4. Windows – Treatment will vary
with the window; whether it is
single or double-glazed, sliding
sash or side hung. Check for
draughts, as above, and if the
original windows have been
replaced with double-glazed
units it may be a matter of simply
replacing the rubber seals. Usually
a relatively simple, and cheap,
DIY job. If we have single-glazed
windows, then think about
secondary double glazing. It is
less than a quarter the price of
replacement double glazing and
almost as good.
5. Loft – Put in more insulation than
you might think. At least 300mm
mineral (or sheep) wool and make
sure it is pushed right out over the
top of the walls.
6. Ground Floor – Most pre-1920
houses will have a suspended
timber floor and treatment is as
much to do with draught-proofing
as insulation. If the floor can be
accessed from below, use a semi-
rigid insulation cut slightly wider
than the gap between the joist
and push it in tight against the
underside of the floor boards. Put
in a few tacks to make sure it does
not fall out. If that can’t be done
then a thin insulator, Sempatap or
similar, can be fixed on top. This
is only 8mm thick so it will have
no impact on skirting boards but
doors may need to be trimmed
down.
7. Walls – Insulating the walls will
be the most expensive, and most
difficult task. But 35% of the
heat is likely to escape through
the walls so it is worthwhile
addressing. External insulation
is the best and will genuinely
improve thermal efficiency, but is
not always possible. Equally, thick
internal insulation seldom meets
with unalloyed enthusiasm. An
internet search will find many thin
wall insulation options. These
will work, but mainly by making
the wall feel warmer than any
significant improvement to the
performance of the wall.
73
The one piece of advice you might
want to take is to start at the top of the
list and do as much as you can afford.
Every pound you spend will be repaid
many times over, in reduced bills as
well as in a more comfortable house.
Words by Tim Pullen, eco expert for The
National Homebuilding & Renovating Show
(28-31 March, NEC Birmingham).
Image credits: James Fench, Simon Maxwell
& John Perry