Glossary of Building Terminology
Acadamies Capital Maintenance Fund (ACMF)
A projecting structure, or wing, which is part of the original building rather than a subsequent extension.
A perforated brick built into a wall for providing ventilation. Used, for instance, to ventilate the underside of timber ground floors, blocked fireplaces or a roof space.
Is the prevention of tying or binding. Anti ligature devices are used to prevent vulnerable people from accidentally or intentionally self harming, (typically hanging).
Anti Ligature Device
A device intended to provide a specific function but from which it is not possible for a ligature to remain secured when subjected to loads representative of a person intended to inflict self harm or to manipulate a security device.
A curved structure built to distribute weight over an opening in a wall.
An architect is a person trained and licensed to plan, design, and oversee the construction of buildings. To 'practice architecture' means to provide services in connection with the design and construction of buildings and the space within the site surrounding the buildings, that have as their principal purpose human occupancy or use.
A moulding around a doorway or window opening. It usually covers the joints between the frame and the wall finish, thus hiding any shrinkage gaps which may occur.
The sharp external edge where where two surfaces meet at a point.
Material used in the past for insulation and fire protection. Can be a health hazard. Specialist advice should be sought if asbestos is found.
Cement mixed with up to 15% asbestos fibre as reinforcement. Typically used in roofing, rainwater goods, fire-proof linings and various other claddings and linings. It is fragile and will not usually bear heavy weights. Hazardous fibres may be released if cut or drilled.
Black, tar-like substance, designed to be impervious to moisture. Used on flat roofs and floors.
AutoCAD is a software application for both 2D and 3D computer-aided design (CAD) and drafting.
The narrower part of a building, or wing, which extends rearwards beyond the “main“ structure, being an original feature rather than a subsequent extension. This is sometimes called an “outrigger“ in different parts of the country.
The lining and flashing arrangement at the back of a chimney stack (on the upslope side) to divert rainwater away from the stack.
Timber, sometimes decorative, placed along the verge of a roof at a gable end.
A “room sealed flue“, normally serving gas appliances, which allows air to be drawn to the appliance from outside whilst also allowing fumes to escape.
A post or vertical pillar supporting a handrail or parapet rail.
A row of balusters, or other infilling, below a handrail on a landing, stair or parapet.
Thin strips of timber, commonly used to support roof tiles or slates.
Thickening out of render, in a curved shape, to form a drip to deflect water. Usually found at the base of a wall, above the damp-proof course.
Shaped concrete slope beside drainage channel within an inspection chamber. Also known as "haunching".
A length of wood used to provide cross bracing to a set of roof trusses. Also describes the roof member spanning across ceiling joists to provide improved support.
A joint or notch cut into a timber (typically a rafter) where it connects with another timber.
Black, sticky substance, similar to asphalt. Used in sealants, mineral felts and damp-proof courses.
The regular arrangements of bricks, blocks or stones in a wall so that the units may be joined together. The principal types of bond used in domestic construction are English, Flemish, header, stretcher, rat-trap, diagonal or garden wall bond.
Diagonal support in a timber door.
The arrangement of timbers spanning across roof trusses to provide lateral stability.
A lintel, often timber, over an opening such as a fireplace or bay.
Building surveyors work in most real estate markets including residential, commercial, retail, industrial, leisure, education and health. Consequently there are a wide variety of opportunities for building surveyors to work in both the commercial, private, and public sectors. Many building surveyors work for property consultancies, public sector organisations, real estate owning clients and contractors as well as in a number of specialist niche areas such as insurance, rights to light, party wall matters etc. As well as strong technical skills, building surveyors need to have strong people skills and the highest levels of integrity. Clients, whether a large corporation or an individual member of the public, need to have the utmost confidence in the impartial advice given by building surveyors
A brick or stone support to a wall designed to resist lateral movement.
The lead bars in leaded light windows.
