• Asphalt Shingle RecyclingReprocessing old and scrap asphalt shingles, mainly by grinding them for use in asphalt road paving.
• Attic CondensationMoisture that condenses on the underside of a roof deck or framing, usually from warm indoor air leaking into a cold attic.
• Basel Green Roof PolicyBasel, Switzerland, has required green roofs on new and renovated flat roofs since a 2002 law change, with rules aimed at biodiversity.
• Blue RoofA flat or low-slope roof designed to store rainwater temporarily and release it slowly, reducing peak flows to storm sewers.
• Building-Integrated PhotovoltaicsPhotovoltaic products that replace conventional building materials in the roof or facade, generating electricity while forming part of the building envelope.
• Bushfire Attack Level (BAL)Australia's rating of a building site's bushfire exposure, from BAL-LOW to BAL-FZ, which sets construction requirements including roofing.
• Class A Fire RatingThe highest fire classification for roof coverings under ASTM E108 and UL 790, for roofs effective against severe external fire exposure.
• Climate Change and RoofingHow a warming climate is expected to change the hazards roofs face, from stronger storms and heavier rain to heat, wildfire and shifting snow.
• Coastal Salt CorrosionAccelerated corrosion of metal roofing, fasteners and flashings caused by salt spray and humidity near the sea.
• Cool Metal RoofingCool metal roofs use reflective, highly emissive finishes that bounce sunlight and shed absorbed heat, lowering roof temperatures and cooling loads.
• Cool RoofA roof with high solar reflectance and high thermal emittance that stays cooler in sunlight, reducing cooling loads and urban heat.
• Copenhagen Green Roof PolicySince 2010, Copenhagen has required green roofs on new buildings with roofs sloped under 30 degrees, as part of climate adaptation.
• Earthquakes and RoofsHow roof weight, attachment and bracing affect building performance in earthquakes, and why heavy tile roofs on weak frames are a known risk.
• Ember-Resistant Roof DetailsRoof vents, gutters, closures and edges designed to keep wind-blown embers from igniting debris or entering the building during a wildfire.
• Embodied Carbon of RoofingThe greenhouse gas emissions from making, transporting, installing, maintaining and disposing of roofing materials, as opposed to operating the building.
• Environmental Product Declaration (EPD)A verified document reporting the life cycle environmental impacts of a product, such as a roofing material, using standard rules.
• FORTIFIED RoofA voluntary US construction standard from IBHS that upgrades roof edges, deck sealing and attachment to reduce hurricane and high-wind damage.
• Freeze-Thaw DamageCracking, spalling and flaking of porous roofing materials caused by water freezing and thawing repeatedly inside pores and cracks.
• French Green Roof and Solar Law (2015)A 2015 French law requiring roofs of new buildings in commercial zones to be partly covered with plants or solar panels.
• Green RoofA roof partly or fully covered with vegetation and growing medium over a waterproofing membrane, used for stormwater, cooling and habitat.
• Green Roofs in GermanyGermany pioneered modern green roof technology and guidelines, and many German cities support green roofs through planning rules and fees.
• Hail Damage to RoofsDamage caused when hailstones strike roofing: bruising and granule loss on shingles, cracked tiles and slates, dented metal and punctured membranes.
• Heat Island Group (Lawrence Berkeley National Laboratory)A research group at Lawrence Berkeley National Laboratory in California that studies cool roofs, cool pavements and urban heat islands.
• Hurricane Roof DamageHow tropical cyclones (hurricanes, typhoons and cyclones) damage roofs, from lost coverings and edges to deck blow-off and wind-driven rain.
• Hurricane TieA metal strap or clip that fastens a rafter or truss to the wall to resist wind uplift; also called a hurricane clip or hurricane strap.
• Ice DamA ridge of ice that forms at the eaves of a snow-covered roof and traps meltwater, which can then back up under the roofing and leak.
• Impact Resistance Rating (UL 2218 and FM 4473)Laboratory classifications (Class 1 to Class 4) that rank roof coverings by resistance to simulated hail impacts.
• Metal Roofing RecyclingRecovery of aluminium, steel, copper and zinc roofing at end of life, and the recycled content used in new metal roofing.
