Where it is intended to use porous or permeable surfaces as part, or all, of the rainwater drainage system, reference should be made to CIRIA report C753 - The Sustainable drainage system (SuDS) manual.

Construction details#

The construction of private roads, shared private drives, private drives and car parking areas should be constructed in accordance with the tables below and/or other published/approved design procedure.

Table 2a: Private road having frequent use by commercial vehicles

NHBC technical illustration

Table 2b: Shared parking and associated access areas having frequent use by commercial vehicles

NHBC technical illustration

Table 2c: Shared drives having infrequent use by commercial vehicles

NHBC technical illustration

Table 2d: Private drives and parking areas having use by cars and light vehicles

NHBC technical illustration

Notes

1. In the first column, European harmonised names for the pavement layers are with the old UK designations included in brackets.
2. Where a capping layer is specified, sub-base thickness can be reduced. Pavement Design CD 225 Revision 1 gives guidance on capping and sub-base thickness design based on CBR values with and without a capping layer.
3. For the minimum thickness of the sub-base for different CBR values, refer to Table 3.
4. Bond coat in accordance with BS 594987 should be applied to ensure effective bonding of the asphalt layers.
5. Bituminous mixtures/asphalt can be used as a partial replacement of a full thickness granular sub-base type 1 material.
6. If the binder course is subjected to an extensive period of trafficking before the surface course is applied, a recipe mixture containing a higher bitumen content will be more durable/resistant to fretting/ravelling under traffic.
7. Where laid to either a 90 or 45 degree herringbone pattern, the edge perimeter should be laid with one single row of stretcher bond set parallel to the edge restraint. Where block pavers are laid abutting drainage channels, gulley grates, etc the upper surface of the block pavers should be set 3-6mm above the grating. Manufacturer’s declared value markings W3 and S4 are acceptable. Where W3 is 1.0kg/m2 or less and S4 is 45 or more based on ‘C scale unit’ (for abrasion, class A2 = maximum result is 23mm, class A1 = no performance determined).
8. A 38mm thickness of graded 15/20mm unbound aggregate to BS EN 13242 (gravel), well rolled and compacted, should be used.
9. Reference to clauses are in relation to the relevant European and/or British Standards.
10. Asphalt contractors should be certified in accordance with the National Highway Sector Schemes for Quality Management in Highway Works - Scheme 16.

Minimum sub-base thickness#

The thickness of any required capping layer and the sub-base should be determined after investigations and on-site tests have been carried out, with consideration to the:

  • CBR value
  • frost susceptibility of the sub-grade; where susceptible to frost, a suitable capping layer should be included below the sub-base to a suitable depth to ensure that the construction will not be affected by frost heave
  • Granular sub-bases should be tested and certified as being non-frost susceptible and non-plastic.

Table 3: Minimum sub-base thickness for paved areas

NHBC technical illustration

Notes

1. Minimum thickness of sub-base may be considered for reduction when using proprietary geogrid, provided they can be adequately justified and designed by an Engineer in accordance with Technical requirement R5.
2. Specialist advice should be sort to improve the subgrade.

House paths and patios#

The following construction will be generally acceptable for house paths and patios:

  • the sub-base comprising of a 100mm thickness of clean, non-frost susceptible well consolidated crushed rock, hardcore (maximum size 50mm), slag or concrete, the surface of which is blinded with 25mm of sand
  • paving slabs fully bedded in 25mm 1:4 cement/:sand mortar or a suitable alternative.

Concrete paths and patios should be not less than 75mm thick and have a tamped or textured finish. The concrete mix should be suitable to give a durable and frost resistant surface, as described in Chapter 3.1 ‘Concrete and its reinforcement’. Movement joints, not less than 10mm wide, should be provided across the full width of the path at not more than 4m centres. A movement joint is not required at the abutment with a wall unless the opposite edge of the concrete is also restrained.

10.2.5 Guarding and steps 10.2.7 Materials

Last updated: 2nd January 2024

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Technical Disclaimer: The NHBC Standards are produced by NHBC as guidance solely for our builder customers as to how to interpret the technical requirements in relation to the warranty cover provided by NHBC under its Buildmark, Buildmark Choice, Buildmark Link, Buildmark Solo, Buildmark Connect or any similar product from time to time. It has not been created or intended for distribution or use outside of that purpose. The information contained in the NHBC Standards do not constitute advice and is not to be relied upon by any third party. Nothing in the NHBC Standards is intended to, nor should it be taken to, create any legal or contractual relationship. Any third party who chooses to rely upon the information contained in the NHBC Standards shall do so entirely at their own risk and NHBC accepts no duty of care or liability, however caused, in connection with its use or reliance by any third party.