Dry rot

Dry Rot

Our Dry Rot Service identifies and eradicates fungal decay in timber structures, replaces compromised wood, and applies targeted fungicidal treatments to restore and protect your property’s structural integrity.

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Our fully qualified surveyors are dry rot specialists. They are able to identify the nature, type, extent, cause and source of moisture, while recommending the solution, with a full specification and the cost of the repair.

What is dry rot?

Dry rot is a term used to describe a very specific and unique type of wood rot (Serpula lacrymans). However, despite its common name, it will generally only attack damp timber.

It is the most serious form of timber decay. It is a brown rot that typically occurs on wood embedded in, or in contact with, wet masonry and damp conditions. It is sensitive to heat and light and, therefore, is rarely found on exposed external timbers. It has the ability to transport moisture from damp areas to dry timbers, thus promoting the spread of the outbreak, especially in unventilated areas.

Typically, the timber has deep cracks, both along and across the grain. There is also a distinctive, mushroom smell when dry rot is prevalent.

It is a serious problem across properties in the UK. For an infection to be initiated, there needs to be a spore (or some growth that is already present), oxygen, a suitable temperature, a susceptible food source and water, all of which are to be found in buildings.

How to identify dry rot?

Dry rot is often confused with wet rot, however, there are differences between the two. The biggest difference is the amount of moisture that is needed for both wood rot to germinate.

The characteristics depends on its stage of development. The first evidence of the existence of an outbreak is often the sudden appearance of reddish spores on floors and skirting boards and the presence of a fruiting body (sporophore) or the shrinking/distortion of timbers.

This latter feature can be quite dramatic and sudden; the change from dimensional stability to the instability of the wood visually taking place relatively suddenly.

It flourishes in damp inadequately ventilated conditions, so it will most often be found in enclosed hard-to-reach areas such as under floorboards, behind skirting boards and door frames/casings.

Unlike many other wood destroying fungi, it can readily grow over and through porous masonry and behind plaster, provided that there is a nutritional source (wood) from which it can spread; this ability allows the spread of the fungus from one area to another.

As these areas are often unseen, it is often the case that the wood has already progressed into an advanced state when detected; therefore, it is essential to identify the issue at its earliest opportunity.

  • When exposed to light, the fungus appears to have a lemon, almost yellowish tinge, look to it
  • Dry rot leaves deep cracks running across the grain of the wood, along with evidence of mycelium growth on the wood
  • The affected wood will be brown in colour and will crumble due to a lack of structural integrity, as a result of dry rot using the wood as a food source
  • Ordinarily, the damage is restricted to the wood, however, in some instances, large flat mushroom-like fruiting bodies may also be visible. These can easily grow through decorative finishes such as plaster or paintwork.
  • Dry rot is the much more serious form of rot out of the two, as it can spread over a larger area, compared to wet rot.
  • Another difference between dry rot and wet rot is that wet rot fungus tends to grow on more porous surfaces, for example, wood with a high moisture content of around 50%. Dry rot, however, can grow on surfaces where there is a moisture content of around 20%
Dry rot
Dry rot

What causes dry rot?

Dry rot occurs where the timber is damp and the affecting damp has a moisture content that is in excess of 20%. There are many reasons why the timber in your property can become damp (such as penetrating damp).

The other vital ingredient to causing an outbreak is spores which are omnipresent, meaning they surround us every day, unseen by the human eye.

By themselves, these spores are harmless; however, when the spores come into contact with wet timber, they can germinate, reducing the wood to an unsound structural state.

The fine fungal thread (hypha) digests the cellulose and hemicellulose fraction of woodturning the wood brown and ultimately reducing the timber to a dry and crumbly state. Dry rot does not attack the structural lignin of the wood.

Before any treatment can be made, the damp issues must be solved first. The reason for this is that the treatments will become ineffective if the timber is damp again, resulting in a return of the problem.

Penetrating damp

Caused by external defects such as defective rainwater goods or a leaking roof.

Rising damp

Caused by a possible ineffective damp proof course, for example, where the damp proof course has been bridged.

Condensation

Lack of sufficient ventilation in a property can lead to damp.

Dry rot can affect all types of properties, regardless of their age, as long as there are certain environmental elements allowing it to survive and spread. These elements are a source of food (wood), oxygen, moisture and temperature. In optimal environmental conditions, dry rot can grow up to one metre per month.

It gets its name due to the dry and brittle state it leaves timber after exhausting away the woods nutrients. So for spores to germinate, moisture must be present within the wood above the fibre saturation point. Wood must have a high moisture content in order for infection to commence, therefore, in order to successfully eradicate dry rot, you must initially eliminate the source of moisture.

How dry rot affects your property

Dry rot can affect all kinds of timber from old or new domestic and commercial properties. This form of timber decay is an increasingly widespread concern for homeowners across the UK. If your dry rot problem isn’t treated promptly, then dry rot can become a danger to you and your home.

