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Dry Rot and Wet Rot

Unfortunately one of the biggest threats to timberwork (apart from woodworm) is fungal decay. Wet rot and dry rot both love the damp and this can cause serious structural damage in you properties.

Dry and wet rot are caused by fungai (Serpula lacrymans) and this can make even the strongest obeams, joists and timbers to collapse into nothing more than a pile of dust. Funnily enough dry rot has to have moisture to survive and thrive and it enjoys living in damp, warm, unventilated conditions. Dry rot can often be located in parts of your property that aren’t easily visible so its not always that easy to dectect until too late. You should also be aware that masonry and plaster can be attacked too, not just timber. It is possible that within a very short space of time the complete structural strength of a building can be compromised.

The most common indicators of dry rot: are-

  • matted whitish growth tinged with yellow and/or lilac patches

  • a growth resembling a pancake with a russet colour at the centre. If you see this you’ll know the fungus has really taken hold. That russet colouration is in fact millions of spores of dry rot – approach with caution!

  • a distinct and quite acrid mushroom-y smell

  • splitting, shrinking or crumbly wood. Try poking timbers with a screwdriver; if it sinks into the wood you’ll know it’s decaying.

How to treat dry rot

Treating dry rot is a two-step process:

Initially we must locate and eliminate the source of the water causing the conditions for dry rot to survive and expand. As with all damp problems we are meticulous in our search for any possible ways for water to enter timber of brickwork, The most common sources are:-

  • leaky plumbing, guttering or pipework including downspouts and overflows from cisterns
  • condensation
  • rainwater coming through gaps in doors and windows
  • damaged or ‘bridged’ DPC (damp proof course)
  • missing roof tiles, flashing or cladding
  • blocked air bricks

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Next page: Woodworm Treatments