7 Myths about building in wood

There are many misconceptions about building with wood. Some of these concerns come from bad construction practices of the past and others are truly myths and legends that seem to have no logical explanation. In this article we take a look at the 7 most popular myths about constructing a home out of wood. We will break them down and explain why they are not true and how wood can truly be a very advantageous material to work with.

1. If I build my home of wood, it will decay and fall apart.
   Built and maintained properly, wood structures will not decay. This is evidenced by the Hōryū-ji temple in Japan which has a 1300-year-old wood structure. What causes decay in wood is humidity which is the enemy of any structure. As long as the timber is dried properly and the building has good waterproofing and air circulation, there will be no problems with decay and rotting.

   Wood can even be used in exterior conditions where it will get wet, but it needs to be able to dry out and not stay wet for prolonged periods of time. The type of wood and its pre-treatment will affect how its color changes over time. Cedar, for example, is very age resistant. Untreated, it will also turn a silvery grey with time, but there are techniques that can be used to pre-age the wood so the color transition is minimal.

   ArchDaily has a nice article explaining more about untreated wood facades here: https://www.archdaily.com/974576/the-sobriety-of-untreated-wood-facades-tips-and-inspiring-examples

2. Insects will eat the wood and destroy my home.
   This problem is directly related to the one above, humidity. It starts with how the tree is treated as it is cut down. The bark must be quickly removed, and the wood stored properly. Modern timber production requires that the wood be inspected for insects and air or kiln dried to a humidity of less than 15% in which wood boring larvae cannot live.¹

   Cross laminated timber panels are assembled and cut to precision in large indoor halls where the humidity is also controlled. They are then installed on site in a matter of days during periods of good weather. Once the waterproofing is put in place and the building is sealed with a good forced-air circulation system, the wood will not become humid enough to attract insects.

3. Wooden buildings are a fire hazard and will burn quickly.
   Fire resistance is actually one of the major advantages of cross laminated timber structures, because the wood acts as it does when the tree defends itself against a forest fire. The outer layer of wood chars and in doing so protects the inner structural fibers of the wood. This greatly slows the burning down and means a mass timber structure will hold up to fire longer than steel.

   CLT panels can be produced with fire resistances up to 2 ½ hours.² Having this level of resistance on key structural panels gives people time to escape the building and fire fighters the chance to put the flames out.

4. A home made of wood will easily get torn apart in a bad storm.
   In a Clemson University study published in June, 2020, cross laminated timber structures were shown to withstand simulated EF-4 tornados which have winds up to 200 mph (321 kph) and tremendous uplift. It was determined that with thicker panels and more robust connections, the structures could withstand an EF-5 tornado event with winds up to 322 mph (518 kph).⁴

   The strongest recorded tornados in Europe have been EF-3 tornados and this past summer, the wind speed record for a storm was broken in the United Kingdom with gusts up to 122 mph (196 kph). Although storms in Europe seem to be increasing in strength, it is clear a CLT home designed and built properly will not suffer any more damage than a masonry home.

5. A wooden house is creaky and noisy.
   This myth has clear origins in the old homes built decades and centuries ago. Wooden planked floors were simply nailed to wood floor joists directly, and over time, those joints loosened. Walking across a floor like this causes the floor planks to abrade against the joists and nails. The Japanese mastered this in the exterior porches surrounding their palaces and temples. The squeaky floors acted as an alarm system and alerted the occupants to any intruders.

   However, modern sub-flooring systems assure that a new home will not squeak. Wood parquet floors are now applied to a layer of screed without nails, and if further sound insulation is needed, a layer of it can be added so that no one on the lower floor can hear footsteps overhead.

6. In summer it will be much too hot.
   This myth is a real mystery to those of us in the building industry who cannot figure out where it got started. Wood is naturally a good insulator against cold and heat. In fact, it has 10 times more thermal insulating ability than concrete or masonry, and it will not store heat like masonry, concrete or stone structures do when exposed over periods of time to sun and high temperatures.³

   In Luxembourg, it is required that walls meet a specified thermal resistance. This is always calculated by energy efficiency consultants who determine how much insulation needs to be added to the CLT panels. Typically, these walls are not as thick as masonry or concrete walls which need more insulation added to them. Designed and built properly, there is no difference between how cool a timber or a masonry home is in summer.

7. It will be much more expensive than building in masonry or concrete.
   This is a myth that unfortunately has had some truth to it over the past year. With sawmills being shut down in the pandemic and a sharp rise in demand, timber prices broke records in the summer of 2021. Those prices have since fallen, but with Russian and Belarusian timber being sanctioned, and so much global uncertainty, the markets are still volatile.

   This being said, the advantage of a CLT structure, as noted in myth number 6, is that the walls are thinner than in a masonry or concrete structure. This increases the living area of a home which in Luxembourg can add a great deal of value to the home and potentially offset or overtake the extra cost of construction.

   This is especially true when you also take the current price increases for the manufacturing of concrete, masonry, and steel due to the soaring energy prices. Before making a decision, it is always a good idea to first do a feasibility study of your project and continue doing a budget analysis at each design phase.

To learn more about building in wood, please download our free Guide to Modern Wood Systems for Your Home. You can find it here on our Resources page along with other helpful guides: https://saharchitects.lu/resources-home-design/