Dry Rot Repairs


Dry Rot Repairs

What is Dry Rot?

Dry Rot is a fungal timber decay occurring in poorly ventilated conditions in buildings, which can cause severe structural damage to buildings by weakening the timber strength in floorboards and joists.

Despite its name, Dry Rot fungi Serpula lacrymans thrives in timber as a result of elevated moisture levels.  Unprotected timbers are at risk of an attack by fungal decay when the moisture content of the timber reaches 28–30%. Once established, the fungi can remain active in timber with a moisture content of more than 20%. It is therefore vital to find the source of the moisture and rectify this as quickly as possible prior to carrying out Dry Rot repairs.

Dry Rot Lifecycle

The life cycle of Dry Rot can be broken down into four stages:

Once the dry rot fungus has gained a foothold it will break down the wood fibres and render the wood weak and brittle.

What to look out for

Faulty roof coverings, defective rainwater goods, deteriorating masonry and plumbing leaks are all common causes for elevated moisture levels within a building.

A Dry rot outbreak results in the decomposition of wood and appears as cracking and powdering of the wood – known as cuboidal cracking.

Other signs to look out for:

  • Wood shrinking, darkening, and cracking in a ‘cuboidal’ manner (see photo)
  • White, fluffy cottonwool like mycelium develops under humid conditions.
  • Strands develop in the mycelium; these are brittle and when dry and crack when bent.
  • Fruiting bodies forming.  Fruiting bodies are a soft, fleshy pancake like fungus or bracket with an orange-ochre surface. The surface has wide pores.
  • Rust red coloured spore dust frequently found close to fruiting bodies.
  • Active decay produces a musty, damp odour.

Treatment of Dry Rot

An outbreak of dry rot in a building can be extremely serious as it is hard to eradicate and requires drastic remedies to correct. Significant decay can cause the strength and structure of timbers to be put in jeopardy, leading to instability which can eventually cause the structure to collapse if left untreated.

Dry rot can be very difficult to eradicate unless all the decayed wood is removed, and spores are killed off.

Put simply, Dry Rot remedial repairs are a 3-step process:

Step 1 – Find and fix the source of the moisture.

Step 2 – Remove damaged, degraded wood and replace with new.

Step 3 – Apply a borate wood preservative to all timbers to prevent further growth of Dry Rot fungus reforming and kill off any fungus already in the wood.

Hampton’s Fungal Decay treatments are covered by our 10-year guarantee.