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Glossary by Extension Architecture

28 June 2018
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Eugene Kim

our pick

of architectural terms

Decorated letter A for blog on glossary by Extension Architecture

raised panel beneath window, wall tablet or monument

angular meeting point of 2 surfaces

joining elements so they still look unique

large stone block cut with square edges and even faces

court area rising through all levels with roof lights

Axial beam
structural beam resisting lateral loads on its axis

Axial load
load with force distributed along an axis

Decorated letter B for blog on glossary by Extension Architecture

false balcony or rail
in a window

shaft to support handrail

board attached to
roof gables

Bar-stayed girder
with bars at each end to assist with weight or tension bearing

Batement lights
windows with vertical sides but the lower line is not horizontal

Bending load
shear force which deflects and bends
the beam. The elasticity of a
material is determined by dividing stress by strain

Bi-fold doors
sliding doors which fold together (like an accordion) to maximize opening

Oval place-holding pieces used in

decorative brick-
laying technique such as herringbone, Flemish, basket

carved projecting stone

rough block set for subsequent carving
overhanging wall support
Brise soleil
canopy or projection to shade window
from excess sun

Decorated letter C for blog on glossary by Extension Architecture Cantilever
small projecting platform for aesthetic effect
Cavity wall
air cavity between parallel masonry surfaces
low pedestal for support or presentation
flow of movement of users in a building
Clear float glass
controlled cooling, perfect parallel to avoid distorted vision or reflection
structural weight-bearing post which negates the need for a wall
metal casing for surface-mounted cables or pipes
the covering or cap of a wall
like a small flying buttress out of a wall to carry an extra weight
upper decorative plastering
Countersinking screws
where they can be screwed down flush or below surface
roof ridge ornamenting
wood shrinking and warping
small dome
Cyrto style
circular portico
Decorated letter D for blog on glossary by Extension Architecture Deck
bridge surface
structural element that transmits lateral loads to the vertical resisting elements of a shear wall
cuboid projecting from roof slope to add headroom and windows
Double depth plan
structural layout of 2 room depth but lacking a central aisle
Dry wall
eliminates wet skim

Decorated letter E for blog on glossary by Extension Architecture Eaves
where the roof projects proud of the wall line
raised dias or platform (from French language)

Decorated letter F for blog on glossary by Extension Architecture Façade
frontal exterior plane of a building
semi-circular radial window
piece of wood on rafter ends to attach gutters
First fix
wiring, pipes, pre-finish
Floating floor
sound-proofing technique using fibre to alternate conductive materials
Floating furniture
supported narrowing of base for visual enhancement
Floating wall
column-fixed partitions which are open at the top, bottom or both
work which does not protrude from a plane
Flying rib
exposed structural beam
Flying stairs
wall-mounted treads with open risers
mini-foundation for wall
ground area within the perimeter of a structure
recess on surface of brick

Decorated letter G for blog on glossary by Extension Architecture Gable
triangular top apex of an end wall encased by 2 roof slopes
2 sided roof with split angles. The upper being shallow and the lower steep. It used to be known as a Dutch roof and was used on American barns

Decorated letter H for blog on glossary by Extension Architecture Hip roof
where all sides slope down from the ridge line
section connecting host building to wing or annex portions

Decorated letter I for blog on glossary by Extension Architecture i-beam
another name for RSJ (rolled steel joist), or steel beam

Decorated letter J for blog on glossary by Extension Architecture Jettying
where the area of the upper floor is greater than the footprint or ground floor

Decorated letter K for blog on glossary by Extension Architecture Keystone
central stone at the zenith (top) of an arch, securing the other stones

Decorated letter L for blog on glossary by Extension Architecture Laminated beam
plastic skin sandwiched with 2 sheets for safety in the event of breakage
Laminated glass
engineered beam which is stronger and more aesthetic than timber beam
the ‘gap’ in a window allowing daylight into the interior
Lightning rod
damage and fire preventor via conduction of electricity from light storms, from the roof to the ground
shaft with rooflight to illuminate basement or unlit section of building
to support weight above a window
Load-bearing wall
Active structural wall in a building, bearing weight above
half-moon shaped area

