When you start to plan your Timber Frame project, one of the biggest questions you’ll have to answer is what species of wood you want to use for your frame. The wood species you choose will affect the price of your frame, the dimensions of the wood members, and other structural and engineering characteristics. So deciding what species of wood is right for your frame and for you is a decision that needs to be made early in the process. Today we’ll look at some wood species that are common in Timber Framing and a few that aren’t used as often but are still options to consider.
Fir is an excellent wood for highly finished post & beam frames and commercial work because of its strength and beautiful grain. It is one of the most abundant wood species in North America and is one of the most popular choices for Timber Framing. Its color ranges from light red to pale yellow. We buy our Douglas fir timbers directly from west coast suppliers who select only the best looking timber. Douglas Fir is available free of heart centers, which means that the usual “bull’s eye” heartwood found in the center of most timbers is absent. Free of heart timber is less prone to checking and is more stable than timber which does have heartwood. We don’t recommend having your Douglas fir hand hewn because when you try to create that finish with Douglas fir it tends to peel and doesn’t look its best.
Hemlock is a great economical wood for country homes and barns. It is pale in color and naturally develop a richer appearance over time. It looks great rough sawn and hand hewn. Hemlock is very strong, has a long grain and is a renewable resource. It is resistant to rotting and it is also much less expensive than Douglas fir. However, certain stands of hemlock can have a defect called shake. Shake is a delamination between the timber’s growth rings. We order our hemlock shake-free. However, shake will often show up after a timber frame has been up for a year or so. Shake in timber frames is generally not a structural problem. Our engineers design frames that can account for shake, checks and other movements of the wood over time so shake in Hemlock is generally not a structural concern and it can make a post & beam frame look rustic.
Pine is a very stable wood. It has a good straight grain, can be easily stained, planes well, and is a great wood for hand hewing. Because it is less expensive than Douglas fir, it is often used for residential timber frames. It is similar in color to hemlock – a pale yellow with occasional reddish streaks. Pine is not as strong as hemlock or fir, so it is not a good wood when long spans are required or when smaller beams are desired.
Oak is a very strong & beautiful hardwood. It tends to be more expensive than pine or hemlock, but less expensive than Douglas fir. Hardwoods, in general, are not as stable as softwoods, which means they tend to twist and check more. Oak, in particular, is subject to surface checking – when a timber gets many little, tiny splits & cracks just on its surface. Heart checks are also prevalent in oak. Some of our clients love that the oak is native to our area, and the timber doesn’t have to travel as far to get to our workshop to be finished. There are different types of oak: white, red, and mixed. White oak is very weather resistant and Red oak is a little redder in color than white oak. Mixed is exactly as it sounds, a combination of red and white. Ordering mixed oak saves time and money.
Cedar is a naturally white or red colored wood. It can be stained with a natural oil, or stained dark depending on the owner’s preference. Cedar is naturally rich in oils that preserve the wood when exposed to the weather, making it perfect for exterior use. Cedar is naturally resistant to rot and to insects as well, making it an especially hardy and long-lasting wood.
The Cypress trees generally grow in warm, wet climate. They are a common southern tree and have a distinctive look and odor when they are cut. Younger Cypress trees are moderately hard, stable, and strong, and are resistant to decay so they are good for indoor and outdoor use. The wood contains natural preservative oils so it can last for a very, very long time. Cypress holds resins and glues very well. It also planes well. It is less expensive than Douglas fir and is comparable in price to Oak.
Reclaimed Wood is timbers that have been taken from old buildings such as barns, mills, factories and other structures. People love reclaimed wood because it is recycled, making it a green building material, and because it has a very specific look to it. Because reclaimed wood is generally old growth timber that has often been aged for 100 years or more, it has a beautiful tight grain which can be exposed by resawing the pieces. It also has a lot of rustic or vintage character when it’s used as is. When we place an order for vintage wood, we specify either “hand hewn” timber or “resawn” timber. The resawn timber is cut with a band saw to our requirements. The hand hewn timber comes to us as is, and we scribe it to fit into a timber frame. Reclaimed antique timber frames are very beautiful, very special, and also very expensive.
Glulam beams are made from small sections of wood cut into strips and then glued or laminated together, creating a strong and stable wood product that can be used to stretch over great spans. It is a good options for clients who want to avoid the checking, the shakes or other natural variations and inconsistencies of natural timber. It is also a good choice for those who want long graceful curved beams.
Think Function First
So when deciding what wood species to choose, think about how you want your structure to function. Are you building a wide and long factory that needs arches that can stretch a great span or a smaller storage barn? You should also consider how you’d like your structure to look. How do you feel about checking, grain, color, and texture? Think about the big picture and what wood will best serve your needs.
When considering your wood species, you should also consider finishes, stains, and if you’d like your timber weathered or not. You have a lot of control over how the frame will look as you consider the many combinations and options to choose from. For example, rough sawn oak with a golden stain will look distinctly different from planed and chamfered Hemlock that has been weathered.
Do you have questions about wood species or need suggestions on what to chose? Submit a question on our ask the experts page or comment below!