Timber Preservation in Spean Bridge

This is one of most common and discussed dampness found in building. In recent times, condensation is the most common form of dampness, however positive identification and the right corrective action for both is vital. Rising damp is simply referred to as the flow of water upwards and vertically through permeable wall structure, the water being gotten from the ground. The moisture rises via the capillaries or pores in the masonry, meaning that the masonry functions just like a wick. With rising damp, water rises through the mortar beds and through the bricks. The mortar forms the only continuous pathway for the moisture to rise up the wall. Even if a house is built from impervious bricks then moisture can still rise through the mortar beds, however if an impervious brick is incorporated then water will not rise even if the bricks happens to be quite porous. In other words, mortar beds are an integral element in the chemical treatment for rising damp.

The moisture coming from the ground features small quantity of soluble salt which includes nitrates, chlorides as well as sulphates. These are transmitted with the water up the wall and are deposited and left behind when the moisture evaporation when drying. After some time, the salts will slowly accumulate and form a salt band close to the peak height of the rising damp. Chlorides and sulphates absorb water from the environment. Overall, the higher the quantity of salts, the greater the absorption of moisture from the environment and even more so when under humid conditions. In other words, even if rising dampness has been controlled by the installation of damp proof course, these salts can still make the wall and any affected decorations to remain damp.

Wet rot simply refers to the decay of timber caused by high moisture levels. This natural decay occurs when the moisture content in timber is about 30 percent to 50 percent. This is opposing to dry rot which only occurs as a result of a lower moisture content of about 20 percent. Naturally, a fungus is attracted to very damp wood, which it feeds off and in turn, destroying it. There are a number of fungus types, however the most common type is Coniophora puteana (also referred to as cellar fungus). In general, wet rot is usually confined to a localised damp area and does not spread which makes it a lot less destructive when compared to dry rot. However, if left untreated or totally ignored, wet rot can be just as destructive as dry rot and can greatly reduce the structural strength of the timber thereby causing a major structural damage in the process. So, what causes wet rot? Let’s take a look!

First and foremost, it must be stated that wet rot would be non-existent without a damp area to grow and thrive as wet spores are attracted to wet timber with a high level of moisture content. This moisture can be as a result of a number of issues which includes defective plumbing, leaking gutters, leaking roof, broken pipes, leaking washing machine or a leaking shower tray or bath. When the moisture a timber is exposed to is excessive, this offer the perfect environment for the growth of wet rot as it enables fungal spores to germinate and grow. They use the wet timber as a food source and eat it away, leading to a weakened wood and a compromised structural integrity.

Also commonly referred to as brown rot, dry rot simply means a decay of the root as a result of fungi which may negatively impact the wooden structures in the interior or exterior of your home or property. When the dry rot happens, the fungi present breaks down the cellulose as well as hemicellulose – the components which are responsible for the strength and resilience of the wood. Consequently, the wood is left weakened and brittle while also appearing a bit blocky. Most often than not, dry rot affects damp timber, primarily with a moisture content that’s more than 20 percent. As a result of this, any dry rot eradication strategy should have the removal of the source of moisture to form the core of its activities. So, how can you identify dry rot? Let’s take a look!

• Examine the wood. At first, the fungus appears a lot similar to cotton wool and may also possess water droplets on its surface if there is a very humid surrounding.
• Look out for shrunken or sunken wood.
• Identify darkening and cracks in the structure of the wood.
• Identify affect wood that features flat skin-like grown that may appear like the exterior of a mushroom with shades of silver and grey. Most times, patterned with patches of light purple or yellow which easily peels.

Dry rot can be treated in a number of ways which includes epoxy treatments, commercial anti-freeze as well as copper compounds. The epoxy treatment simply means the act of filling in channels within the damaged wooden structure with an epoxy treatment to eliminate the rot and strengthen the structure of the wood. The commercial antifreeze is the treatment of the rot with antifreeze to kill the fungus and prevent further growth.

The most serious form of fungal decay is dry rot which occurs when the moisture levels of a timber is about 20 percent. It targets timber in buildings and feeds off the part of the wood which gives it its strength.it is able to produce moisture through the digestion of timber and as a result, does not require any source of moisture to spread. Once the dry rot is able to spread, it can severely impact and compromise the structural integrity of the house or building. If you think you may have dry rot on your building, the best solution would be to call on a professional to conduct a survey of your premises and have it treated as soon as possible if positive. If the dry rot is not identified and treated as soon as possible, you may have to remove and replace all the affected timber later on. In this post, we’re going to take you through the process of treating dry rot by yourself. Let’s take a look!

• The initial treatment stage of dry rot is to identify the moisture source and have it repaired. Once done, you’ll have to ascertain the full extent of the dry rot outbreak. To achieve this, simply open up the affected area by removing the plaster and render in all directions while also removing flooring and lifting floorboards. Once done, you should be in the best position to determine the full extent of the infected timbers.
• Proceed to cutback the timbers in-situ to a minimum of 500mm beyond the last signs of fungal growth or the strands of hyphae.
• Remove all fruiting bodies and detectible spores. Clean the wall areas to eradicate surface growth using a stiff brush if necessary.
• Replace the timber with pre-treated timber.
• Treat the new and old timber with a dual purpose dry rot treatment fluid and sterilise the masonry.