• Rainwater Harvesting from RoofsCollecting rain that falls on a roof for storage and reuse, and how the roof material affects the quality of the collected water.
• Roof Drainage DesignPlanning slopes, gutters, drains, scuppers and overflows so that a roof sheds rain quickly, including during intense storms.
• Roof Insurance and DepreciationHow property insurers value roofs by age and condition, including actual cash value versus replacement cost settlements.
• Roof Insurance DiscountsPremium credits some insurers give for roofs built to resist wind or hail, such as FORTIFIED designations, wind mitigation features and Class 4 coverings.
• Roof Life-Cycle CostThe total cost of owning a roof over a set period, including installation, maintenance, repairs, energy effects, replacement and disposal.
• Roof Lifespan ComparisonTypical service lives of common roofing materials, from asphalt shingles and membranes to tile, slate and metal, and what shortens or extends them.
• Roof Wind Pressure ZonesAreas of a roof (field, edge, corner) assigned different wind design pressures because suction is strongest near edges and corners.
• Roof-to-Wall ConnectionThe joint that fastens rafters or trusses to the top of the walls; a key link in the load path that keeps a roof on in high winds.
• Roofing Fatality StatisticsData showing roofing as one of the deadliest occupations in the United States, with falls causing most deaths.
• Roofing Market Size and StatisticsEstimates of the size and growth of the global roofing materials market, with the dates and limits of the figures.
• Roofing Waste and LandfillWaste generated by roof replacement and construction, its share of construction and demolition debris, and ways to reduce it.
• Roofing WorkforceThe people who install and repair roofs, their numbers, pay and outlook, with US Bureau of Labor Statistics data.
• Rooftop Solar PVPhotovoltaic panels mounted on building roofs to generate electricity, and the roofing issues of load, attachment, waterproofing and roof life.
• Rooftop Solar Water HeaterA roof-mounted solar collector and tank that heats domestic water; Israel made them mandatory on most new buildings in 1980.
• Sealed Roof DeckA roof deck whose panel joints are sealed with tape or a self-adhered membrane so rain cannot pass through if the covering is lost.
• Secondary Water BarrierA layer beneath the roof covering that limits water entry if shingles, tiles or panels are torn off in a storm.
• Shingle Wind Resistance RatingsTest classifications such as ASTM D3161 and ASTM D7158 that indicate how well steep-slope roofing resists wind blow-off.
• Singapore Skyrise GreenerySingapore's policies and incentives that encourage rooftop and vertical greenery on buildings, including the Skyrise Greenery Incentive Scheme.
• Single-Ply Membrane RecyclingCollection and recycling of PVC, TPO and other thermoplastic roofing membranes, including Europe's Roofcollect scheme.
• Snow LoadThe weight of accumulated snow and ice that a roof must be designed to carry, derived from local ground snow data and roof shape.
• Snow Sliding and Snow GuardsThe sudden release of snow and ice from a sloped roof, and the guards and rails installed to break it up and hold it in place.
• Solar ReflectanceThe fraction of incoming sunlight a surface reflects, from 0 (absorbs all) to 1 (reflects all); also called albedo.
• Solar Roof Mounting SystemsRacking that secures solar panels to roofs: penetrating rail systems, seam clamps on metal roofs and ballasted racks on flat roofs.
• Thermal EmittanceHow efficiently a surface releases absorbed heat as infrared radiation, rated from 0 to 1; high values help roofs stay cool.
• Tornado Roof DamageHow tornado winds strip roof coverings, lift decks and remove roof structures, and how the Enhanced Fujita scale uses roof damage to rate tornadoes.
• Toronto Green Roof BylawA 2009 City of Toronto bylaw requiring green roofs on many new large buildings, with coverage that rises with building size.
• Urban Heat IslandThe tendency of cities to be warmer than surrounding rural areas, driven partly by dark roofs and pavement that absorb sunlight.
• UV and Heat Degradation of RoofingHow sunlight and heat break down roofing materials over time through photo-oxidation, embrittlement, chalking and loss of protective surfaces.
• Wildfire RoofingRoof design and materials that reduce the chance of a building igniting from embers, radiant heat or flames during a wildfire or bushfire.
• Wind UpliftThe upward suction and pressure that wind exerts on a roof, which must be resisted by the covering, deck, fasteners and framing.