Dry Rot

Is Dry Rot a big deal?

Many things can affect the structure of your home, but few are as terrifying as the dreaded dry rot. Once this fungal growth begins to affect your home, you will find that you have a serious problem. You may have heard about this issue before, but how much do you know about it? As a property owner, it is your duty to educate yourself well on this matter. That way, you can eradicate the issue before it even starts.

Your home is most likely one of your greatest investments. To protect your investment, it is important to be able to spot small problems before they become major expenses. Dry rot is one of those problems.

Dry rot is caused by a fungus that feeds on wood and weakens it. Wood becomes cracked and brittle and eventually breaks down. Dry rot is particularly a problem in older homes where wood may not have been treated to prevent rot damage.

Dry rot is a serious problem that can affect anybody. If you are looking to either buy or sell a property that has dry rot, then it should be treated as soon as possible to minimise structural damage to the property.

To help guide you through how to handle a dry rot problem, this helpful guide explains the seriousness of dry rot along with some tips on creating a dry rot problem. It also explains:

  • What is dry rot, and how is it caused?
  • Identifying the signs that you may have dry rot
  • How can dry rot affect the buying and selling process?
  • Steps to take to treat and prevent dry rot

At Hitch Property Constructions, we offer timber repairs work from simple timber repair to almost new structures, renovations, and extensions.

What is dry rot, and how is it caused?

Dry rot, otherwise known as ‘Serpula Lacrymans’, is a destructive wood-rotting fungus that despite its name, attacks damp timber. The optimum temperature for dry rot to grow is at 22ºC with the maximum temperature being 26 ºC.

Dry rot is very destructive because of its ability to spread on to all sorts of materials ranging from carpets to living room furniture. One of the root causes of dry rot is dampness. Several types of dampness can cause dry rot, but one of the main causes is penetrating damp. This can be as a result of heavy rainfall penetrating the property or because of damaged rainwater goods.

Dry Rot

The signs that you may have dry rot in your property

Dry rot is quite distinctive compared to other rots and has several key characteristics.

  • Mycelium growth. This type of growth is a white/grey cotton wool like substance and is normally present on the timber.
  • The smell is also a key indicator that you have dry rot appearing in your property. This wood-rotting fungus has a distinctive damp, musty odour which gets stronger as the dry rot spreads.
  • The damaged timber will appear to be dried out, and the wood will be broken up through cuboidal cracking. The wood also tends to darken as the dry rot attack worsens.

There is often confusion surrounding the differences between wet rot and dry rot as there are similarities between them both. This can often leave property owners feeling confused as to the nature of their problem. An inspection from a dry rot specialist must be made as soon as possible to correctly identify the outbreak as well as put together an action plan to treat the affected area.

The main difference between wet and dry rot is that wet rot occurs more regularly than dry rot and is less serious as it doesn’t spread and usually only attacks one timber. Wet rot needs a high moisture content of around 50 per cent for the rot fungus to be present while dry rot only requires moisture of 20 per cent. If wet rot is left untreated, then it can cause structural problems to your property due to the timbers weakening from sustained dampness.

What does dry rot look like

Identifying dry rot at an early stage is vital to minimising the amount of damage it can cause to your property and reducing the eventual repair bill. While our guide below will help you to understand and recognise what dry rot looks like, you should be aware that it is likely to be found in areas of the property where people do not often look such as under floorboards, behind plasterboard or up in attics.

One of the early signs of dry rot is a musty, unpleasant smell. If this sounds familiar, it might be worthwhile having a snoop around your home for any of the signs listed below:

  • Damaged Timber: Timber affected by dry rot will often darken in in colour and will become so dry and brittle it will break or crumble easily. Timber affected by dry rot will also have distinct “cuboidal cracking.”
  • Concentrated Spore Dust – Dry rot spores are very common and usually harmless. However, if dry rot spores start to appear in concentrated patches of rust coloured dust, this is a sure sign of an active dry rot problem.
  • Hyphae: Dry rot spores begin to produce hyphae when they come into contact with timber in damp and humid conditions. Hyphae are white/grey strands that look similar to spider silk.
  • Mycelium: Mycelium is a grey/white cotton-wool-like mass that dry rot produces when it spreads from timber it can no longer feed on. If you identify dry rot mycelium, it is vital that you treat the problem there and then as it is likely to get a lot worse.
  • Mushroom Style Fruiting Bodies – The last stage in the dry rot lifecycle is the most visually striking – the fruiting body. These fleshy masses look like large rust-coloured mushrooms, and they grow when dry rot needs to pump fresh spores into the air to find more timber.

