FAQ
Educating Building Owners
Roofing Lingo
Learning industry terms is a great way to equip yourself with the knowledge to be able to read & understand things like Roofing Quotes, Inspections, Warranties, Contracts and Maintenance Plans.
Roofing System Types
Learn the difference between different roofing systems and roof types. A little education goes a long way.
General Commercial Roof Faq
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A roof membrane is a crucial component of a commercial roofing system, serving as a waterproof layer that shields the building from moisture intrusion. It can be made of various materials, including EPDM, TPO, or PVC, and its primary function is to provide a durable, impermeable barrier against rain, snow, and other environmental elements.
Flashing is a critical element in roofing systems that prevents water from infiltrating vulnerable areas like roof penetrations (vents, chimneys, etc.). Typically made of metal or other waterproof materials, it is strategically installed to create a watertight seal around these openings, ensuring a leak-free roof.
Ethylene Propylene Diene Monomer (EPDM) is a synthetic rubber roofing material known for its exceptional durability and resistance to UV rays and weathering. EPDM roofing membranes are commonly used in commercial roofing due to their cost-effectiveness and longevity.
Thermoplastic Olefin (TPO) is a popular single-ply roofing material used for commercial roofs. It is highly reflective, energy-efficient, and known for its ease of installation. TPO roofing membranes are heat-welded to create a waterproof barrier.
Built-Up Roofing (BUR) is a traditional commercial roofing system consisting of multiple layers of roofing felt and bitumen. These layers are alternated and adhered together to create a waterproof and durable roof. Gravel or other ballast material is often used on the surface for added protection.
Polyvinyl Chloride (PVC) is a thermoplastic roofing membrane known for its durability, chemical resistance, and fire-retardant properties. PVC roofs are heat-welded at the seams to ensure a watertight seal, making them a popular choice for commercial applications.
The roof deck is the structural foundation upon which the roofing system is installed. It provides support for the roofing materials and distributes the load evenly across the building’s structure, ensuring the roof’s stability and integrity.
R-value measures the thermal resistance of insulation materials used in commercial roofing systems. A higher R-value indicates better insulation performance, helping to regulate the temperature inside the building and reduce energy consumption.
Roof coatings are protective layers applied to the roof’s surface to enhance its longevity and performance. They can be reflective, helping to reduce energy costs, or elastomeric, providing added waterproofing and flexibility to the roofing system.
Spray Polyurethane Foam (SPF) is a roofing insulation material that is sprayed onto the roof deck. It expands and forms a continuous, seamless layer that provides excellent insulation and acts as an effective air and moisture barrier.
The pitch of a roof refers to its slope or incline. It is typically expressed as a ratio, such as 4:12, indicating how many inches the roof rises vertically for every 12 inches it extends horizontally. Pitch plays a significant role in water drainage and architectural aesthetics.
Roof ballast is a heavy material, such as gravel or pavers, placed on top of roofing membranes to secure them and provide protection against wind uplift. It also helps to control temperature fluctuations and reduce UV exposure.
Eaves are the horizontal overhangs at the edges of a roof. They serve both functional and aesthetic purposes, helping to direct rainwater away from the building’s walls and providing shade and protection from the elements.
Uplift resistance is a measure of a roofing system’s ability to withstand the forces exerted by strong winds. Commercial roofs must be designed and installed with appropriate materials and fastening methods to prevent wind-related damage.
A parapet wall is a low, protective wall built along the edge of a flat or low-slope commercial roof. It serves various purposes, including providing a barrier to prevent falls, concealing rooftop equipment, and enhancing the building’s aesthetics.
Proper roof ventilation is essential for regulating temperature and moisture levels in commercial buildings. It helps prevent condensation, prolongs the life of roofing materials, and ensures a comfortable indoor environment.
A cricket is a sloped structure installed on a commercial roof to divert water around obstacles like chimneys, vents, or skylights. It helps prevent water ponding and ensures efficient water drainage.
The fascia is a trim board that runs along the edge of the roof, providing a finished look and protecting the eaves from water damage. It plays a vital role in maintaining the roof’s integrity and aesthetics.
A mansard roof is a unique architectural design featuring two slopes on each side of the roof. The lower slope is steeper than the upper one, creating a distinctive, often decorative appearance.
A green roof, also known as a living roof, is a sustainable roofing system that incorporates vegetation and plants into its design. It provides insulation, reduces urban heat island effects, and adds aesthetic value.
The soffit is the exposed surface located on the underside of the roof’s overhang. It plays a role in providing ventilation to the attic space and maintaining proper airflow in the roofing system.
