Old Versus New: Does Old Growth Wood Really Make a Difference?
Lumber today is not the same as it was 100 years ago. Due to the high demand for lumber, sturdier old growth trees experienced over-harvesting, which drove forests to near extinction. Lumber farms, where trees grow at a much faster rate but have less density, have become the primary source of wood for construction. As a result, today’s 2×4 is not equal to the 2×4 from 100 years ago.
When renovating an older home or building, in most cases you can’t simply replace the existing wood with the same size of new growth wood and still maintain structural integrity. An experienced Structural Engineer provides expert knowledge to determine the materials required to ensure any alterations meet today’s Building Codes.
Old Growth Wood
Old growth wood is wood grown naturally in a virgin forest and not a lumber farm. To classify as old growth wood, the wood must contain heartwood which forms after at least 50 years of growth.
Old growth wood is far superior to new growth wood. Comparatively, new growth wood reaches maturity in 10 to 20 years. The goal with new wood is to grow the wood as quickly as possible. For construction, you now need larger wood sizes to achieve the same level of structural soundness due to the lower density.
The biggest benefit of old growth wood is the higher density. Older trees that grow naturally develop tighter growth rings which creates more robust lumber. The tighter growth rings allow the wood to have greater capacities. Also, old growth wood has natural rot-resistant properties and more firmness, meaning it doesn’t shrink and expand as much as new growth wood.
How to Create Structural Soundness with New Growth Wood
For renovation projects today, new growth wood is likely your only option. With the right engineered design, you can achieve the structural support you need with new wood. Southern Yellow Pine is the most common material for support beams and joists. Also, Southern Yellow Pine offers a good option when renovating older homes due to its high strength to weight ratio. Even so, the National Design Standards updated their wood strength back in 2013 for Southern Yellow Pine by decreasing the rating by 30%.
Despite this reduction, wood remains a viable building resource. Wood works well for both new construction and renovations. The key is working with the right professionals to ensure your project reaches the correct standards for structural soundness. With renovations, you must also consider how any removed walls or additional weight will impact the support structure. Partner with a Structural Engineer before you begin the renovation project to determine the best plan to maintain and improve the structural soundness throughout the project.
Partner with a Structural Engineer
At Russell Rowland, we love to work on renovation projects for older homes and buildings. We appreciate the craftsmanship and history, and work to preserve the integrity of the property. As such, we provide the experience and knowledge necessary to build structurally sound projects, including the right type and volume of wood.
Contact Russell Rowland to discuss how we can help with your renovation project