Sometimes, finding out that there is actually a dry rot problem is the hardest part of the treatment process. Once it has been been identified within the property, help is at hand. RTC will be able to alleviate any stress or concern you may have.

How to treat dry rot?

Dry rot is the more virulent type of wood rotting fungi. Specialist advice is imperative in order to identify the fungus and determine its true extent. From this, recommendations can be made in relation to the extent of the repairs required and the necessary specialist treatments.

To successfully eradicate dry rot, you must initially eliminate the source of moisture. The works will normally involve the replacement of decayed timbers, removal of wall plaster to expose the extent of decay and mycelial growth and the treatment of the wall structure by masonry sterilisation and returning the area to a watertight condition.

For treatment, our and surveyors and technicians will:

  • Locate and eliminate the Source of Moisture.
  • Determine Full Extent of the Outbreak.
  • Remove all signs of strands, mycelium and fruiting bodies.
  • Replace affected Timbers.
  • Increase sub-floor ventilation as required.
  • Promote Drying where possible
  • Sterilise masonry and adjacent timbers using a surface biocide.
  • Apply deep penetrating timber past to timbers as necessary.

Can dry rot be treated effectively?

Dry rot can be successfully treated following a detailed inspection by a professionally qualified surveyor (CSTDB – Certificated Surveyor of Timber and Dampness in Buildings).

Dry rot

The lifecycle of dry rot

Most people don’t understand that dry rot has a life cycle and fights for its own life in extraordinary ways. It needs food to live and to grow, going to extreme lengths to make sure it continues to do so.

The four stages of a lifecycle

Spores

Spores are omnipresent, meaning they exist everywhere. Individually, they are invisible to the human eye, however, when in large numbers, they appear as orange and brown dust; this is one of the simplest ways of identification. The lifecycle of dry rot begins when spores come in contact with timber in a favourable environment. Once on the timber, the spore will germinate and produce hyphae growth.

Hyphae

Hyphae act as the root of the rot, stringing fine strands to grow through the wood and timber. The hyphae will then feed on the sugars within the timber, known as cellulose, hemi-cellulose and lignin. The fungi/fungus produces enzymes to split the sugars, reversing the formation of the wood. These enzymes, however, are unable to break down lignin. The subtraction of these sugars results in cross grain cuboidal cracking, reducing the timber to an unsound structural state. Hyphae then multiply and colonise together, generating mycelium growth, a fluffy cotton-wool like substance.

Mycelium

Mycelium can travel great distances to find new sources of food, and it is this ability to spread through various building materials that allows a dry rot outbreak to progressively feed on timbers throughout an entire property.

Sporophore

Like any life form, dry rot can be stopped by a lack of air, food, or water. But, what makes it unique, is that when short of such vital elements, it produces a self reproduction organ, known as sporophore. This allows the sport bearing surface of the sporophore to shed orange colours spores into the atmosphere in the hope that the spores can land once again in the right environment to carry on germinating and extending the growth period of the dry rot.

Does dry rot spread?

Dry rot is a living growing fungus. As such, it feeds on timbers and will actively seek out new food sources when it has to. If the humidity conditions are right, it can spread rapidly through a property on the hunt for food.

The history of dry rot

Originally known as Merulius Lacrymans, the fungal decay we now know as dry rot, can be dated back to the 18th century. However, the history of its presence in the UK still remains obscure.

Dry rot is thought to have been transported to British shores by ships from Europe carrying infected timbers; in some cases, cargoes were largely destroyed in the ships before they reached the port.

Dry rot survey

If you are having a dry rot survey carried out on your property, you need to be confident that the survey is carried out by experienced, qualified surveyors.

The timber surveyors at RTC will perform a detailed survey of the dry rot affected area before recommending any forms of dry rot treatment. At RTC, our timber surveyors have many years of experience and the relevant timber qualifications, so you can be confident in our diagnosis of your dry rot problem.

You can trust RTC when it comes to diagnosing and formulating a bespoke treatment plan to eradicate this from your property.

How is a dry rot survey carried out?

The surveyor carrying out the survey will:

  • Inspect the causes of the problem; the cause of the outbreak has to be identified to resolve the situation
  • Diagnose the extent of the issue affecting the property
  • Inspect the property to see if there are any further timber issues, such as wet rot
  • Provide detailed information in a written report detailing the correct treatments
  • Provide a complete timber report detailing all the works that need to be carried out on the property to remove the dry rot problem once and for all
dry rot
Dry rot and wet rot

Why have a dry rot survey with RTC?

  • Long-term guarantees as well as the availability of insurance backed guarantees
  • Fully qualified timber surveyors who hold the recognised PCA qualification of CSTDB
  • Speedy response time for surveys and carrying out the work
  • Which? Trusted Trader accredited

What chemicals are used to get rid of dry rot?

