| Despite
its name, dry rot is anything but dry. With a very grand
Latin name of Serpula lacrymans, it is the cause of major
decay in buildings causing extensive damage. Described as
a brown rot, it most often occurs in damp timber which is
in contact with, or embedded in, wet brickwork or masonry.
The fungus is very sensitive to temperatures of over 25
degrees centigrade especially in drying conditions.
Exposed timbers and timbers where there is good
ventilation are rarely affected.
Damaged
timber takes on a very dull brown colour, mostly
developing deep cracks along and across the grain. The
timber loses weight as it loses moisture and will crumble
between the fingers. Unlike some wet rots, there is no
hardened surface to disguise this drying out as the whole
section of timber is affected.
The
dry rot is a fungus, developing a fruit body at the source
of its damp home. The fruit body is normally found on
timber attached or at least in contact with masonry, where
damp conditions can prevail. The body is quite tough and
fleshy to feel, and develops a pancake like shape. The
centre is a yellow ochre when it is young and this
develops to a deep rust colour when it is allowed to grow.
The deepening in colour is a result of the fine, brown
spores it produces which are generally gathered in a dust
below the body. The edges of the fruit body will be white
or grey...This fruit body may be the first sign of dry
rot.
Named
"dry rot" because of its apparent ability to
grow in dry areas, this clever fungus has developed the
ability to soak up moisture from timber, totally drying it
out, and then develop strands which can travel across and
through bricks and mortar to other timbers in unventilated
conditions. It cannot feed on the masonry but carries the
moisture with it in the strands to allow it to spread. |