An ice dam forms when snow on the roof melts and then refreezes near the eaves. This ice accumulation can block proper drainage, leading to water infiltration and potential roof damage.
A standing seam roof is a type of metal roofing system characterized by vertical seams that are raised above the flat panels. This design provides excellent water shedding and is commonly used in commercial and industrial applications.
Roof underlayment is a protective layer installed beneath the primary roofing materials, such as shingles or tiles. It provides an additional barrier against moisture and helps to improve the roof’s durability and weather resistance.
A drip edge is a metal strip installed along the roof’s edges to direct water away from the fascia and into the gutters, preventing water damage to the roof’s structure and eaves.
A ridge vent is a ventilation system installed along the peak (ridge) of the roof. It allows hot air and moisture to escape from the attic, improving overall ventilation and helping to regulate temperature and humidity.
Gutters are channels installed along the roof’s edges to collect rainwater and channel it away from the building’s foundation. Properly functioning gutters prevent water damage and erosion.
Downspouts are vertical pipes connected to the gutters that carry collected rainwater from the roof to the ground or a drainage system. They play a crucial role in directing water away from the building.
A skylight is a window or transparent panel installed in the roof to allow natural light into the building’s interior. Commercial skylights can enhance energy efficiency and create a brighter, more pleasant workspace.
Single-ply membrane roofing systems consist of a single layer of roofing material, such as EPDM, TPO, or PVC. These membranes are durable, lightweight, and known for their ease of installation.
Roof sheathing is a layer of material, typically plywood or oriented strand board (OSB), installed over the roof deck. It provides a stable surface for attaching roofing materials and insulation.Thermal Expansion
Thermal expansion refers to the tendency of roofing materials to expand when exposed to heat and contract when cooled. Proper allowance for thermal expansion is crucial to prevent damage and maintain the roof’s integrity.
Flashing cement, also known as roof mastic or roof cement, is a sealant used in roofing applications to secure and seal flashings. It provides an additional layer of protection against water infiltration.
Roof penetrations are openings in the roof for vents, pipes, HVAC equipment, or other components. Proper flashing and sealing around these penetrations are essential to prevent leaks.
The dead load is the weight of permanent roof components, including the roof deck, insulation, roofing materials, and structural elements. It is a critical factor in roof design and engineering.
A roof truss is a framework of beams, braces, and other structural members that support the roof deck and distribute its weight evenly to the building’s walls and foundation.
Roof decking is the material installed directly on top of the roof truss or rafters, providing a stable base for the roofing system. Common materials include plywood, OSB, or concrete.
Wind uplift refers to the upward force exerted by strong winds on the roofing system. Roof designs and materials must be chosen to resist these forces and prevent damage or displacement.
A valley is a low-lying area where two roof slopes meet, creating a V-shaped channel for water runoff. Proper installation and flashing are essential to prevent water infiltration in valleys.
The rake edge is the sloping edge of a gable roof, extending from the eaves to the ridge. It serves both structural and aesthetic purposes, enhancing the roof’s appearance and protecting the gable end.
Granules are small, colored mineral particles embedded in asphalt shingles to protect them from UV rays and enhance their durability. They also provide texture and color to the roofing material.
Modified bitumen is a type of roofing material that combines asphalt with modifiers like rubber or plastic. It is known for its flexibility, weather resistance, and ease of installation.
A gable roof is one of the most common roof designs, characterized by two sloping sides that meet at a ridge. It forms a triangular shape and offers effective water shedding.
A roof drain is a plumbing fixture designed to collect and channel water off the roof’s surface. It is connected to the building’s drainage system to prevent water accumulation on the roof.
Tapered insulation is a roofing system that includes sloped insulation boards designed to create a gentle slope for efficient water drainage. It helps prevent ponding water on flat or low-slope roofs.
Cricket flashing, or saddle flashing, is used to divert water around chimneys, skylights, or other roof obstructions. It ensures proper water drainage and prevents water from accumulating behind these structures.
Thermal bridging occurs when heat escapes through roof materials or structural components, leading to energy loss and potential condensation issues. Proper insulation and design can minimize thermal bridging.
Self-adhering roofing membranes are modified bitumen or asphalt-based sheets with an adhesive backing. They are easy to install and provide a secure waterproof barrier when applied to the roof deck.Cool Roof
A cool roof is designed to reflect more sunlight and absorb less heat compared to traditional roofing materials. It helps reduce energy consumption and lower cooling costs by maintaining lower roof temperatures.