The weather-proof finish formed with tiles, or stone or concrete copings, over a wall, parapet or chimney.
A window composed of hinged, pivoted or fixed sashes.
A moisture barrier inserted above a window or door opening to deflect moisture that transfers across the outer leaf of brickwork back to the outer face rather than letting it cross the cavity at lintel level causing dampness internally. In many cases, the lintel itself acts as a cavity tray though this arrangement is not always appropriate.
Traditional modern method of building external walls of houses comprising two leaves of brick or blockwork usually separated by a gap ("cavity") of about 50mm (2")
Cement Fillet A weatherproofing joint between roof slopes and abutting brickwork such as walls or chimneys.
The Construction, Design and Maintenance Regulations 2007.
The Construction, Design and Maintenance co-ordinator.
A simple method of drainage comprising a watertight holding tank, which needs frequent emptying. Not to be confused with "septic tank".
To cut into plaster, brickwork etc. to receive cables and pipes.
Often referred to as "particleboard". Chips of wood compressed and glued into sheet form. Cheap method of decking to flat roofs, floors and (with Formica or melamine surface) furniture and kitchen units.
A horizontal tie beam of a roof, which is joined to opposing rafters at a level above that of the wall plates, designed to restrain opposing roof slopes. Absence, removal or weakening can lead to roof spread.
A central heating boiler that also provides hot water “instantaneously“ on demand, usually within a pressurised system. With this form of boiler there is no need for water storage tanks, hot water cylinders etc.
Usually stone or concrete laid on top of a wall as a decorative finish and designed to stop rainwater soaking into the wall.
Projection of stone, brick, timber or metal jutting out from a wall to support a weight above.
A moulding at the junction between a wall and ceiling. Can also include a moulding at the top of an outside wall designed to project and throw raindrops clear of the wall.
Curved junction between wall and ceiling ie. a type of cornice.
A terminal to a flue pipe to aid discharge of gases and exclude the weather.
Projecting course of tiles to a wall or chimney to prevent rain from running down the face of the brickwork.
Pairs of curved timbers in period buildings which run from ground level and meet at the ridge.
A dome or lantern shaped feature built on top of a roof.
This term is defined as work that is required to be carried out on an agreed cycle and can be annually or every number of years. Gas servicing is annually while close window and fence painting can be every 5 or 6 years. Other work includes Electrical safety checks (every 5 years), common light bulb renewal and drainage checks.
The bottom one metre or so of wall clad with timber, originally designed to provide protection to the wall, and also covering the area most likely to be affected by rising damp. The top edge is finished with a Dado Rail.
Layer of impervious material (bitumen felt, PVC, slate etc) incorporated into a wall and designed to prevent dampness rising up the wall, and lateral dampness penetrating around windows, doors etc. Various alternative methods are available for damp-proofing existing walls including "electro-osmosis" and chemical injection.
Horizontal layer of impervious material (usually polythene or bitumen) incorporated into floors or slabs.
The Disclosure and Barring Service (DBS) enables organisations in the public, private and voluntary sectors to make safer recruitment decisions by identifying candidates who may be unsuitable for certain work, especially that involve children or vulnerable adults, and provides wider access to criminal record information through its disclosure service in England and Wales.
Deathwatch Beetle (Xestobium rufovillosum)
Extremely serious insect pest that attacks structural timbers. Usually affects old hardwoods with fungal decay already present.
Responsible for carrying out Section 11 Landlord & Tenant Act 1985 expert witness reports (EWR's) single and joint inspections, producing cavity wall defect reports, insurance defect diagnosis reports and schedules of reinstatement.
A construction with a window that projects from a sloping roof.
Dry Rot (Serpula lacrymans)
A very serious form of fungus that attacks structural and joinery timbers, often with devastating results. Flourishes in moist, unventilated areas, but the spores can survive in dry conditions.
The lower edge of a roof.
Powdery white salts crystallised on the surface of a wall as a result of moisture evaporation.
