Timber
1. Check timber floors and skirting boards
with the meter and read the timber scale.
Check the air bricks, size, position (above
ground?) and number.
2. Any readings over 12% are a cause for
concern: above 18% timber is vulnerable to
decay by wood rotting fungi.
3. If necessary take readings through the
carpet and underlay.
4. Jump up and down to assess the stability of
the floor.
5. Look for insect holes – insects prefer damp
timber.
Solid
1. Check solid floors and skirting boards with
the meter and read the timber and masonry
scales. Check the edge of the floors, where
they join the walls. This joint is often damp
due to poor finishing.
2. Any readings over 1.5% in a solid floor
are a cause for concern, there may not
be a waterproof membrane beneath the
concrete or the surface screed or their may
be a water leak.
3. If necessary an overnight test can be
carried out by sticking down a patch of
clear plastic sheeting with insulation tape,
moisture under the plastic sheet the next
day indicates a damp problem.
4. Water leaks are very common in kitchens
and bathrooms and can spread through
concrete and screeds up the walls, giving
rising damp symptoms.
5. Check the outside ground level, which
should be below the inside floor level. The
damp proof course should be a minimum
150mm (6”) above outside ground level.
Summary
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Draw a sketch of the area and walls
▪
Take lots of readings
▪
Note the readings
▪
Look for the pattern
During your tests look for any obvious
causes of damp such as the following;
Internally:
Water leaks from kitchen or
bathroom fixtures or machines.
Externally:
Leaking gutters, downpipes
or drains. Defective pointing or flashing.
High external ground levels relative to or
above the damp proof course. Blocked
air bricks.
If your readings indicate that you have a
serious damp problem that you are unable
to pinpoint and rectify by simple means you
should have your property checked by an
‘expert’ and correct the issue accordingly.
How to test for damp guide
FLOORS
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