A mixture of bitumen and fine minerals such as clay which is hot-trowelled
onto roofs. The melting point is higher than tar so it has higher
weather resistance. Asphalt occurs naturally in Trinidad bubbling
up in lakes ready mixed with sand, but over extraction has depleted
The boards fixed against the roof covering on a gable roof.
Treated soft wood, measuring around 25x38mm, which is laid horizontally
on top of the sarking felt to hook the tiles / slates on to.
The rounded quadrant shaped tile, which is laid over the hip.
Used on flat roofs to provide weathering and so-called as it is laid
in two or three layers. The felts may be standard bitumen based or
high performance polymer based - the latter has good flexibility properties.
Felts are laid in hot bitumen or have the bitumen factory-applied
to be melted on-site with a flame torch.
The area under the overhanging part of a roof.
A metal sheet cut into brickwork and then dressed over a surface below,
used to deflect water from a joint between two adjacent materials,
such as brickwork and tiles.
The sand / cement fillet around a chimney pot.
The vertical end of a building with a pitched roof where the end wall
goes up to form a triangle.
On a roof which has slopes on all surfaces, i.e. like a pyramid, the
long sloping ridge is called the hip and inside, the rafter is the
Usually constructed from coloured concrete, interlocking tiles have
interlocking edges and hooked tops. The interlocking sides provide
weather resistance without the great overlap of plain tiles, so the
weight over an area is lower. However, the tiles are considerably
heavier than slates, therefore it is very important to check that
the roof structure is strong enough to bear the weight. Interlocking
tiles are much cheaper than plain tiles and are a favourite on lower
cost houses as a replacement for slates. When looking for new property,
be suspicious of older houses that have new interlocking tiles, especially
if similar houses in the area have slates. Visible raised areas of
tiles on the roof, at the point where two homes join, are a sure sign
of overloading of the roof structure. Interlocking tiles work well
at low pitch angles and in exposed areas.
Copper nails used to fix slates will corrode in time, particularly
with the effects of acid rain in city areas. The result is slipping
Clay plain tiles that have wooden pegs to hook over the battens instead
of the hook formed in tile material. These tiles are found on older
buildings and are expensive to replace.
The angle of a roof where two slopes meet the ridge. This is referred
to as a pitched roof but often incorrectly labeled an 'apex roof'.
The traditional tile is termed flat but has a slight round to spot
water creeping up between courses. The size is generally 265x165x10mm
thick and the tiling will be three thick at the maximum overlap. This
provides the best resistance to wind driven rain but makes the covering
heavy compared to slate or interlocking tiles.
Similar in colour and size to plain clay tiles, but at lower cost.
A common interlocking tile made in concrete with two indent lines
and flexible ridges.
This is the waterproof felt lain immediately under the roof tile battens
to keep out wind driven snow and dust. This also acts as a second
The undersurface of any part of a building such as the arch, eaves
or cantilevered section.
When faced with slipping slates through nail sickness, there is no
easy solution as the slate above prevents access to the damaged nails.
In such a situation, it is possible to insert strips of zinc or copper,
bent into long 'S' shaped hooks, to catch the bottom of the slipped
slate. This can then be hooked over the top of the slate above from
underneath. These 'S' shaped hooks are known as tingles.
Where tiles or slates overhang the gable bargeboard, the underside
is bedded in mortar and finished with special tiles, slates or a inert
board, called the undercloaking.
Where two sloping roofs meet, as with two mountains, the valley is
the line between.