Particularly strong and dense type of brick, often used as a damp proof course in older buildings.
Brickwork with alternating courses of headers and stretchers.
Expert Witness Report prepared usually under Section 11 of the Landlord & Tenant Act 1985 also sometimes referred to as the Disrepair Surveyor.
A board fixed to the rafter ends along the roof eaves.
Cheap, lightweight board material of little strength, used in ceilings or as insulation to attics. Considered to be a fire risk.
A thin strip of wood, cement, slate etc. used to fill a narrow joint.
A side wall.
A sheet cover formed over a joint, such as between a roof covering and a chimney or wall, to render it waterproof. Normally formed in metal (lead, zinc, copper) or cement.
A mortar weathering on the top of a chimney stack surrounding the base of the chimney pots to throw off the rain and thus prevent it from saturating the stack.
Brickwork with alternating headers and stretchers in each course.
A smoke duct in a chimney, or a proprietary pipe serving a heat producing appliance such as a central heating boiler.
See 'thermal imaging camera (TIC)' for explanation.
Older, usually shallow, form or foundation of brick or stone.
Normally concrete, laid underground as a structural base to a wall. In older buildings these may be brick or stone.
A pair of sashes the height of a door and hinged to serve as a door and window.
In building terms, the handles, knobs, locks etc. fitted to doors and windows.
Upper section of a wall, usually triangular in shape, at each end of a ridged roof.
Used for filling the joints between wall and floor tiles.
An opening into which rain and waste water are collected before entering the drain.
A channel along the eaves of a roof or the edge of a path for the removal of rainwater.
Broken bricks or stone which, consolidated, are used as a base under floors and patios.
A brick laid end on.
Swelling of clay sub-soil due to the presence of moisture. Can cause an upward movement of floors or foundations in extreme cases.
The sloping angle where two roof planes meet to form a ridge.
A saddle shaped, angular or half round tile fitting over the junction of the roof slopes at a hip.
An open funnel or hopper shaped head at the top of a rain or waste pipe to collect rainwater and/or waste from one or more pipes.
Health and Safety Executive.
The ability to absorb moisture from the atmosphere.
Describing work done in the place where it is finally required, e.g. concrete may be pre-cast off site in sections which are later taken to the position where they are required, or it may be cast 'in situ' on the site itself.
Commonly called a manhole. An access point to a drain comprising a chamber (of brick, concrete or plastic) with the drainage channel at its base and a removable cover at ground level.
Tiles which lock together to form a watertight roof with only minimal lapping.
The lowest part of a drain.
Vertical side of a doorway or window.
The mortar bedding between bricks or stones.
A timber or steel beam directly supporting a floor or ceiling.
The roughness of a surface which provides a bond for any application of paint, plaster, render, tiles etc, or spaces between laths or wire meshes which provide a grip for plaster.
A liquid applied to knots in softwood prior to painting to prevent them showing through at a later date.
Land surveying is the technique, profession, and science of accurately determining the terrestrial or three-dimensional position of points and the distances and angles between them, commonly practiced by licensed surveyors, and members of various building professions. These points are usually on the surface of the Earth, and they are often used to establish land maps and boundaries for ownership, locations (building corners, surface location of subsurface features) or other governmentally required or civil law purposes (property sales).
Downhill movement of unstable earth, clay, rock etc often following prolonged heavy rain or coastal erosion, but sometimes due to sub-soil having inherently poor cohesion.
A roof light constructed like a lantern with fixed and/or opening glazing.
The overlap of slates, tiles and other coverings.
Any base for plasterwork; typically thin wooden strips or expanded metal.
A structure, the sloping roof of which abuts a higher wall.
A method of door construction whereby the vertical boards are fixed together with horizontal members (ledges). The strongest design will be ledged, braced and framed but all combinations are found.
A device by which means can be used to inflict harm by restricting normal breathing and/or blood flow and/or a flexible device which can be attached to a security device in order to enable its manipulation.