To help you identify dry rot, we have a dedicated page of dry rot images you may want to browse. At the same time, if you recognise any of the signs or symptoms either above or on the pictures page then, we would recommend that you should consult our specialist team to determine if you require a course of dry rot treatment.

What impact does it have?

So, what is the big deal about this type of rot? Well, if you don’t treat the situation fast, you could be jeopardising your property. The growth can cause structural problems for your home. If you ignore the issue for a long period, you might find that this fungus destroys the structure of your house. In the long term, that could lead to the home caving in on itself. Of course, this terrible fate only happens in difficult situations, but why take the risk? If you don’t do something about the rot, you could find that you need to pay thousands and thousands to repair it. The structure of your home may become weak and unstable.

How does dry rot affect the buying and selling process?

Having a dry rot problem with a house you are selling, or buying could prove to be a big headache. Dry rot can cause serious damage to the structural integrity of your building by feeding on the timbers. The property could therefore be made structurally unstable if the timber is infected with dry rot, resulting in giving any potential buyer a reason to pull out of the house sale.

Check out our range of timber repairs Melbourne at Hitch Property Constructions. 

Steps to take to treat and prevent dry rot from taking over your home

If you are looking to sell your property, and you suspect you may have a dry rot problem then treating dry rot in your property should be carried out by a dry rot specialist to prevent further damage occurring, as well as ensuring that the correct type of rectification takes place.

The most important part of treating dry rot is to identify the source of the damp issue as this is the main source of food for the dry rot to grow. There can be steps that can be undertaken by the property owner to reduce the risk of dry rot, such as installing underfloor ventilation. This will remove the stale, moist air from the property and as a result, reduce the risk of a dry rot outbreak.

Fixing any external defects your property may have will also help keep the risk of dry rot at bay. In a majority of cases, this can be carried out by the homeowner. Things such as removing blockages from drainage pipes can help reduce the risk of penetrating dampness affecting your home. To prevent a dry rot outbreak from occurring again, you will need a specialist dry rot contractor to specify and apply treatments to your property correctly.

If you are unsure of how to deal with a dry rot outbreak and you need the dry rot problem treated effectively, then it is always best to contact a qualified dry rot surveyor. Having a thorough survey carried out can ensure that you will receive expert advice on the best way to deal with your dry rot problem and ensure that the issue will not occur again.

The Dry Rot Life Cycle

Mycelium Growth

Mycelium growth will appear as white or grey cotton wool-like substance. Mycelium can spread extensively across numerous building materials in search of a new source of food – in this case, wood.

The fruiting body (Sporophore)

The fruiting body or sporophore is easily identifiable with its ‘pizza-like’ appearance. These fruiting bodies can appear in an array of shapes and sizes dependant on the conditions present. Most of these round-shaped fruiting bodies are a rusty deep red colour (the spores) with the outer parts of this growth being a much lighter white colour. The spore dust from these fruiting bodies can be the first indication to a property owner that dry rot is present, and a fruiting body is lurking somewhere nearby.

Affected Wood

As dry rot’s sole purpose is to dry out and remove moisture from the wood, a good indicator of a dry rot issue in the affected wood itself. This will look dried out and will have, therefore shrunk as a result. This wood will most likely be brittle and warped, and the grain of the wood will have cuboidal shaped cracking features.

Dry Rot Smell

The most common symptom of dry rot, even without physically seeing the outbreak, is the presence of a damp, musty and fungal smell. The smell may not necessarily mean there is a dry rot issue, but would certainly indicate an issue with dampness; however, dampness can often lead to dry rot depending on the extent of the issue.

What are the Differences between Wet Rot and Dry Rot?

We are often asked by customers: “What is the difference between wet rot and dry rot?” We can tell you that there are major differences between these two very different types of wood rot.