For treatment, we use the latest Boron products as Boron compounds are vastly superior for the control of dry rot. The purpose of the chemical surface irrigation is to provide a reliable, protective cordon around the infected area to prevent the reoccurrence of spread of the fungus.

What guarantees do RTC offer?

  • RTC are Property Care Association (PCA) members, therefore, are able to offer the option of a long term insured guarantee for dry rot treatment, issued by QANW.
  • Because the QANW guarantee is genuine insurance, it provides protection if the contractor ceases to trade for any reason. It is also transferable to the new owners if you sell your property. See www.qanw.co.uk for more information.

For any queries, or to book a survey, please get in touch.

Our staff will work closely with you from survey stage, right through to the successful completion of the contract.

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2

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3

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Expert Technicians and Surveyors

4

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Respectful Team Treated Our Home Like Their Own

From initial contact, surveyor visit and 3 days on site undertaking the work we found RTC to be very professional in all aspects. The lads who undertook the work communicated well throughout the job and more importantly treated the property with respect, as if it was their own home. Would recommend RTC without hesitation or reservation.

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Protected Home, Perfect Finish—Excellent Result

Originally recommended by my surveyor after discovering damp in 5 rooms. All the RTC staff were friendly and did a great job in minimising the dust and mess with protected sheeting and flooring throughout the house. The final result is excellent and a big call out to Steve for helping with moving a very heavy radiator and giving me tips on cauking. Highly recommend if you want a fairly priced job by hghly skilled employees and not subcontractors.

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The 2 men that turned up were very polite and the main man Dillon was good at his job got straight on with doing his work everything went as planned and when he had finished was left clean and tidy carpet replaced with new carpet grippers really happy with the work done

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From beginning to end the work was undertaken in a proffesional and efficient manner by skillful and knowledgable people. The workmen arrived when stated and left each day having tidied up and cleaned whereever possible.were. I have no hesitation in recommending RTC.

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Condensation Cleared in Days with PIV System

I recently had a Positive Input Ventilation System fitted in my loft and was very happy with the results. Within just a couple of days the problem with condensation was clearing. Lawrence who fitted the system did a great job and was very clean and tidy also the ladies in the admin department were very pleasant and helpful.

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Outstanding Service by Sam, Stacey, Hayleigh & Mat

I had this company recommended to me and i am so glad they did everyone that ive dealt with from survey sam the girls in the office stacey and hayleigh to the workmen mat and the rest of workforce they did a great job and would use them again reliable tidy really pleased. Thanks again

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Damp Proofing Done Right—Clean, Quick & Reliable

Had RTC in to do damp proof work in dining room and hall way turned up on time everyday kept my property as clean as they could even thought this is a messy job before leaving everyday they made sure all work areas we’re hovered and swept the staff I had at my property were really nice friendly hard working lads they answered all my questions if I ever need them in the future they will be getting a call and can I finish by giving Jack a shout as he was with us though out the works and he is a credit to RTC

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High-Standard Finish That Went Above & Beyond

Fantastic job done, really appreciate the work done. They did more than I expected at a really high standard. Nothing negative I could possibly say so I would recommend to anyone requiring their services. Good job RTC!

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Transparent Pricing & Top-Notch Workmanship

From initial contact with the office, to the visit from the surveyor, the surveyors report which was very thorough as he actually went under the floors, the price for the work and the quality of the job itself was excellent. The surveyor Sam did an excellent job as was the repairs done by Dan and Karl. After the work was completed, I was contacted by the office to check that I was satisfied with work and the quality of the job, which I was. Professional all the way through with good customer service, made to feel I was important to their business. It’s an old adage but big enough to cope and small enough to care fits the bill. Would use again and would have no reservation about recommending them.

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Professional from Damp Report to Final Plaster

Delighted with the service. RTC installed a damp proof course and replastering at my house. The damp survey was professional, detailed and very clear on the work to be done with good accompanying explanations of the issues. The office is easy to contact, answering all my calls and returning them promptly if the person I needed to speak to wasn’t immediately available. The technicians who performed the work were professional and worked fast and hard. They explained clearly all the steps and left the house clean every day. I am really please with the final finish and overall result. They were not the cheapest quote or survey I had, but at all steps were the most professional. Highly recommended.

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I dont write reviews unless there necessary and these guys are, Dale fron RTC was absolutely brilliant very respectful in our home and with our furniture ensuring things were covered up the best he could amazing company.

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From start to finish the company were very professional. Everything was explained to us. Despite the work being very messy, everything was cleaned up at the end of each day. The two lads who completed the work, Wes and George, were hard working, polite and answered my many questions without any problem. The work was done to a very high standard, and it exceeded my expectations. I would highly recommend RTC, I would not hesitate to use them again.