The wood finish to a window or door jamb.
A horizontal beam over a door or window opening usually carrying the load of the wall above. Often lintels can be partially or completely hidden from view.
Slats laid at an angle incorporated into a door or window. Can be hinged to allow ventilation/light.
Longhorn Beetle (Hylotrupes Bajulus)
A serious insect pest mainly confined to the south-east of England, which can totally destroy the structural strength of wood.
Liquid Petroleum Gas or Propane. Available to serve gas appliances in areas without mains gas. Requires a storage tank.
A roof made with slopes of different pitches, usually providing an upper floor of useable space within a roof structure.
A generic term for any sealant used in the building process.
A board that has a groove cut into one edge and a tongue cut into the other so they fit tightly together (we use this term to describe a type of door found in some period buildings).
Medium density fibreboard.
A floor between the ground and first floors, often accessed off a half landing.
A hand held device used by Surveyors to identify moisture levels in building/s and or building material/s with a green/yellow/red scale and or digital moisture percentage read out display. The latest meters can detect moisture under tiled floors and in walls using non- invasive radio frequency waves.
Mixture of sand, cement (or lime), and water used to join stones, blocks or bricks, and for pointing and general filling.
Vertical bar dividing individual lights in a window.
Post supporting a staircase handrail at top and bottom. Also, the central pillar of a winding spiral staircase.
A specific shape where a concave arc flows into a convex arc. An ogee gutter has particular profile, is usually formed in cast iron, and is still very common in Victorian housing.
A projecting structure, normally a window.
A projecting course of brickwork, either a feature of the construction, or resulting from structural movement.
The finish to the ground surface beneath suspended floors.
A curved roof tile which hooks over adjoining tiles, typical in some 1930 s construction.
Low wall along the edge of a roof or balcony, or extending over the roof slopes above a party or gable wall.
A gutter behind a parapet usually provided with a flexible metal or other impervious lining.
Plaster finish to the inside of a chimney flue.
The wall which separates, but is shared by, adjoining properties.
A low pitched gable.
A vertical column of brickwork or other material, used to strengthen the wall or to support a weight.
The angle of slope to a roof.
Sandwich of plaster between paper. Commonly used for ceilings and partition walls.
The projecting base of a wall.
Board made from veneers of wood glued with the grain laid at right angles.
Outer edge of mortar joint between bricks, stones etc.
See 'moisture meter' for explanation.
Horizontal beam in a roof providing intermediate support to the rafters.
Unplasticized polyvinyl chloride. Used in window frames and replacement eaves.
A quantity surveyor (QS) is a professional working within the construction industry concerned with construction costs and contracts.
The external angle of a building, or bricks or stone blocks forming that angle.
The distortion, or tendency to distort, laterally as in changing a rectangle to a non-rectangular parallelogram.
A sloping roof beam, usually timber, forming the carcass of a roof.
A horizontal part of a door frame or window.
An additional arch over a lintel.
Smooth or rough cast cement or lime based covering to a wall, either internally or externally, sometimes with pebbledash or other textured finish.
A wall built to hold back a bank of soil.
The side or top faces of a window or door opening.
The highest part or apex of a roof where two slopes meet.
A specially shaped angular or half round tile for covering and making weather-tight the ridge of a roof.
The vertical part of a step or stair.
Moisture soaking up a wall from the ground by capillary action.
Rolled Steel Joist.
A rough render finish to external walls.
Felt used as an underlining to a roof.
The frame of a window that holds the glass.
Final smooth finish of a solid floor; usually cement or concrete.
Private drainage installation whereby sewage is collected into a chamber and decomposes through the action of bacteria, with remaining solids requiring removal periodically, and liquids running off to a water course or soakaway.
Downward movement resulting from failure of the components of the building, normally the foundations. All properties settle to some extent, and this can show as cracking and/or distortion in walls. Very often minor settlement is not of great significance to the building as a whole.
