What timber does not rot?

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    Wooden benches, bridges, garden beds, and gazebos add character and warmth to outdoor spaces. Fungi and insects also love wood.

    Exterior wood must be weather-resistant. Some lumber is treated with chemicals to prevent rotting, and some is naturally rot-resistant.

    No wood is completely rot-proof, but many species can be used outdoors without chemical treatment. Others are moderately rot-resistant and may need regular or semi-regular treatment.

    Natural wood gives raised beds, fences, decks, and trellises warmth and texture. Chemicals prevent rot in much lumber. Some woods are naturally rot-resistant and can be used outdoors without chemicals.

    Cedar, redwood, cypress, and other rot-resistant woods are popular for decks, arbours, and saunas. Their chemical structure makes them immune to insect and fungal pests, and they have beautiful colour and grain.

    Naturally resistant woods don't last longer than pressure- or green-treated lumber. Here are some ways to make sure your expensive, natural wood lasts decades.

    Historically, homes used softer woods for siding, eaves, and trim. After rain, snow, and sun, these woods softened.

    Many fungi love softwood and moisture. In older homes, wood rot is common. Unchecked, wood rot can threaten your home's structure.

    You can make repairs before wood rot destroys your home. When you hire a home restorer, you can choose rot-resistant woods that will last for years.

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

    Why Use Wood Today?

    Wood surfaces are very intriguing from a design perspective due to the fact that their colour modulations, weathering, and variety of textures change over time. There is a wide variety of ways that wood can be worked to achieve a certain look, from rough log posts to decks that have been sanded smooth.

    One type of rot-resistant wood can be used in a variety of applications, and wood in general is known to exude an undeniable sense of warmth and to be associated with forests and other natural settings. When sourced locally and harvested in a manner that does not deplete natural resources, wood is an excellent material choice from an ecological point of view.


    How Does Wood Get Rotted in the First Place?

    Fungus is wood's enemy. Insects can cause damage, but they prefer wet, rotting wood. Termites and other wood-destroying insects usually follow fungi.

    Decay fungus destroys wood. Non-chlorophyll plants. They can't make food through photosynthesis, so they eat other things. They eat wood. Decay fungi destroy the wood's substance and strength.

    Decay fungi require four basic conditions to survive.

    Why Some Woods are More Resistant

    Why do some woods last well on your porch, while others seem to rot after one season? It has to do with the composition of the tree.

    • Amount of sapwood: the wood closest to a tree’s bark is a called its sapwood. On a cross-section of a tree, it’s that light-coloured layer, right before the bark. Sapwood generally does not have much decay-resistance, no matter what type of tree it’s part of. So, if a piece of lumber has a lot of sapwood, it’s going to have a low resistance to decay. And it won’t last long out there.
    • Amount of extractives: Extractives in the wood are what give it its colour, scent, and other physical and mechanical properties. They are the waxes, fatty acids, resin acids, and terpenes of a tree. Typically, if a tree grows slowly, it has more extractives and higher decay resistance. So older-growth trees tend to have more natural protection against rot.

    You do not need to be an expert on trees in order to determine which types of wood will provide the greatest resistance to rot in the event that it occurs. If you go to the lumber mill or hardware store in your town, an employee who is knowledgeable about woodworking will probably be able to point you in the right direction and help you get started.

    It is a good idea to have some idea of the type of wood you want before you head out to the store to look for lumber that is resistant to rot. When all is said and done, different types of wood will have distinct characteristics in addition to their resistance and longevity. These characteristics include colour, grain, texture, ease of working with, availability, and, of course, price.

    The World’s Most Rot-resistant Woods

    Some naturally durable woods are rare. Some tropical woods resist decay. Warmer temperatures and higher humidity in the tropics prevent decay. Exotic woods are more expensive and harder to find than domestic woods.

    In order from most to least resistant to decay and rot, these woods are listed with information about how easy or difficult they are to work with and other physical characteristics that may make them desirable for certain projects.