Decorated letter M for blog on glossary by Extension Architecture Mansard roof
Mansard roof = like the gamrel but with 4 sides (not 2) with split angles. The upper being shallow and the lower steep. Used by French architect Mansart in C17
character face for decoration, like gargoyle
repeat pattern for linear border
1. damp-proof skin 2. mechanical properties of shells with negligible movement
Metal studwork
threading wires or pipes into prefab. holes
strip of beading as part of finish
window division or divider
Decorated letter N for blog on glossary by Extension Architecture Newel
support column for spiral staircase
Normal stress
from a vector force which is perpendicular to the cross section

Decorated letter O for blog on glossary by Extension Architecture Onion dome
onion-shaped dome
series of mouldings

Decorated letter P for blog on glossary by Extension Architecture Parapet
roof level wall for disguise or safety
additional building for leisure
framed area above a window
support structure for dome
Piano nobile
columned building surrounding fountain
the main floor in large Renaissance house
bridge support
Pillar boutant
stone or chain support
column partly protruding proud of wall surface
Plate girder
reinforced girder with steel perpendicular plates attached at either end via bolts, rivets or welding
Plate glass
high quality glass
pedestal to display statue or support a structure
portico to shelter visitors outside entrance
porch with columns
work which protrudes above or proud of a plane
Decorated letter Q for blog on glossary by Extension Architecture Quadriporticus
quadrangle colonnade portico
corner stone

Decorated letter R for blog on glossary by Extension Architecture Rake
A rake is an eave or cornice running along the roof gable. It is sometimes called a raking or sloping cornice.
A cornice return when a horizontal roof-cornice meets a gable rake. You get Greek returns or the soffit, boxed or box soffit returns.
Ridge board / beam
A ridge board sits above the ridge beam and props up the rafters. It sits on top of the ridge beam which transfers the roof load to posts and end walls.
open or solid height between stair treads
Rods in axial loads
cylindrical, enclosed tube
circular hall or room, sometimes topped with a dome
rolled steel joist or steel beam
Decorated letter S for blog on glossary by Extension Architecture Sash
enclosure to frame window casing
Second fix
connect water, gas, electric. Apply finishes. Install sockets, fittings, sanitaryware
Shear load
stress from vector force parallel to the cross section
Shear wall
wall structure with counter panels against lateral load
Sheet glass
thin glass
lightweight convex structure for modern-style roofing
board concealing rafters to form ceiling
short stairs to platform entrance to flats
piston-like parts which resist longitudinal compression or tension
Stud wall / stud partition
non-loadbearing wall
Summer beam
central weight-bearing beam that supports joists and sits on posts rather than a wall
art nouveau radial decorative feature
electricity source current
Suspended ceiling
set on lower joists to create a larger space for safer accommodation of pipes, wiring and ducts with regards to fire risk

Decorated letter T for blog on glossary by Extension Architecture Ties and tie rods
linear, structural tension-resisting component
Timber framing
heavy timber construction with pegged joints
circular force
(window) light on top of door and encased by doorframe
one step on a staircase
triangular structural element connected to fortify roof or bridge
Truss bridge
roof bridge with triangular units
Decorated letter U for blog on glossary by Extension Architecture Undercroft
brick-lined storage cellar

Decorated letter V for blog on glossary by Extension Architecture Veneer
cost-saving technique of fine wood skin, backed with cheaper base
Ventilation shaft
vertical space allowing a storey building to be ventilated
distant view through a window
Decorated letter W for blog on glossary by Extension Architecture Weep hole
for drainage from cavity wall
appended section of a building, like the short arms of a cross

Decorated letter X for blog on glossary by Extension Architecture Xyst
covered portico promenade; columned walkway

Decorated letter Y for blog on glossary by Extension Architecture Y connection
a three-part electrical junction

Decorated letter Z for blog on glossary by Extension Architecture Ziggurat
pyramid-shaped tower
chevron pattern in tiles, wood flooring or bricklaying



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Eugene Kim

Eugene Kim, Founder and Managing Director of Extension Architecture, has led the firm for over 14 years, consistently delivering quality solutions. His dedication has been key to the company's growth and success.

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