Glossary

RUBBER A material that is capable of recovering from large deformations quickly and forcibly, and can be, or already is, modified to a state in which it is essentially insoluble (but can swell) in boiling solvent such as benzene, methyl ethyl ketone, and ethanol-toluene azeotrope.

SADDLE A small structure that helps to channel surface water to drains. Frequently located in a valley, a saddle is often constructed like a small hip roof, or like a pyramid with a diamond-shaped base. (Also CRICKET.)

SATURATED FELT A felt that that has been immersed in hot asphalt and has absorbed as much asphalt as it can retain under the processing conditions.

SCRIM A woven, non-woven, or knitted fabric, composed of continuous strands of material used for reinforcing or strengthening felts or membranes. Scrim may be incorporated into the membrane by laminating, coating or extruding.

SCUFFING IN The practice of sealing the edges of a bituminous cap sheet by applying foot pressure along the lap.

SCUTTLE A hatch that provides access to the roof from the interior of the building.

SEAM A joint formed by mating together two separate sections of single ply roofing membrane. Seams may be sealed in a variety of ways, including hot-air welding, solvent welding and adhesive bonding.

SEAM STRENGTH The force or stress required to separate or rupture a seam in the membrane material.

SEAM TAPE Cured or uncured synthetic rubber tape used for splicing in lieu of "contact adhesives."

SELF-ADHESIVE MEMBRANE Single ply membrane which can adhere to a substrate and to itself at overlaps without the use of a field-applied adhesive.

SELVAGE A specially defined edge of a material designed for some special purpose such as overlapping or seaming.

SHARK FIN An upward-curled felt sidelap or endlap.SHEAR STRENGTH The stress (pounds [N] or pounds per inch width) required to disrupt a lap seam or bonded joint or attachment by forcing the substrates to slide over each other.

SHINGLE (1) A small unit of prepared roofing designed for installation with similar units in overlapping rows on inclines normally exceeding 25%; (2) To cover with shingles; (3) To apply any sheet material in overlapping rows like shingles.

SINGLE PLY ROOFING A roofing system in which the principal roofing component is a single ply flexible membrane.

SLAG A grayish, porous aggregate left as a residue from blast furnaces and used as surfacing aggregate.

SLIP SHEET Sheet material, such as reinforced kraft paper, polyester scrim, or polyethylene sheeting, placed between two components of a roofing system (such as membrane and insulation) to ensure that no adhesion occurs between them, and to prevent possible damage from chemical incompatibility.

SLOPE The angle of incline of a roof surface as measured in inches per foot (mm/m).

SOFTENING POINT The temperature at which asphalt becomes soft enough to flow as determined by an arbitrary, closely defined test method.

SOLID MOPPING See MOPPING.

SOLVENT CLEANERS Heptane, hexane, white gas, and unleaded gas, used to clean the membrane prior to applying the splicing adhesive in some single ply roofing systems.

SOLVENT WELDING A process used to chemically weld or join together two or more layers of certain membrane materials (usually thermoplastic) by applying a solvent, such as tetra-hydrofuran (THF), to the overlapping surfaces and mating them when the bonding surfaces become tacky. Used most often in welding or sealing seams.

SPLICE See SEAM.

SPLIT A membrane rupture resulting from tensile stress.

SPOT MOPPING See MOPPING.

SPRINKLE MOPPING See MOPPING.

SPUD To remove the roofing aggregate and most of the bituminous top coating by scraping and chipping.

SQUARE A roof area of 100 ft² (9.29 m²), or enough material to cover 100 ft² (9.29 m²) of substrate.

STEEP ASPHALT A roofing asphalt conforming to the requirements of ASTM Specification D 312, Type III.

STRAWBERRY A small bubble or blister in the flood coating of a gravel-surfaced membrane.

STRIP MOPPING See MOPPING.