Wood is a wonderful and versatile material and lights the kindling of creativity. This article isn’t about wooden houses, but rather the use of wood within designs and construction applications.
Exceptional insulator and energy saver
Some building materials such as steel and inorganic materials which are non-combustible, expand when heated which can weaken and collapse the structure. Wood reacts in an almost opposite manner to this. When heated (not excessively to a combustible temperature of course), wood dries and actually becomes even harder.
Let’s make some comparisons here. Glass conducts heat 23 times faster than wood, marble 90 times faster, steel 1 650 times faster and aluminium a whopping 7 000 times faster.
This means less energy leakage from your design. If you want the warmth (or coolness) to remain, and you want to spend less money on heating (or cooling), wood is a tremendous alternative to brick, concrete or stone. Compared to other construction materials, wood is economically a star material in insulation.
Fact: Wood actually does expand slightly when air humidity drops below 0%, however this won’t affect the constructors amongst us as even in the most parchedness of climates, humidity doesn’t drop below 5%.
Quick to build = money savings
“People love chopping wood. In this activity one immediately sees results,” – Albert Einstein. Looks like he hit the nail on the head there. People like quick inexpensive results, and that’s exactly what wood offers in construction applications.
Some wooden building manufacturers and installers can construct a 100m² unit, on site within 7 days. Imagine popping to your favourite holiday destination for two weeks, then returning home to discover a new building has sprung up in your neighbourhood. This is indeed impressive!
When compared with brick and mortar, wood construction certainly does save time, and inherently with that come savings. This is especially applicable in harsh weather conditions such as heavy rain, and icy conditions, where wood construction can continue without hindrance unlike other traditional methods.
Wood-framed buildings also enable easy modifications during and after the building process and it’s because of the ease, versatility and cost effectiveness which makes it such a popular and inexpensive choice.
Green is the biggest topic these days, so of course this is going to be a big plus for timber. Buildings made from trees are sustainable, renewable and environmentally friendly. As you may already know, wooden structures absorb and store atmospheric CO² and that wood, even taking into account haulage, is carbon neutral (in fact, it’s the only carbon neutral construction material).
Most westernised countries have legislation where at least one tree has to be planted for every tree which has been cut. This is significant because it means there will be more wood on the planet, which means more carbon absorption. Let us not put our blinders on though, deforestation is a despicably saddening fact, therefore make sure your source of wood isn’t questionable.
Mature trees actually absorb less carbon than younger, faster growing trees, therefore it could be beneficial in the battle on climate change to cut the older trees, use them in construction and plant new carbon munching trees in their place.
Fact: 0.8 tonnes of carbon emissions are saved for every cubic metre of wood which is used in construction, therefore, if a building uses 20 cubic metres of wood, that’s a saving of 16 tonnes in carbon. In context, 16 tonnes of carbon is the same amount of carbon produced by driving 90 000 kilometres (as a very crude estimate). Using wood in construction, whether it’s a complete construction of just the wooden frames, really does have a positive impact on climate change.
With over 5 000 different woods to choose from, there will definitely be something that will suit any construction or design needs. Some woods are ideal for insulation, some for acoustics, grain, colour, appearance, and others for structural frames, walls, floors, ceilings and furniture.
You may agree that the grain on a piece of wood is one of the most mesmerizing beauties in the natural world, where different hues of colour and textures roll back into each other like an enchanting dance. Some of the most breathtaking architectural designs are wood centred.
Wood can be painted in any colour and can be waxed, and varnished which emphasis its natural finesse. It can be carved, cut, glued and nailed.
Wood is so versatile and aesthetically delightful, the only limit to what you can make with it is restricted by one’s imagination. Just like Albert Einstein has said, ‘Imagination is more important than knowledge’ and, ‘Imagination is everything. It is the preview of life’s coming attractions’.
Mechanical properties and working properties
To test the hardness of a given wood, the Janka test measures the force required to embed an 11.28mm steel ball halfway into the wood.
