Most self builders will use the same plumber for the
central heating as they use for the domestic hot water
but there are separate heating engineers. If separate
tradesmen or companies are used then it is important
that they liaise with each other and with the electrician.
A heating engineer should be able to take your
plans and design the most effective system for your home,
taking into account wall thicknesses, insulation values, room
sizes and window and door openings.
Key Points
1
Consider your lifestyle before
deciding on the best heating system for your new home.
2
If you opt for underfloor central heating don't forget
to advise your designer which flooring medium you'll
be using. Carpets
and underlay are not as efficient at transmitting heat
as tiles.
3
A heated towel rail on a separate circuit with individual
time controls is an inexpensive added feature for the
bathroom.
4
Consider putting a radiator or towel rail in the linen
or airing cupboard. Modern cylinders with thermal lagging
do not give off much heat.
5
Always use a plumber who
is familiar with the systems you have chosen. Do not become
the teacher.
The most commonly used and perhaps most cost effective
and efficient system for hot water and central heating is
the combination of a boiler and radiators. The efficiency
of this partnership is greatly increased by the use of thermostatically
controlled radiator valves (TRV's). These allow each room
to be set at the required temperature and react to changes
in temperature caused by sunshine or other extraneous factors.
Underfloor Heating
Underfloor central heating is increasingly popular with
self builders and there are several companies that specialise
in these systems. However, in general they all come down to
a series of pipe loops set within the floor zone and controlled
by room thermostats. Whilst radiator systems work at fairly
high temperatures (65 / 80 degrees), underfloor systems work
at relatively lower temperatures (45 / 55 degrees). This suits
the condensing type boilers, which are at their most efficient
at the lower temperatures.
It is more expensive to install and it may be more expensive
to run but with the increasing popularity of tiled or wooden
floors and the fact that it provides a consistent background
heat with few cold spots, it is the choice of many. With a
relatively slow response time, it is not best suited to those
whose occupation of
the home is limited to a few hours a day as it is at its most
efficient when run on an almost continuous basis, perhaps
with a night time set back temperature a few degrees lower
than the daytime settings. Intelligent controls can increase
the efficiency by anticipating and reacting to changes in
the external temperature and translating that to the home's
requirement for warmth.
Underfloor central heating works most efficiently within
a screeded or solid floor rather than a suspended timber type.
A good compromise, therefore, in cost and efficiency terms
is the use of underfloor central heating to the ground or
solid floors
with radiators fitted with TRV's to the upper or suspended
timber floors.
Mention should also be made of electric underfloor heating
systems, which have relatively low installation costs and
can be run at around 1p per hour per square metre. These can
be used in combination with radiator heating systems to provide
warmth to otherwise cold tiled floors.