This is one of the most important trades
as it provides both the finishing standard
to the interior of your new home and, where
the outside is rendered, provides the final
weathering coat.
Internally the choice,
for self builders, is whether to opt for hard plaster (a
sand and cement render coat with smooth plaster finish)
or dry lining (a plasterboard finish). In the past this
choice was often dictated by whether the home was built
using traditional masonry construction or was timber
framed. Timber framed
properties can only be dry lined but those using
building traditional masonry construction have the
choice and increasingly, they are opting for dry lining.
1
If you opt for
hard plaster, don't forget to give plenty of
time to dry out naturally before decorating
2
Remember
that bagged plaster has a limited shelf life.
Don't buy or use old plaster.
3
No amount
of paint or wallpapering will cover bad
plastering - choose your contractor with care.
4
Don't
forget that the plasterer will need a foot
scaffold for setting ceilings.
Hard Plaster
Hard plaster requires one, sometimes
two coats of sand and cement render with a finishing
coat of smooth plaster. The sand and cement render can
be replaced by proprietary plasters of differing types,
each one of which is formulated for use a different
substrate. The advantage of hard plaster is that it is
extremely durable. The principal disadvantage is that it
puts enormous amounts of water into the structure and
this can lead to long drying out times.
Dry Lining
Dry lining uses plasterboard fixed to
the walls and is therefore a relatively dry process,
which can be decorated shortly after completion. With a
timber framed home the plasterboard is tacked directly
to the timber studs. When used in traditional masonry
construction, it can either be stuck to the walls by
means of dabs of plaster or tacked to battening, firmly
fixed to the substrate. Dry lining can be taped and
jointed using special paper tape or it can be skim
coated with a thin coat of plaster to provide a surface
finish that is indistinguishable from hard plaster.
The standard plasterboard can be replaced by the more
durable Gypsum Fibre Boards, which provide greater sound
insulation properties and are strong enough to take
fixings directly.
Ceilings
Plastered, or ‘set', ceilings are
jointed with a silk scrim and then finished with a thin
coat of smooth plaster. This is applied by a hand held
trowel and there is therefore the need for a ‘board or
foot scaffold'. Any decorative mouldings or covings are
put up afterwards.