The hardest wood is the Australian buloke which requires 5 060 pounds of force. One of the softest woods is from a cuipo tree, which requires 22 pounds of force, far softer than the better-known balsa wood which comes in at 100 pounds.
Wood, although light has a remarkably high tensile strength. Let’s take wood which has a tensile strength of 0,6/cm³ and the specific gravity is 100 N/mm2, as well as steel which has a tensile strength of 7,89/ cm³ and the specific gravity is 500 N/mm2.
If we divide the tensile strength by the gravity, the given figure will tell us the quality of the material and its breaking length. The ‘breaking length’ means the point at which the material breaks under its own weight. Steel which is used in buildings has a breaking point of 5.4km and hardened bow steel 17.5km.
When we compare the tensile strength of steel to two varieties of wood, spruce and laminated beech, the respective breaking lengths are 19.8km and 28.3km. Now you know why laminated wood is used on the floors of sports halls!
When it comes to how workable wood is, few things can surpass it. Wood can be whittled in beautiful and creative ways, which can make for almost magical designs. The accuracy and finish that can be achieved with wood can help carve an ordinary design into something extraordinary. Further to that, wood is fairly easy to maintain and to repair, so if it goes wrong, fixing the problem won’t burn a big hole in the client’s wallet.
Safe, light, sturdy and durable
One of the many reasons why wood is still used today, despite huge strides in engineering excellence, is its durability weight and safety.
Wood has a little bit of give in it which means it can bend slightly, which is a property which bricks don’t have. Therefore, if the foundations shift slightly, a wooden building can flex and move with the change rather than crack. Even the smallest shift in the foundations of a brick house will cause cracks to appear in the mortar (not a good look).
In areas where soil is weak wooden buildings are a perfect solution. Heavy brick construction can cause the ground to sink, and nobody wants to become the victim of a building sinking.
Wooden houses are prevalent (and sometimes required) in the south east because they are cheaper to rebuild if destroyed by a natural phenomenon such as hurricanes.
While many woods soak in moisture and water, causing them to swell, there are some varieties of wood which are highly water resistant. A study has been conducted into the absorption rates of four different varieties of wood, Western Red Cedar, Douglas Fir, Western Hemlock and Sitka Spruce.
The woods were dried so that their moisture content ranged from 6-10% and were then left outside, covered. After one year, the moisture level of Western Cedar was between 9-11%, while the others ranged between 14-21%. The increase in moisture absorption from the untreated cedar wood was minimal.
This study demonstrates that even though some woods have a tendency to absorb moisture, there are particular varieties of wood which will not have that tendency. There are some woods which are used specifically for their high absorption rates, and some, such as cedar for their low absorption rate.
Healthy and natural
Electrostatic charge: This is a big deal for some people as electrostatic charges are believed to be unhealthy to some degree. Wood emits zero electrostatic charge; nada, zilch!
If a room is finished with an uncoated wood, it will help regulate the humidity which could aid in helping people with respiratory sensitivity. Not only does it regulate humidity, just the mere look of wood can sooth one’s mind and relax the nervous system. Just make sure the humidity doesn’t make the wood too moist, otherwise that static electricity benefit could be thrown out the window.
For these reasons, wood is deemed to be a healthy choice over metal, plastic and other materials.
Even though wood doesn’t act as a perfect sound insulator, it does prevent echoes from bouncing around the room by absorbing sound waves. When compared to its constructive competitors, wood proves to be much more effective at sound insulation, especially when it comes to insulating between different rooms.
Wood is also used in many concert halls around the world as it naturally dampens sound, creating that perfect tone within the room.
Rust be gone
Last but not least, wood doesn’t rust. Even though it can oxidize in some form, it is statistically insignificant when compared with metal. True, there are some metals that don’t rust, but they’re more expensive; and can you really criticize wood after we’ve learned how wonderful it is!