Cordwood construction is a type of building that involves stacking wood blocks together to form a natural wall. The walls usually use cob or mortar to secure the logs permanently. The technique is ideal when you want to use local materials and cut down the construction cost. This article highlights 7 best wood for cordwood construction that you can choose.
Before you go further, you need to acknowledge the factors that determine whether a particular type of wood is ideal for the construction. Some of the significant factors that determine the suitability of such woods include:
- Stability. It depends on its shrinkage and expansion. Both aspects are quite different and can bring a lot of questions. The baseline argument of these two aspects is that wood that can shrink a lot can as well expand a lot and vice versa.
- Insulation or the R-Value. Softwood is usually better insulators meaning that they have a high R-value. On the other hand, dense wood typically has a remarkable thermal mass but are poor insulators, which makes a low R-value.
- Rot resistance. It does not depend on the type of wood species that you are using. It depends on how well you consider the building principles needed to preserve the longevity of any wood.
- Consistency in dimension. This means the ability of a log to maintain uniformity from one end to the other. Wood that is excellent in cordwood construction, should have a regular shape to ensure the stability of the wall.
- Aroma. Wood such as aromatic cedar, has an aroma that stays in a house built using this type of wood. It also plays a significant role in keeping moths and other insects away.
With these aspects in mind, you are in a better position to evaluate a particular type of wood and determine whether it is ideal enough for the construction. Here is a list of the best wood for cordwood construction.
1. The Northern White Cedar
This marks the best type of wood used in cordwood construction. It possesses a lot of qualities needed for selecting wood for this kind of building. Its volumetric shrinkage is 7.2% and an average R-value of 1.25% on both end grains.
2. Aromatic Red Cedar
The red cedar is also known as the Eastern Red cedar. Its features include a volumetric shrinkage of 7.8% and a T/ R ratio of 1.5. Its heartwood is violet-brown or reddish. Aromatic red cedar with clear sections are not common, but the narrower types are readily available and sell at a modest price.
3. Red pine
Featuring a volumetric shrinkage of 11.3%, this kind of wood also marks one of the best types to use. The most notable aspect of it is its reddish-brown bark and its irregular shape. It also features an R-value of 1.04 % and 1.70% for its side and end grain.
4. Eastern Hemlock
Its heartwood is a light reddish-brown and has conspicuous rings that exhibit its growth pattern. Its features include a 3.0 % radial shrinkage, 6.8% tangential shrinkage, and volumetric shrinkage of 9.7%. The wood features one of the commercial types of hemlock used primarily for construction.
5. Virginia Pine
The Virginia pine features a volumetric shrinkage of 11.9%. It is well known for its red-brown scales and a needle-like prickle that matures in the fall. Its grain is straight and medium texture, making it ideal for cordwood construction.
6. Lodge Pole pine
The lodge pole pine is a light reddish or yellowish brown tree. The wood has a volumetric shrinkage of 11.1% and a T/R ratio of 1.6%. It is a widely available wood, meaning that it sells at a reasonable price.
This is a light brown type of tree prevalent in the central and Eastern United States. Its grain is usually straight and slightly irregular and has a medium texture with low luster. The wood has a volumetric ratio of 12.9% and a T/R ratio of 2.4%.
Now that you know the best wood for cordwood construction, it helps to know that the type of wood that you choose requires drying to reduce the possibility of shrinkage. For light, airy lumber, you should take at least a year while dense wood can take a few weeks. Reducing the shrinkage also minimizes the possibility of expansion, which is the most significant risk in cordwood construction.