A large, underground pipe or drain used for conveying waste water and sewage. The Local Authority is usually responsible for the sewers, which collect the effluent from various drains, the drains being the responsibility of the land owners.
A naturally occurring crack in timber. Shakes can appear quite dramatic, but strength is not always impaired.
Horizontal external boarding, usually timber or PVCu.
Small rectangular tiles of wood (often cedar) used on roofs instead of tiles, slates etc. Sometimes also used to face walls.
The raked (angled) part of a ceiling sometimes found at the perimeter of a top floor room, being the plastered underside of the principal roof rafters. This occurs where the ceilings are set at a level higher than the tops of the external walls.
A window set into a roof slope.
A pit, filled with broken stones etc., below ground to take drainage from rainwater pipes or land drains and allow it to disperse.
Piece of flexible metal fitted to interlock with slates or tiles and make a watertight joint between a wall and a roof or at a hip or valley. Flashings are used over the soakers at a joint against a wall or chimney.
The underside of an arch, beam, staircase, eaves or other feature of a building.
A vertical pipe that conveys sewage to the drains. Its upper end it usually vented above the eaves.
A horizontal course of bricks set on end over a window or door opening.
Splitting of masonry, tiles, concrete etc., usually due to the freezing and expansion of trapped water (frost damage).
A valve on a gas or water supply pipe which is used to cut off the supply.
The end piece of a gutter.
Lightweight wall construction comprising a framework of timber faced with plaster, plasterboard or other finish.
A brick or block laid lengthways.
The sloping board to which the steps of a staircase are attached.
A course of brickwork that projects beyond the face of an external wall.
A support, usually to a purlin.
Downward movement resulting from failure in the ground.
Soil lying immediately below the topsoil.
Thermal Imaging Camera
A thermal imaging camera (colloquially known as a TIC) is a type of thermographic camera used in firefighting. By rendering infrared radiation as visible light, such cameras allow firefighters to see areas of heat through smoke, darkness, or heat-permeable barriers. In addition, these devices are now commonly used to detect cold/hot spots in torch on flat roof applications, loft and cavity wall insulation and an also be used to diagnose types of condensation in building/s.
Metal bar passing through a wall, or walls, in an attempt to brace a structure suffering from structural instability, normally lateral.
Strips of lead or other metal used to hold slipped slates in position.
Mortar applied on the underside of roof tiles or slates to help prevent moisture penetration. Not necessary when a roof is underlined with felt.
Horizontal bar of wood or stone across a window or top of door.
The horizontal part of a step or stair.
Cut joist where an opening is formed in a ceiling, roof or floor, for example a roof hatch or stairwell.
A prefabricated triangular framework of timbers used in most modern roof constructions.
A lining of felt, PVC, or similar, laid over the rafters and beneath the tiles and battens, to provide a second line of defence to a roof against weather penetration.
Method of strengthening weak foundations whereby a new, stronger foundation is placed beneath the original.
Horizontal or sloping channel, usually lead or tile lined, at the internal intersection between two roof slopes.
The edge of the roof, especially over a gable, or around a dormer window or skylight.
Timber normally fixed on top of a wall to receive floor joists or roof rafters.
Usually a piece of metal bedded into the inner and outer leaves of a cavity wall to provide a physical connection between the two.
A pipe from a wash hand basin, sink or bath to carry away the waste water into the drains.
A board fixed externally to the bottom of a door to exclude driving rain.
Wet Rot (Coniophora puteana et al.)
Decay of timber due to damp conditions. Not to be confused with the more serious dry rot.
A small drain hole or gap in brickwork formed to allow the escape of water.
Colloquial term for beetle infestation, usually intended to mean Common Furniture Beetle (Anobium punctatum), by far the most frequently encountered insect attack in structural and joinery timbers. The wood is attacked by the larvae of the beetle.