Rooftop HVAC units are heating, ventilation, and air conditioning systems installed on commercial roofs. They are commonly used in commercial buildings due to their space-saving design and easy maintenance access.
Epoxy primer is a type of adhesive used in roofing applications to enhance the bond between roof coatings and the substrate. It provides added durability and adhesion.Gable Vent
Gable vents are ventilation openings installed on gable roofs to promote air circulation and release hot air from the attic space. They play a vital role in maintaining proper ventilation and temperature control.
A roof hatch is an access door installed on the roof to allow personnel to enter for maintenance, inspections, or equipment servicing. It typically includes a ladder or stair access system.
The slope ratio expresses the roof’s pitch as a fraction. For example, a roof with a 4:12 slope rises 4 inches vertically for every 12 inches of horizontal run. The slope ratio influences drainage and aesthetic design.
Counterflashing is an additional layer of flashing installed over the base flashing to provide extra protection against moisture infiltration. It is often used in conjunction with step flashing.
Purlins are horizontal beams or structural members installed on the roof trusses to support the roof deck and distribute loads evenly. They strengthen the roof’s structure and help maintain its integrity.
A scupper is an outlet or drainage opening in the parapet wall or roof edge that allows water to flow off the roof. Scuppers are essential for preventing water ponding and ensuring proper drainage.
A roof’s fire rating indicates its ability to resist the spread of flames in the event of a fire. Fire-resistant roofing materials are essential for safety and compliance with building codes.
vapor barrier is a material installed within the roofing assembly to prevent moisture vapor from migrating through the roof system. It helps control condensation and maintain insulation performance.
The roof ridge is the highest point of a sloped roof where two roof slopes meet. It is typically covered with ridge caps or other finishing materials to provide weather protection.
Flashing tape is a specialized adhesive tape used in roofing to seal and reinforce flashings, which are essential for preventing water infiltration at vulnerable areas like roof penetrations and junctions. This tape is designed to provide an extra layer of protection and enhance the waterproofing of these critical points, ensuring the long-term integrity of the roofing system.
An ice and water shield is a crucial component of roofing systems in regions prone to freezing temperatures and snowfall. It is a self-adhesive membrane installed under roofing materials to protect against ice dams and water infiltration. This shield acts as a barrier, preventing melted snow and ice from penetrating the roof and causing damage to the underlying structure.
A roof curb is a raised frame or structure installed on the roof to support rooftop equipment, such as HVAC units, vents, or skylights. Curb installation is essential for keeping the equipment above the roof’s surface, allowing for proper airflow, maintenance access, and protection against water infiltration.
Styrene-Butadiene-Styrene (SBS) is a type of modified bitumen used in commercial roofing. SBS roofing membranes are known for their flexibility and ability to withstand temperature fluctuations. They are commonly used in roofing systems to provide added durability, waterproofing, and resistance to cracking or splitting in extreme weather conditions.
A roof inspection is a comprehensive assessment of the roof’s condition, typically performed by qualified professionals. It involves examining the roofing materials, flashings, drainage systems, and overall structural integrity. Roof inspections help identify potential issues early, allowing for timely repairs or maintenance to extend the roof’s lifespan and prevent costly damage.
A roof walkway is a designated, safe path on the roof surface that allows maintenance personnel to access various parts of the roof without damaging roofing materials. Walkways are often created using specialized materials to distribute weight evenly and protect the roof’s integrity during routine maintenance or inspections.
Solar panel mounting systems are designed to securely install solar panels on commercial roofs. These mounting systems provide the necessary support and angle adjustments for optimal sun exposure, allowing businesses to harness solar energy efficiently and reduce their energy costs.
Bird deterrent measures are used on commercial roofs to prevent birds from nesting or roosting. These measures may include spikes, netting, or visual deterrents. They are essential for protecting the roof and its components from damage caused by bird droppings and debris while maintaining a clean and safe environment.
Hail damage refers to roof damage caused by hailstorms. Hailstones can impact roofing materials, causing dents, cracks, or punctures. This damage can compromise the roof’s waterproofing and structural integrity, leading to leaks if not addressed promptly. Repairs or replacements may be necessary to restore the roof’s functionality.
Ponding water is the accumulation of standing water on a flat or low-slope roof. It can occur due to inadequate drainage or a sagging roof deck. Ponding water can accelerate roof deterioration, potentially leading to leaks and structural damage. Proper drainage systems and roof maintenance are essential to address this issue.