    Softwood attracts insects and rot. Termites prefer soft, wet wood, so you'll find damage in waterlogged old homes. Soft pine, fir, and other white woods used in most homes today offer little termite and rot protection.

    Why don't we build with rot-resistant wood? It's too expensive. Use rot-resistant wood like the options below to prevent rot.

    Repairs can use rot-resistant wood (especially exterior repairs). Interior trim and mouldings, hardwood floors, and mantles don't need the same protection as siding, exterior trim, porches, and decks.

    Here are some rot-resistant wood options and why they may work for your project. Region-specific availability and pricing. So do some local research to find out what's what.

    Moderately Rot Resistant Wood


    This type of wood can be found in great quantities across the south-east. It is very easy to work with, has a low price point, and is excellent at accepting both paint and stain.


    The western United States' version of the cypress tree is known as the redwood. A type of wood that is commonly used for exterior construction because it is easily obtainable and relatively inexpensive.

    Old-Growth Pine

    Pine is not a naturally rot-resistant wood; however, old-growth pine provides a significant amount of rot resistance in comparison to younger pine. This type of wood is frequently used for the shiplap siding and other decorative elements that adorn the exterior of older homes.

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

    Rot-Resistant Wood

    Old-Growth Cypress

    The version of this resistant wood that comes from old-growth trees has significantly more heartwood than its relatives that come from new or second-growth trees. As a result, it is much more durable and has a much higher level of resistance to rot and insects.

    Cedar (Eastern White or Western Red) 

    The use of cedar in exterior construction is highly recommended. Cedar is an excellent choice for finishing with stains because of its naturally beautiful grain pattern. Because the resins in cedar have a tendency to bleed through paint, it is imperative that you use a stain-blocking oil primer if you intend to paint the surface.

    White Oak 

    White Oak is a type of domestic hardwood that is known for its extreme durability and is readily available in the United States. Windows, doors, high-quality furniture, and floors made of wood have all been crafted with this material for centuries.

    Old-Growth Redwood

    Once again, the old-growth version of this wood is very resistant to rot and insects.

    Pressure-Treated Pine

    Quite possibly the most easily accessible and decay-resistant type of wood in the United States. It is very resistant to rot and insects and can be purchased at any home improvement store. It is resistant to rotting even when put in direct contact with the soil, and it has a good capacity for holding paint. Because of the chemicals that were used to treat it, you will need to wait a few weeks after installation before painting it. This is because the chemicals need time to dry out. Caution is advised because after it has dried, it will shrink quite a bit.

    Extremely Rot-Resistant Wood


    This species reigns supreme among hardwoods. It has an extremely high density and a very high hardness, both of which help to repel pests and water, thereby preventing rot. Because mahogany is so attractive in its unfinished state, it is frequently used in the construction of doors. In addition to that, it holds paint very well. However, due to the fact that it does not rot and has beautiful characteristics, it can be quite expensive.

    Spanish Cedar 

    The Spanish Cedar has a texture and appearance very similar to mahogany, and it is also very dense. Since it is very stable, it is an excellent option for use in window frames and exterior trim, despite the fact that it is not as hard as mahogany and does not cost nearly as much. In recent years, it has become increasingly difficult to locate this type of wood, but it is possible that it is still accessible in your region.


    Because it is one of the hardest woods available, a rock-hard tropical wood that is excellent for use in the construction of porches and decks. Because of its high hardness, the wood can be left unfinished and exposed to the elements without deteriorating. Due to its extreme hardness, cutting and milling it is an extremely challenging and time-consuming process. Because of its toughness, you will need to pre-drill any holes for the fasteners.


    This wood, much like teak, is extremely dense and dense, making it an ideal material for use in decking and porches. If it is kept oiled, the deep red colour will retain its beauty for many decades and look stunning outside.


