Whether you’re a building owner, surveyor, builder, or simply curious, understanding roofing terminology is key when dealing with repairs, replacements, or new builds.
Here’s an A–Z guide to help you speak the language of roofing.
A is for Asphalt
A material used in roofing, typically as a waterproof membrane. It can be applied as a layer on flat roofs, sometimes called mastic asphalt, or as shingles on sloped roofs.
B is for Battens
Thin strips of wood or metal installed horizontally on a roof to provide fixing points for tiles or slates on pitched roofs.
C is for Counter Flashing
A piece of flashing installed opposite or above base flashing to prevent water penetration behind the base flashing.
D is for Decking
The structural base (often plywood or OSB) attached to the roof’s frame, upon which roofing materials are applied.
E is for Eaves
The edges of the roof that overhang the walls, designed to throw water clear of the walls and foundation.
F is for Fascia
The vertical finishing edge connected to the ends of rafters or trusses; supports the lower edge of the roof and often the gutter.
G is for Gable
The triangular section of wall between the edges of a dual-pitched roof. A common feature in many homes.
H is for Hip Roof
A roof with slopes on all four sides, which meet at the top to form a ridge. It’s more stable and wind-resistant than a gable roof.
I is for Interlocking Tiles
Roofing tiles designed to fit together, providing a secure and weatherproof seal without the need for mortar.
J is for Joist
Horizontal structural members used in framing to support the roof or ceiling loads.
K is for Kick-out Flashing
A small piece of flashing installed where a roof edge meets a wall, designed to redirect water away from the wall and into the gutter.
L is for Lead Flashing
A traditional and durable material used for sealing roof joints to prevent water ingress, especially around chimneys and vents.
M is for Membrane Roofing
A type of roofing system for flat or low-slope roofs, made of synthetic materials like EPDM or TPO, single ply.
N is for Nails (Roofing Nails)
Special nails with large heads and short shanks, used for securing shingles or tiles to the decking.
O is for Overhang
The portion of the roof that extends beyond the exterior walls to protect the siding and foundation from water.
P is for Pitch
The steepness or angle of a roof, typically expressed as a ratio of vertical rise to horizontal run (e.g., 25-degree pitch).
Q is for Quoin (pronounced “koyn”)
Architectural term referring to a corner or the external angle of a building. It can also refer to the stones or bricks used to construct that corner, providing both structural support and aesthetic detail.
R is for Rafter
The sloped structural members extending from the ridge or hip to the eave, supporting the roof deck and its loads.
S is for Soffit
The underside of the roof overhang, usually ventilated to allow airflow into the attic and prevent moisture build-up.
T is for Torch-on Roofing
A type of modified bitumen roof applied using a propane torch to create a watertight seal, commonly used for flat roofs.
U is for Underlayment
A water-resistant or waterproof barrier material installed between the roof deck and top layer of roofing material for added protection.
V is for Valley
The internal angle formed where two sloping roof sections meet. These areas channel a lot of water and require proper flashing.
W is for Wind Uplift
A force that can lift tiles, slates or roofing material off the deck during high winds. Proper installation and materials are key.
X is for XPS (Extruded Polystyrene)
A type of rigid foam insulation sometimes used under roofing systems, especially on flat or low-slope roofs.
Y is for Yield Strength
The amount of pressure a roofing sheet can resist before becoming distorted. It helps determine the durability, weight-bearing capability, and structural integrity of the roofing material.
Z is for Zinc Strips
Installed near the ridge of a roof to help prevent moss, mould, and algae growth, especially in damp climates.
Understanding these roofing terms can empower you to make more informed decisions, whether you’re hiring a contractor, managing a project, or just curious about what’s over your head.
