Energy Efficiency in Traditional Buildings - Dublin City Council

ENERGY EFFICIENCY IN TRADITIONAL BUILDINGS
There is a wide range of quality in available draughtproofing
products and assurances should be sought as
to the lifespan of a product prior to fitting. In addition,
it is important that the product can be removed easily
without causing damage to the historic window frame
to ensure that when it reaches the end of its life it can
be replaced. It should also be noted that flexible
draught-proofing strips such as brushes and rubber
will cease to operate correctly if painted as part of
redecoration works.
As discussed in the section on ventilation above,
windows in rooms with no alternative means of
ventilation such as wall vents or open flues should
never be fully draught proofed.
DRAUGHT PROOFING OF EXTERNAL DOORS
External doors in an older building may have become
ill-fitting over the years and so are often poor at
keeping in heat. Traditional doors can be draught
proofed in the same way as windows with various
draught-proofing strips widely available. The bottom
of external doors can also be fitted with a
weatherboard providing this can be achieved without
damage to a historic door. Letterbox brushes or flaps
can be fitted to reduce draughts. For historically
important buildings, discreet draught proofing should
be used. In some buildings it may be possible to
provide a draught lobby to the interior of the external
doors. For a draught lobby to be successful there must
be adequate space to close the external door prior to
opening the internal door. Installing a draught lobby
in a protected structure may require planning
permission and the architectural conservation officer
in the local authority should be consulted when
considering works.
IMPROVING HEAT TRANSFER
A single sheet of glass will transfer heat quicker than a
double-glazed unit. People feel colder sitting close to
single-glazed windows as they lose heat by radiation to
the cold inner surface of the glass. Tall windows can
result in what is known as ‘cold dumping’, where the
temperature of the air next to window is considerably
colder than the rest of the room, as the cold air is denser
and heavier it falls, or dumps. This is one of the primary
reasons for placing radiators below windows. There are
simple solutions to keeping heat in a room with single
glazing that are more effective than fitting doubleglazed
units and more appropriate for use in a historic
building and several of these are discussed below.
EXISTING SHUTTERS AND CURTAINS
Aluminium draught strips can be seen to all sides of
this door. The metal part of these strips,
unfortunately visible, can be painted (although it is
difficult to achieve successfully) but it is important
that the flexible sealant strip is not
Many Georgian and Victorian buildings were originally
constructed with internal timber shutters to the
windows. During the Edwardian period, shutters
began to fall out of fashion and were supplanted by
heavy curtains. The best way to reduce heat loss in the
evenings and at night is to use such shutters. If they
are no longer operational they should be repaired and
put back in working order. Blinds or heavy curtains,
which could include an insulated inter-lining, when
used with the shutters will further improve heat
retention; there are specially designed thermal blinds
available which can improve on this again. There may
be some scope for upgrading shutters using a thermal
lining applied to the rear of the shutter panels; for the
shutters to continue working it is important that the
overall thickness of the shutter is not increased. The
feasibility of upgrading will depend on the available
depth between the shutter panel and shutter frame.
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