    It is said that this type of wood, which is relatively new to the market, is almost completely resistant to rot. Acetylation is performed on Radiata Pine, which is an essential ingredient in the treatment process. The wood undergoes a chemical transformation during this process, which results in the wood becoming exceptionally dimensionally stable (it won't shrink or twist), unattractive to insects, and exceptionally rot-resistant. Accoya is not treated with any harmful chemicals, in contrast to wood that has been pressure-treated. This article will provide you with some additional information regarding Accoya.

    Using Wood Outside

    Outdoor furniture

    If you view your purchase of chic outdoor furniture as an investment in products that will hold up well over time, then the higher price tag may be justifiable. Everything decomposes in due time. In addition, I am sceptical of products that claim to have exceptionally long lifespans because I am afraid that these products, like Wonder Bread for outdoor materials, are packed full of chemicals in order to extend their storage life.


    The fact that smooth wood is such a pleasant material to walk on with bare feet explains why it is so widely used for pool decking and for areas near outdoor showers. A builder or carpenter with experience will have a great deal of familiarity when it comes to the process of constructing wood elements that do not accumulate water.

    Wood post fences

    A home landscape can be given a nice handmade appearance by incorporating a wood post fence with a rough texture, such as this ash juniper post fence. A relaxed atmosphere is achieved by using wood that has not been sanded smooth or fashioned into perfect beams.


    Plants that are allowed to grow on a wooden trellis will eventually cause the wood to rot because the plants will retain moisture and allow the wood to become more susceptible to decay. On the other hand, a wooden trellis can have the appearance of a cottage garden, whereas a trellis made of metal cannot achieve this effect. Because they will not attempt to attach their roots to the wood, twining-type vines that wrap around structures, such as clematis, are a better choice for a rot-resistant wood trellis than other types of vines.

    Raised beds

    It is a good idea to place raised cedar beds on gravel rather than soil because the gravel will quickly drain water away from the cedar and will not retain moisture. A geotextile or landscape fabric can be used to create a barrier between the bedding soil and the wood on the interior of a raised bed. This helps to wick moisture away from the wood, which in turn extends its lifespan.


    Not only as the primary component of a deck or pergola can wood be used in the garden, but also as a decorative element in the space. Woods such as ipe and redwood are frequently used for crafting intricate details. It is possible to prevent the wood from coming into contact with the ground by incorporating it into the railing or bench that is made of metal and adding a special finishing touch using wood.

    How to Stop or Prevent Rot

    Even rot-resistant woods can become susceptible to decay if allowed to age or if subjected to particularly harsh conditions. In such circumstances, the question becomes: how can wood rot be prevented?


    If you’re using a block of wood outside, starting with a rot-resistant wood is the most important step. From there:

    • Limit ground contact. When a block of wood is in direct contact with the ground, it opens the wood to mould and fungus because it allows moisture to penetrate the wood.
    • Pitch the wood so that water does not collect on the surface.
    • Remove plants and vines that grow over the wood. They accelerate rot due to moisture.
    • Use chemical wood preservatives to deprive fungi of its food source and make wood inedible to decay fungi.
    • Keep it painted or stained to help keep out water.
    • Remove any standing water.

    The better you are able to prevent moisture from getting into the wood, the less likely it is that fungus will take hold of the wood in your outdoor space and on your outdoor furniture. It is much simpler to prevent rot from occuring than it is to cure it once it has already begun.

    Pressure-Treated Lumber

    The term "pressure-treated lumber" refers to a type of lumber that has been through a process that infuses a chemical preservative into the wood at a deeper level. When the wood product is put into a large holding tank that is then depressurized to remove all air, this step of the process is referred to as the "pressure" step.

    A preservative is added to the tank, which is then pressurised to a level that forces the chemical to penetrate the wood to its core. After that, the tank is emptied, and any remaining preservative is put to another use. After being removed from the tank, the wood is then processed in preparation for delivery to the nearest lumberyard.

