Preventive treatment against fungi, mould and wood-boring insects

Prevention is better than cure. The expression is commonly used in medicine, but it is perfectly valid for wood. It's much easier to make sure wood is protected against fungal, mould and woodworm attack than to treat it when it's already infested. Treatments to save attacked wood are often aggressive, time-consuming and sometimes the attack is so extensive that it is impossible to save the wood. Even more so, wood needs to be treated if it is used in construction, in structures covered with other materials. Signature Deposibin Sibiu offers treatments, both for prevention and for infested wood. Bochemit Opti F+ is used for the preventive treatment of wood against fungal, mould and insect attack.

Favourable conditions for fungal and mould growth

Insect and fungal attack on wood occurs when conditions are right. What are favourable conditions? High humidity, temperature suitable for the development of organisms and poor ventilation (lack of air circulation). Let's take them one by one.

Humidity The wood balance is 8-12% for wood used indoors and 14-18% for wood used outdoors. If conditions occur that favour exceeding these limits - seepage, condensation, flooding, water splashing - the wood will absorb water, its moisture content will increase and it will be favourable to fungal growth and insect attack. High humidity is the main cause of wood infestation.

Indoors, if the humidity exceeds 18-20%, conditions become perfect for fungal growth. The problem is that once infested with some fungi, even if the humidity drops, they will find a way to protect themselves, survive and spread on the wood. Over time, the strength of the wood decreases and can become a problem, especially if it is part of the load-bearing structure. And it's not just about timber frame houses. Houses have, for example, timber framing, even if they are concrete or brick. Weakening its strength can lead to pitching or even collapse of the roof.

Temperature 20-24°C is perfect for fungi and insects to grow in high humidity. But fungi can grow from 0°C up to 36-37°C, the normal human body temperature. There are, however, fungi that can survive at low temperatures for long periods of time. As soon as the temperature returns to a temperature suitable for growth, they reactivate and begin to expand. High temperatures destroy all fungi, but it is difficult, sometimes impossible, to treat infested wood in a building in this way. The high temperature should be maintained for a long time so that the heat penetrates deep into the wood.

Air circulation is one of the basic laws for keeping wood dry and healthy. If by chance water gets into certain areas, air circulation will allow it to dry quickly, protecting the wood. If there are air vents in the house, don't cover them because of draughts or cold air coming in. You could do a lot of damage to the building. Indeed, fungi need air to grow and breathe. Attack does not occur if the wood is submerged in salt water or other airless environments. But air currents are not good for the fungus; it thrives better in spaces where air is not circulating.

The condition for a house not to be infested by insects, mould or fungi is that it is well designed, executed and maintained. In such a house the possibility of condensation is non-existent, and the increased humidity that occurs accidentally will disappear quickly enough to leave no room for infestation.

Wood-attacking fungi

Wood-boring insects are a serious problem for wood lovers. And in order to present as much information as possible, we have "covered" the subject in several articles. You can see herewhy cavities occuras well as antique solutions inhow to get rid of curries and other wood pests

The subject has been covered extensively here and here, so now we're talking about mushrooms. There are 5 groups of fungi that grow on wood:

• brown rot (house sponge, basement fungus, brown rot)
• white rot (causes white spots on wood)
• soft rot (used in some industrial processes)
• stains (only causes discoloration, does not attack the strength of the wood)
• moulds (surface formations that help to identify places with high humidity, conducive to fungal attack).

Household sponge or tear fungus (Merulius Lacrimans) is considered one of the most dangerous fungi for all softwoods, but it can also damage hardwoods, even oak. It feeds on cellulose, providing the moisture needed for growth by decomposing it. It can also attack other materials containing cellulose - paper, textiles, insulation materials. House sponge spreads especially to floorboards, joist ends, floorboards, door and window frames, the back of panelling and roofing. It can extend to masonry and plasterwork and can penetrate walls over 1.5 m thick. It grows very rapidly and produces abundant white mycelium with thick grey-brown threads.

