Low Slope Roofing

History in the United States: Composition or what we now know as built-up roofing was introduced in the United States in 1840 utilizing pine tar instead of coal tar or asphalt as the adhesive. Prior to that time low slope or "flat" roofs were waterproofed with metals such as; tin plate, copper, lead and zinc. The use of coal tar bitumen began in 1847 and was followed by a type of asphalt bitumen within a few years. Coal tar and asphalt composition roofs were the dominant systems installed on larger non-residential projects for the next 100 plus years until the invention single ply membranes. One of the earliest single ply roof installations was a neoprene rubber and aluminum system installed on the Ingalls Hockey Arena on the Yale University campus in New Haven, Connecticut. This particular installation, while pioneering, was fraught with problems primarily due to the deterioration of the neoprene in the ultraviolet rays of the sun. Single ply roof systems including; EPDM, TPO, PVC and modified bitumen now have the majority of the market over conventional built-up roofing. The latest industry trends are toward integrated solar, green roofs and vegetative roofs.

Maintenance: Lack of proper maintenance is likely the number one cause of premature roof failure. Time and time again owners have complained that "flat roofs don't work". The fact is they work just fine if properly designed, installed and maintained. A flat roof should be inspected at least once a year by a qualified inspector. Defects should be documented and properly repaired to industry standards. If the roofs are easily accessible then they should be walked twice a year and at that time the drains and gutters should be cleared.

Design and planning: Things to consider when replacing your flat roof; building use and occupancy, location, owner's requirements, deck, building codes, maintainability, warranty, cost, slope, sustainability and future additions. Proper design, installation and maintenance will have a direct impact on life cycle cost.  

Environmental impact: Terms such as; green-tech, sustainability, reflectivity, cool roofing, urban heat island effect and volatile organic compounds are driving major changes in the low slope roofing industry.  A roof system that was once expected to keep the occupants, structure and contents dry can now be expected to save energy, control water run-off, produce electricity, reduce heat emission, provide a recreation area, have a reduced impact on the environment and be aesthetically pleasing.