Advice for tenants
If you are in rented accomodation there are many things you can
do to look after the property. This section offers guidance to our
Guidance on keeping your home free from damp and mould
What is condensation?
Condensation in your home is caused by warm, moist air meeting a
cold surface such as glass (windows and mirrors), walls, tiling
etc. When the air cools, it is unable to retain the moisture and
some of it condenses into small droplets of water on these cold
surfaces. You can see this happening on the bathroom mirror when
the room is steamed up from running a bath or a shower.
Modern features such as double glazing and loft insulation are
important to keep your home warm but they can also introduce
problems associated with poor air circulation. Where there is
inadequate ventilation in your home, condensation and stale air may
well result. With the relatively high cost of heating, nobody wants
to keep their windows open when it is cold outside so the
condensation problem has to be reduced as much as possible.
Condensation is very much a seasonal problem occurring during
the colder months – October to April in the UK. During the summer,
the problem is seen to go away. During the winter, ventilation of
your property is usually low (windows and doors closed,
draught-proofing measures in place etc.). This in turn allows the
build-up of water vapour in your property which, in some cases, is
sufficient to cause condensation and the following signs begin to
- Water droplets form on cold impervious surfaces
- Slightly damp wallpaper (often not noticed)
- Development of black mould, frequently in
areas of little air movement such as window reveals, floor/wall and
floor/ceiling junctions, behind furniture up against cold walls and
the well known triangular pattern in top and bottom corners.
- Where the problem is very severe, water will even collect and
remain on double-glazing.
In some cases, condensation may be a long term but intermittent
problem, forming only at certain times of the day or night. In
these cases the only sign of condensation may be mould growth with
the water perhaps evaporating during the day.
You should be aware that the problem can occur well away from
the site of water vapour production. For example, water vapour
produced in the kitchen may diffuse through your property into a
cold bedroom where it will condense on cool walls leading to mould
Steps YOU can take to minimise
1. When cooking:-
a) cover pans with lids
b) avoid leaving kettles on the boil
c) always use the cooker extractor hood fan
d) always use the kitchen extractor fan (if
2. When washing clothes it is always better to dry them outside.
If, however, this is not possible then
a) dry them in the bathroom
b) ensure the bathroom door is closed
c) make sure bathroom extractor fan (if
fitted) is ON
d) ensure the bathroom window is OPEN
If you have a tumble dryer then make sure the vent pipe is run
outside (unless it is the self- condensing type). A simple DIY kit
is available so the vent pipe can be adjusted to run to the
3. It is important to make sure your home is properly
ventilated. There will always be some moisture present in the home
and there should be some form of ventilation available – usually
air bricks on the outer walls and on some inner walls.
UNDER NO CIRCUMSTANCES SHOULD AIR BRICKS BE COVERED OVER.
4. When using the kitchen and bathroom always keep the door
closed whenever possible. This will help to contain the moist or
stale air in that particular room.
5. Where furniture (such as cupboards, wardrobes, chests of
drawers etc) are up against the wall, try to keep a small distance
between the back of the item of furniture and the wall
(particularly if the wall is generally a cold one). Some form of
ventilation in cupboards, wardrobes, chest of drawers etc is a good
idea to keep the air circulating.
6. If moisture droplets have formed on windows and doors they
should be wiped off
7. Whilst it is a good idea to draught-proof your home, it is
important to remember
not to block airways that will prevent air circulation.
A. DO NOT BLOCK FIXED VENTILATORS SUCH
AS AIR BRICKS
B. DO NOT BLOCK CHIMNEYS COMPLETELY
C. DO NOT DRAUGHT-PROOF ROOMS WHERE PROBLEMS
WITH CONDENSATION OR MOULD ALREADY EXIST
D. DO NOT DRAUGHT-PROOF THE KITCHEN OR THE
8. Cold air causes the problems associated with
Particularly in cold weather, you should try to keep your home
warm, with some form of background heating, 24 hours a day, 7 days
a week. This applies, in particular, to bedrooms and especially in
flats and bungalows.