Heat-welded seams are a common method used to join TPO (Thermoplastic Olefin) roofing membranes. During installation, the seams are heated to create a strong, watertight bond between adjacent membrane sheets. This technique ensures the integrity of the roofing system and prevents water infiltration at seams.
Elastomeric coatings are flexible, rubber-like coatings applied to roofing surfaces to provide added protection and waterproofing. They can bridge small cracks and gaps, making them an excellent choice for sealing roof surfaces, extending their lifespan, and enhancing energy efficiency.
A rake overhang refers to the extension of the roof’s edge beyond the exterior wall of the building. It serves both functional and aesthetic purposes, helping to divert water away from the building’s facade and providing a finished appearance to the roof’s perimeter.
A roof scuttle is a roof access hatch or door, typically used for safe and controlled access to the roof surface. It allows authorized personnel to perform maintenance, inspections, or repairs while ensuring compliance with safety regulations and building codes.
Thermal shock occurs when a roof is subjected to sudden and extreme temperature changes. These fluctuations can cause roofing materials to expand and contract rapidly, potentially leading to stress and damage to the roof’s components. Proper insulation and ventilation are essential for minimizing the effects of thermal shock.
Elevation, in the context of a commercial roof, refers to the roof’s height above sea level. Understanding the elevation is crucial for various reasons, including assessing environmental factors, calculating wind load, and complying with local building codes and regulations.
Fall protection measures are critical for the safety of workers on commercial roofs. These measures include guardrails, safety nets, and personal protective equipment (PPE) such as harnesses and lifelines. Fall protection safeguards workers against the risk of falling from elevated surfaces.
Roof tie-off refers to the anchorage and attachment points for safety harnesses and lifelines used by workers on the roof. It ensures that individuals working at heights are securely connected to the structure, preventing falls and ensuring their safety during roofing tasks.
Gutter guards are protective devices installed in gutters to prevent debris, leaves, and other materials from clogging the drainage system. By maintaining clear gutters, these guards help ensure proper water flow and prevent water damage to the building and roof.
A conductor head, also known as a leader head or collector box, is an architectural feature used to collect rainwater from downspouts and direct it into the building’s drainage system. Conductor heads often have decorative designs and serve both functional and aesthetic purposes.Wind rating
Wind rating indicates a roof’s ability to resist wind forces without sustaining damage or detachment. Roofs in different regions are assigned specific wind ratings based on local weather patterns and building code requirements. Choosing the appropriate roofing materials and installation methods is essential to meet wind rating standards.Roof warranty
A roof warranty is a written agreement between the building owner and the roofing manufacturer or contractor. It outlines the coverage for defects, workmanship, and materials, specifying the duration of protection. Roof warranties provide peace of mind to building owners, ensuring that they are covered in case of roofing issues.
Roof load refers to the weight supported by the roof structure, including the roofing materials, equipment, snow, and other environmental factors. Accurate load calculations are essential to ensure the roof’s structural integrity and safety.
Standing water is the accumulation of water on a flat or low-slope roof due to inadequate drainage. It can result from sagging roof decks or clogged drainage systems. Addressing standing water promptly is crucial to prevent roof damage, leaks, and potential structural issues.
Roof pavers are interlocking tiles designed for use on commercial rooftops. They provide a durable and visually appealing surface that can support foot traffic and provide access to rooftop equipment. Roof pavers also contribute to better insulation and stormwater management.
Reroofing is the process of replacing or recovering an existing roof with new roofing materials. It is often done when the existing roof has reached the end of its lifespan or requires significant repairs. Proper reroofing can extend the roof’s longevity and improve its performance.
Cricket construction involves building an elevated, sloped structure on the roof to divert water around obstacles such as chimneys, skylights, or equipment. Crickets help prevent water from pooling and facilitate proper drainage, reducing the risk of leaks and water damage.
Roof sagging refers to the downward deformation or curvature of the roof’s structure, typically caused by excessive weight, inadequate support, or compromised structural integrity. Sagging roofs can lead to water ponding, compromised insulation, and potential safety hazards, requiring immediate attention and repairs.
Roof overburden refers to any additional weight placed on the roof deck, such as equipment, green roofs, or heavy building materials. Understanding the roof’s load-bearing capacity is essential to ensure that the overburden does not exceed safe limits and compromise the roof’s integrity.
Roof edge restraint systems are safety measures designed to protect workers from falling off the roof’s edge. These systems typically include guardrails, parapets, or safety cables, ensuring that individuals working near the roof’s perimeter are secure and protected.