Commercial roofing terms

A–C

Asphalt Shingles

Common residential roofing material made from fiberglass and asphalt, known for affordability and ease of installation.

Ballast

Loose stone or gravel placed on top of a roof membrane to hold it in place, protect it from UV exposure, and provide weight against wind uplift.

Base Sheet

The first layer of a built-up or modified bitumen roofing system installed over insulation or deck to provide a smooth, stable surface for subsequent layers.

Built-Up Roofing (BUR)

A traditional commercial system made by alternating layers of bitumen (asphalt or coal tar) and reinforcing fabrics (plies), topped with gravel or a reflective coating.

Cap Sheet

The top layer of a modified bitumen or built-up roof system, often with granules or reflective surfacing.

Cant Strip

An angled strip used where the roof deck meets vertical walls or curbs to create a smooth transition, improving membrane adhesion and reducing stress.

Commercial Roof Coating

Protective liquid membrane applied to existing roofs to extend their lifespan and improve waterproofing.

Commercial Roof Maintenance

Ongoing inspections, repairs, and preventative care to extend the life of a commercial roof system.

Commercial Roof Repair

Fixing leaks, damage, or wear on commercial roofing systems to restore functionality.

Commercial Roof Replacement

Removing and installing a new commercial roof when the existing system is beyond repair or expired.

Commercial Roof Restoration

The process of repairing and recoating an existing roof system to extend its life, improve waterproofing, and enhance energy efficiency without full replacement.

Coatings (Roof Coatings)

Liquid-applied membranes used to extend roof life and improve energy efficiency. Common types include acrylic, silicone, polyurethane, elastomeric, and asphalt-based coatings.

Cool Roof

A reflective roofing system designed to reflect more sunlight and absorb less heat, lowering building cooling costs.

Cover Board

A rigid board installed between the insulation and membrane to improve durability and fire resistance.

Crickets (or Saddles)

Small peaked structures built into flat roof systems to divert water toward drains and away from HVAC curbs or skylights.

D–F

Elastomeric barrier

A flexible, waterproof coating typically used in construction to seal and protect surfaces such as roofs, walls, or foundations. It’s made from elastomeric polymers, which allow it to stretch and return to its original shape without cracking.

EPDM

A durable synthetic rubber roofing membrane used in low-slope commercial buildings. Known for its flexibility, weather resistance, and long service life.

Flat Roofs

Low-slope roofing systems commonly used in commercial settings. These roofs often require specialized materials and drainage solutions to prevent water buildup.

G-I

J-L

M-P

Mechanically Attached

A membrane attachment method using screws and plates to fasten the roof system to the deck.

Metal Edge

A flashing component installed at roof perimeters to protect the membrane and provide a clean finish.

Metal Roof Restoration

The process of repairing and renewing an existing metal roof to extend its lifespan and improve its appearance and performance.

Modified Bitumen

A rolled asphalt-based membrane reinforced with polyester or fiberglass, often installed using heat, adhesives, or cold-applied methods.

NDL (No Dollar Limit) Warranty

A commercial roofing warranty that covers the full cost of repair or replacement, regardless of cost, if the system fails within the coverage terms. Usually offered by manufacturers on high-end systems.

Overburden

Any material or structure (e.g., solar panels, pavers, rooftop gardens) installed on top of a roofing system.

Penetration

Any object that passes through the roof deck or membrane, such as vents, pipes, or skylights, requiring flashing to prevent leaks.

Polyurethane Coating

A durable liquid-applied roof coating known for high tensile strength, flexibility, and chemical resistance.

Q-S

Reflective Coating

Reflective coating is a roofing treatment designed to reflect sunlight and reduce heat absorption. Commonly applied to commercial roofs, it helps improve energy efficiency and extend roof lifespan.

Roof Coating

A protective layer applied over existing roofs to restore waterproofing and reflectivity, extending service life.

Roof Repair

The process of addressing leaks, damage, or deterioration in roofing systems to maintain performance and integrity.

Roof Replacement

Complete removal and reinstallation of the roofing system when repairs are insufficient or the system has failed.

Roof Maintenance

Routine inspections and repairs designed to prolong roof life and prevent costly damage or failures.

SPF (Spray Polyurethane Foam)

A closed-cell foam sprayed onto roofs that expands and hardens, creating a seamless, insulating waterproof layer.

Scupper

An outlet in the side of a building’s parapet wall that allows rainwater to drain from a flat roof.

Silicone Coating

A UV-stable and waterproof liquid coating used to restore and protect flat roofs, especially in ponding areas.

T-Z

TPO Coating

A thermoplastic polyolefin-based coating applied to restore aged TPO membranes, improving reflectivity and waterproofing.

Urethane Coating

A tough, flexible liquid-applied coating known for excellent chemical and abrasion resistance, commonly used in commercial roof restoration.

Vapor Barrier

A layer installed to prevent moisture from passing from the interior of a building into the roofing system.

Walk Pads

Protective mats installed on commercial roofs to provide safe access for maintenance and prevent membrane damage from foot traffic.