ROOF
COVERING
Asbestos
Asbestos is made out of mineral fiber and cement. It is available
as flat sheets and corrugated sheets. A flat sheet is 4"
x 4" while a corrugated sheet is 4" x 6" or 4"
x 10" with asbestos, roofs could be made cheaper. However
doctors say that the fibrous element in asbestos is likely to
cause health hazards.
Calicut Tile
This is the most commonly used roofing tile in Sri Lanka. When
used on a roof, a single tile will cover a 1"x 1" roof
area. These are expensive to use than asbestos roof coverings
as a whole.
Half Round Tiles
Half round tile came to use in Sri Lanka in the colonial eras.
If you are using them you have to use few tile layer to perfect
the covering. Therefore this demands a much stronger roof structure
when compared with Calicut tiles. However, half round tiles look
more pleasing.
Covering Tiles
This is a convenient option for half round tiles. First corrugated
sheets of asbestos are laid on the roof structure. Half round
covering tiles are laid on the corrugated sheets thereafter. Therefore;
covering tiles are lighter than the half round tiled roof and
aesthetically pleasing than Calicut tiles.
Cement Tiles
Cement tiles are less expensive than clay tiles. They come in
a vide variety of colors such as green, red, blue etc. However
it is not a good quality product when compared with clay tiles,
as they tend to leak.
Metal Sheets
Metal could be bought from the market in corrugated sheet form.
The most common is a galvanized iron sheet. These are similar
to asbestos in size. But these are glossy in finish.
Corrugated Steel profile sheets are an another form of metal sheets.
They are available in almost any size in many colors. With corrugated
steel profile sheets, the roof angle could be reduced down to
4'.
Transparent Sheets
Transparent sheets could be made out of polycarbonte or Perspex.
These could be used for atriums, out - houses, green houses etc.
