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| Flat Roofing In Edmonton |
Flat Roofing In Edmonton is not nearly as common as pitched shingle roofs are. Because of this flat roofs are relatively unknown in Edmonton and the rest of Alberta.
Flat Roofs From Wikipedia:
A
flat roof is a type of covering for a
building. In contrast to the more sloped form of
roof, a flat roof is horizontal or nearly horizontal.
The slope of a roof is properly known as its pitch: Roofs which are
nearly flat are known as low-pitch roofs (as the angle of slope
increases, so the pitch is said to increase).
Any sheet of material used to cover a flat or low-pitched roof is
usually known as a membrane and the primary purpose of these membranes
is to waterproof the roof area. Materials that cover flat roofs
typically allow the
water
to run off from a slight inclination or camber into a gutter system.
Water from some flat roofs such as on garden sheds sometimes flows
freely off the edge of a roof, though gutter systems are of advantage in
keeping both walls and foundations dry. Gutters on smaller roofs often
lead water directly onto the ground, or better, into a specially made
soakaway. Gutters on larger roofs usually lead water into the rainwater
drainage system of any built up area. Occasionally, however, flat roofs
are designed to collect water in a pool, usually for aesthetic purposes,
or for rainwater buffering.
Flat roofs exist all over the world and each area has its own
tradition or preference for materials used. In warmer climes where
rainfall is less and freezing is unlikely to occur, many flat roofs are
simply built of masonry or concrete and this is good at keeping out the
heat of the sun and cheap and easy to build where timber is not readily
available. In areas where the roof could become saturated by rain and
leak, or where water soaked into the brickwork could freeze to ice and
thus lead to 'blowing' (breaking up of the mortar/brickwork/concrete by
the expansion of ice as it forms) these roofs are not suitable.
Traditionally most flat roofs in the western world make use of
tar or more usually tar paper applied over roof decking to keep a building watertight. The tar or
tarpaper is in turn covered in
gravel
to keep the sun's heat, UV rays and weather off it and helps protect it
from cracking or blistering and degradation. Roof decking is usually of
plywood, chipboard or OSB boards (OSB =
Oriented Strand Board, also known as
Sterling board) of around 18mm thickness. The tar coating is applied in one or more coats as a hot liquid, heated in a
tar kettle,
or as sheets of tar impregnated 'paper' glued down and sealed together
at joints by hot tar – once it has cooled, the gravel is spread evenly
over it.
