Dry and Wet Rot Treatments

Timber Decay, Timber, Timber Replacement, Timber Repair, Dry Rot, Wet Rot, Timber Treatment

Although both Wet and Dry require similar conditions to begin, both requiring timber as a source of nutrients and high moisture, their characteristics, potential damage and treatments differ. Generally, the treatment of an outbreak for either will also require additional works to ensure the effective treatment of the outbreak and aid in the prevention of a future outbreak. 


Regardless of what type of rot you suspect you have it is important to identify the outbreak at the earliest opportunity to limit the damage caused and minimise the spread of the outbreak. 


Inspections for either type of Rot will generally involve some form of intrusive works such as lifting floor boards etc. to fully detail the outbreak and minimise any additional works that may be unexpected. 


Dry Rot


Dry Rot is more severe than a Wet Rot outbreak due to its destructive nature and the fact that it can actively move from one area to the next, even through brickwork etc. seeking out fresh timber to continue the outbreak. Dry Rot attacks timbers, removing the nutrients from them for its food source before seeking new timber. Timbers that have been attacked lose structural strength and become weak.


For an outbreak to occur moisture is required and in the inspection and treatment of Dry Rot it is essential that the source of moisture is identified, stopped and prevented from re-occurring for the future safeguarding of a property from a repeat outbreak.  


Key Identifying Factors Include: 


1- Damaged Timber - Often will crumble easily in your hand with cuboidal sections. Generally timber will look weak and brown in colour. 


2 - Mycelium - Appears when Dry Rot is spreading and to the eye looks like candy floss / cotton wool in appearance , colour can vary from white to grey. 


3 - Concentrated Spores - Should an outbreak be occurring yet unnoticed a further identifying feature can be patches of orange / rust coloured spores on floor surfaces etc. 


4 - "Cob-Webbing" On Timber - Created by the spores of dry rot, these strands could be mistaken for cobwebs especially in areas where access isn't regular e.g. disused cellars or sub-floor voids. These help the Dry Rot outbreak spread.


5 - Fruiting Bodies - Appear once an outbreak is established and the current food source cannot sustain the outbreak and the Dry Rot will release spores to start a new cycle. Visually they are generally "pancake" in shape and thickness with an orange / brown coloured centre containing the spores and white outer rim. 


6 - Smell - An outbreak generally causes a damp, musky smell that will be constantly noticeable within a property. 


As destructive as on outbreak can be, Dry Rot can be treated and your property restored. The most important thing is identifying an outbreak as early as possible.


Dry Rot Inspection  


Due to the ability to seek new areas for the outbreak then a Dry Rot inspection will generally involve multiple areas of a property being inspected and where required floorboards, skirting boards or wall finishes removed and disturbed. Whilst this may seem a heavy handed approach to an inspection it is vital to understand the severity and scale of an outbreak so an efficient and effective plan of works can be detailed.


Generally, the more information that can be gained from an inspection the more accurate the specification, quotation and programme for the works can be within reason, ensuring there are as few unexpected additional works and delays as possible.


Dry Rot Treatment 


Treatment of Dry Rot will include the removal of decayed timbers with re-installation being undertaken in new pre-treated timber. Identification and elimination of the moisture source. Depending on the severity of the outbreak it may also be necessary to remove contaminated wall plaster and skirting boards, again which would be re-installed new. Following this areas will be treated with various biocides including sprays and gels to ensure the outbreak has been stopped and help futureproof against outbreaks. 


On-going maintenance maybe required such as drying out works and a monitoring schedule is highly advised post works. 


Wet Rot 


Unlike Dry Rot, Wet Rot is generally confined to the general area of an outbreak and requires a regular source of moisture. This could be very high levels of condensation in an area, defective guttering or plumbing or rainwater ingress into the property. Whilst destructive in its own right, Wet Rot is generally less destructive than Dry Rot.


Key Identifying Features Of Wet Rot:


1 - Damaged / Weakened Timber - Timber affected by Wet Rot will often be soft and spongy and depending on the outbreak look slimy in appearance. Affected timber will also appear to be darker in colour than that of unaffected surrounding timber. 


2 - Smell - Due to the high moisture content of areas where a Wet Rot outbreak has occurred there will generally be a smell that is damp and musky. 


3 - Growths - Depending on the type of outbreak and severity will depend on the type of fruiting body / growth. Generally growths are strand like and can even look like fine roots. Colours of the strands vary on the type of outbreak but can be white or grey. 


4 - Shrinkage - When the timber dries out due to a change in conditions the timber itself often becomes susceptible to shrinkage and cracking. When dry the timber will also easily crumble into small / fine particles.


Wet Rot Inspection


An inspection will generally require some form of invasive inspection such as removing floorboards due to the main body of an outbreak often occurring in places such as sub-floor voids and unused cellars etc. As per a Dry Rot inspection whilst this may seem heavy handed and cause unneeded disruption it is essential to diagnose the outbreak and scale of the works required. 


Wet Rot Treatment 


Treatment of Wet Rot will include the removal of affected timber and installation of new. Chemical treatment will then be undertaken to the surrounding area. 


Ventilation will also be installed within the area and where possible this will be natural to stop issues of cracking etc. of timber when drying out which can be caused when drying out is rapid. e.g. through mechanical ventilation or heat. 


It is also paramount to identify the source of the moisture and eliminate it.