Identifying Wet Rot

  • The wood is more often than not going to feel soft and spongy – a clear indication of structural damage to the wood.
  • Typically a black fungus appears on the infected wood.
  • Any paint finish on the timber will become damaged. However, in some instances, the paintwork can look perfect on the exterior but may well be rotting underneath the paint.
  • If the decay is in an advanced stage, it will have dried out the wood. This then means that the wood will crack and crumble easily.

Identifying Dry Rot

  • 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 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, a 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.
  • The difference between dry rot and wet rot is that the wet rot fungus tends to grow on more porous surfaces, for example, wood with a high moisture content of around 50%. Dry rot, however, tends to grow on surfaces where there is moisture of around 20%. If left untreated wet rot will almost certainly cause major structural issues as a result of structurally weakened timbers.

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. New sources of food been fresh timbers. If the humidity conditions are right, dry rot can spread rapidly through a property on the hunt for food.

How to Deal With Dry Rot

Dry rot should be treated as soon as possible to avoid severe damage occurring. If you do suspect dry rot might be causing damage to timbers in your property, then the best option is to request a dry rot survey as soon as possible.

How do I get rid of dry rot?

Getting rid of the infected materials is the first step in your dry rot treatment programme. You will need to contact a professional. Depending on the extent of your dry rot problem, you might need to remove a lot of structural timber from your home, so it’s best to have an expert on hand. If you’re not sure what you’re doing, you might damage the structural integrity of your property even further.

Any wood that has been infected by the fungus has to be removed and replaced. It is recommended that you also remove healthy wood from a metre surrounding the site of the original infection, and the new timber needs to be treated with a fungicide. 

It’s also a good idea to treat other structural timber in your home to prevent future infestations. The dry rot treatment will stop the mould spores from settling in again, even if the wood does accidentally get damp in the future.

If the dry rot problem has spread from the wood to the structural masonry, you will need to remove this too. The dry rot spreads by mycelium, which are like thin tentacles that spread through the damp materials. Once you’ve removed the affected plaster and mortar, keep removing until you’ve cleared a distance of one metre from the last mycelium.

Once you’ve repaired the damaged areas, it’s important to make sure the room is well ventilated, as this will help to dry out the damp patches. Please make sure the curtains are open during the day: dry rot likes warm, dark, and damp places, so plenty of natural light will also hinder its progress. You should also invest in a dehumidifier and put it in the room that was affected by the dry rot. This will keep air moisture levels at an acceptable level, and prevent the need for further rounds of dry rot treatment.

We have a wide range of Melbourne timber repairs for your home renovations. Check out Hitch Property Constructions.

Preventing dry rot in the long term

Dealing with the cause of damp in your property is the best way to stop the fungus from coming back. Dry rot only takes root in surfaces with a moisture content of 20% or higher. If this drops, the dry rot spores will become dormant. First, you need to find the source of the damp. The most common is condensation, which affects a fifth of British homes during the winter months. If condensation is the culprit you will need to reduce the humidity levels in your home; always use an extractor fan, and heat every room evenly.

The rarest form of damp is rising damp, which can also cause dry rot. Homes built after 1875 have damp-proof courses, which should stop rising damp from occurring, although in some older properties the course can become damaged or breached. Rising damp appears along the bottom of your walls, usually just above the skirting board. It can rise to one metre, so there might be tide marks left behind and a salty residue on the plaster. If your dry rot problem is being caused by rising damp, you will need to seek professional help to discuss an appropriate course of dry rot treatment. 

Cracked pipes within your internal walls, a breach in your home’s fascia that lets rainwater in, broken guttering, or a faulty appliance like a washing machine can also cause problems with damp, which can, in turn, lead to dry rot. Check your property thoroughly for any leaks or breaches. If your washing machine or dishwasher often leaks, consider replacing it. Make sure you clean your gutters at least once a year to stop them from overflowing or breaking. The key is to stop water from seeping into your property, preventing it from creating a welcome environment for dry rot.

The moment you see any of the above signs, it’s crucial that you do something about it. Sure, it might be easier to ignore the problem and hope it goes away, but it won’t. If you value your home, you ought to do what’s best for it. That means that you need to identify and seek a solution for these issues.

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