    Because of this chemical, treated lumber is resistant to fungal growth and insect infestation, which results in the wood having a longer lifespan. After that, it can be purchased as lumber, boards, posts, or plywood in its various forms.

    A Wood for All Seasons

    All through the year, pressure-treated lumber is an excellent choice for use as a construction material in outdoor settings. It is safe to assume that a piece of furniture, a swing set, a swing, a deck, a mailbox, a picnic table, or any other exterior wood project or product made from pressure-treated lumber will last for many years, whether you build it yourself or buy it.

    Is Chemically-treated Wood Safe?

    When you hear the words "chemically treated," you might start to wonder if the wood in question is safe for use around children and pets, as well as in gardens and indoor spaces.

    The Environmental Protection Agency (EPA) is in the process of reexamining the kinds of pesticides that are used in pressure-treated wood. These substances are known as chromated arsenicals, and they contain chromate copper arsenate (CCA), which belongs to the arsenic family and is known to cause cancer. The EPA has already placed restrictions on a great number of CCA applications.

    Today, Alkaline Copper (AC) and Quaternary Ammonium Compounds are used to treat wood that has been subjected to pressure treatment (ACQ). These compounds have been shown to not leach into soils like CCA and creosote have, despite the fact that they are significantly less toxic. The health risks are significantly reduced as a result of this, but they are not eliminated.

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

    General Safety Tips for Chemically-treated Wood

    • Wash children’s hands after they have been in contact with treated wood
    • Do not put food directly on a treated wood surface, like a picnic table.
    • Do not use treated wood where it may come into contact with edibles, such as in a garden.
    • Never burn treated wood – indoors or outdoors. Burning this type of wood releases chemicals in the ash and smoke.
    • Do not use treated wood near livestock, feed, or food-producing animals.
    • Do not use treated wood where it may come into contact with drinking water.
    • Do not place treated wood or sawdust in a compost bin, and do not use it as mulch.
    • Do not use bleaching or cleaning agents such as sodium hypochlorite, sodium hydroxide, sodium percarbonate, citric acid or oxalic acid on treated wood. These can cause the wood to release chemicals that may be inhaled or come in contact with skin.

    The primary contributors to the process of wood rot are the presence of moisture and exposure to sunlight. In addition to this, organisms such as insects, fungi, and others can cause damage to wood. When the wood is in direct contact with the soil, as it would be in a raised garden bed or a vine trellis, it is especially important to make use of rot-resistant wood in outdoor construction.

    Ground contact exposes the wood to the dangers of mould and fungus because it lets moisture seep into the wood, causing it to swell and crack as a result of the reaction. There are ways to build that keep you from having to make contact with the ground, and there are ways to stack wood that prevent water from pooling on the surface. Because of the accumulation of moisture, plants and vines that grow over the wood speed up the process of rot.

    FAQs About Wood Rot

    Sand the damaged area with medium-grit sandpaper, following the direction of the wood grain. The goals are to smooth the wood, remove loose paint, and prepare the surface for accepting new primer and paint.

    Moisture can easily cause rotting and splitting in wood, and a new coat of paint will not do anything to fix the problem. When water soaks into wood, it can cause wood to expand and swell as well as deteriorate to the point of falling apart. So, painting over the problem only won't fix it, it will just add to it.

    Use a polyester filler to rebuild rotted or damaged wood. You can mold and shape it to match the original wood profile. It takes paint well and won't rot.

    Dry rot is a type of dampness primarily found in aged homes and buildings. If left untreated, it can cause wooden structures to weaken and the building's foundation will get disturbed.

    If the wood can be salvaged, the first stage to dealing with decay is to cut out the affected area. If the wood is wet, allow it to dry before filling with a wood filler such as Cuprinol Ultra Tough Wood Filler. For best results, pre-treat the repair area with Cuprinol Clear wood preserver and allow it to dry.

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