Basement mushroom (Coniophora putanea) is one of the most common fungi that can grow in homes. Favoured locations are damp, unheated spaces in basements, floors or roofs. It spreads rapidly and can even reach neighbouring houses. It is very dangerous because, once it is established, it is impossible to stop because it passes through masonry from room to room, even from building to building. It attacks hardwoods and softwoods equally. It produces black, branched, fan-shaped mycelium (the main identification criterion), decomposing wood as brown prismatic rot.

Brown rot (Gloeophyllum) occurs mainly in exterior softwoods, but also in house construction. It mainly attacks floor beams, joists and joinery. It produces intense brown rot inside the wood. Even when the attack is intense, the outer surface of the wood remains unchanged.

Bochemit Opti F+ from Deposib, a product that helps prevent problems from occurring

Bochemit Opti F+ is equally fungicidal and insecticidal, being a concentrate in liquid form. It is used for long-term preventive protection of wood against fungi and harmful insects. It is very suitable for treating wood used in construction (floors, panelling, wainscoting), but also for wood used in outdoor landscaping (pergolas, gazebos, fences). It is recommended for the treatment of class 1, 2 and 3 construction timber according to EN 335. The treatment can be used for both new and old wood.

Main product features Bochemit Opti F+ are:

• Long-lasting protection
• A concentrated product that dilutes with water
• Can be used for both indoor and outdoor wood
• Easily applied by brushing, dipping or pump spraying
• It has a basic pH between 10 and 11.5
• No specific odour (and no treated wood)
• Can be used on wood with high humidity up to 40%.

The treatment is done on clean wood from which traces of processing have been removed and stripped or which has been cleaned of old layers of paint. For brush or spray application, the dilution is 1:9 with water. For immersion, the dilution varies between 1:6 and 1:19, depending on how long the wood has been immersed. Consumption depends on the absorbency of the wood. In case of brushing or spraying 1-2 coats can be applied. The second coat is applied only after the first has dried. Opti F+ is the improved, more concentrated version of Opti F, which protects a larger surface area (66 m²/kg of Opti F+ compared to 57 m²/kg of Opti F).

Wood treated with Bochemit Opti F+ is not filmy and the product is absorbed deeply. After drying it can be finished with products commonly used for interior or exterior wood finishing. The product is available in clear, brown or green. The transparent version does not cause yellowing of the wood. You can find it packed in 1 kg, 5 kg, 15 kg and 50 kg and the prices are here.

Bochemit Opti F+ Preventive protection against all natural wood pests (fungi, insects, mould), both indoors for the lifetime of the wood and outdoors for up to 10 years. For longer term protection on the outside, we recommend applying Bochemit Estetik protective oil coloured, which protects against all environmental factors (UV radiation, rain, freeze-thaw, wind, etc.). Bochemit Estetik Protective Oil enhances the natural grain of the wood giving it a pleasant appearance and moisturises the wood, preventing cracking.

Product used and appreciated in numerous public and private projects

Preventive treatment with Bochemit Opti F+ has proven its qualities over the years, both on wood used in old projects, some of them with historical significance, and on new, private projects. Here are just a few examples:

• The largest round log cabin in Romania (on Transalpina),
• Wooden hut at the highest altitude in the country, 2100 m, at Bâlea lac,
• Largest pontoon for events on Lake Tarnița,
• The most beautiful swimming pool, at Cheile Grădiștei,
• Casino in Vatra Dornei,
• Historic buildings, over 300 years old, from all over Romania.

It is used as a preventive wood treatment product in 7 of the country's museums. The most recent project with Bochemit Opti F+ if Bochemit EstetikThe ongoing project is to protect the structure of the Dacian Fortress of Costești, in partnership with the Ambulance for Monuments, the Prince Charles Association and numerous volunteers, architects and architecture students. We will come back to the subject when the project is ready. Until then, a few pictures to give you an idea.

Bochemit products has been manufactured in the Czech Republic for more than 50 years and its parent company, Bochemie, has been producing chemicals for more than 110 years. Deposib Expert imports the products from the Bochumin factory in the Czech Republic and distributes them throughout Romania via authorised distributors.

As I said, prevention is better than cure. It's cheaper and hassle-free.