FAQs

or…What to Expect When You’re Expecting a Timber Frame

The process of creating a timber frame is important, regardless of how well the finished product turns out—just ask someone who endured a terrible process to obtain their timber frame.

There is neither a shortcut, nor any secret to designing a timber frame. But whether good or bad, every timber frame company has a process. This is ours.

It starts with a dream: a spark that inspires a homeowner or a business owner to build something.

We’ve been doing this long enough to know that we’re not the right fit for every project that comes along. We half-jokingly call this first meeting the “dating phase.” There’s an understood agreement that this meeting is about learning about one another—how we both like to work, what makes us tick, our expectations. We ask you questions, and we answer your questions. (Here are some good ones: How to Interview a Timber Frame Company). Afterward, if either of us doesn’t think the partnership is a good fit, we say so, parting ways amicably and with no hard feelings—and with no expectation of a second date.

But if, on the other hand, we both agree the match has potential, the discussion turns to taking the budding relationship to the next level. The rosy flush of romance may fade considerably at this point because we (Carolina Timberworks) will bring up the subject of money on only the second date. Tacky, right? To make matters worse, we’ll throw in questions about timing. Uncomfortable though it may be, this refreshingly open communication results in saving both of us a lot of time, money, and frustration. After all, you probably don’t want to spend months waiting (and paying) for a timber frame design, that when finally priced, turns out not to fit your budget.

At this point, it’s time to talk commitment. You’re about to “marry” a timber framer—something your mother probably warned you about. (Okay, maybe not. But bet you didn’t know that timber framers’ mothers warn them about marrying the wrong clients!) Doubt and fear make their appearances. But this is why prenuptial agreements (contracts) were invented. Really good timber frame contracts are all about reducing future disagreements and problems by carefully defining what success looks like. The best ones are easy to understand, fair to both parties, contain good drawings, and are typically fairly lengthy. You wouldn’t sign a one­-page prenuptial agreement, would you?

Now something weird happens in the relationship: At this point your honeymoon begins, but your timber framer has to go to work. While you’re basking in the sense of accomplishment that comes from knowing that you’ve conceived the latest addition to your family, your timber framer will be spending a great many days/evenings/weekends in front of a monitor, painstakingly working out a whole lot of details.

It’s three weeks into your honeymoon. You feel a bit guilty about emailing your timber framer that breathtaking photograph of your view of the Matterhorn from the Mont Cervin hotel in Zermatt, Switzerland. Hard at work, your timber frame spouse replies rather distractedly and with some frustration: “The engineer just called. He woke up in the middle of the night worried about…” The words every timber framer dreads. The “separate honeymoon” phase continues.

If children were produced like timber frames, sometime prior to birth, you’d receive, with a certain amount of fanfare, an amazingly complex set of drawings from the doctor with every measurement of your baby you could want—and quite a few more—including views from every possible direction or angle. To your dismay, you realize the timber frame shop drawings are pretty complex, and out of your realm of knowledge of design. It’s at this point your architect, builder, or contractor steps in with their trusty red pen, marking up the drawings and suggesting changes. Back to the timber frame shop the drawings go to the love of your life (your timber framer), and in due course, a revised set of drawings arrives in your inbox. Upon consultation with your architect or builder, one of you will sign off on the shop drawings, thereby unleashing the timber frame dogs of war (okay, that doesn’t really work, but always wanted to work that phrase in somewhere).

The timber procurement process is a bit like gestating a baby: there are times where it seems like not much is happening. This can be a blessing, for your often hyper-focused timber frame mate appears to relax a bit, and even suggests a meeting. The subject? What to Expect When You’re Expecting a Timber Frame— The Next Steps.

The first thing most people do when walking into a timber frame shop is to pause, smile, and comment how good it smells. Just like babies, freshly cut timber smells good! And just as babies symbolize new life, the beginning of a new job in a timber frame shop always feels like a fresh new start. Some timber frame parents just can’t wait for a peek at their new child, and visit the shop for an early “reveal”. Others, preferring to be surprised, are willing to wait just a few more weeks…

Suddenly, after months and months of slowness, things start to happen—fast. You’ll know you’re entering the final phase when your timber frame spouse’s extended family starts arriving in their pickups to raise your timber frame. You knew the “relatives” (our crew) was part of the deal, but you never expected this many beards, that they’d be this hungry, or that they’d be this nice!

Here’s another family secret: Timber framers don’t really like clothes. Don’t believe me? Watch carefully. Once the timber frame is standing, the crew’s phones will come out. And if you’re lucky you’ll catch a glimpse of each member of the crew, your extended family now, casting one last glance at their baby just before they depart. And if you could read their thoughts, you’d know they think the baby will never look more beautiful than at this moment—completely naked, without a stitch of siding, roofing, or other finishing touch.

Did you know that mid-rise and high-rise buildings can now be built out of wood? An emerging building typology called mass timber is quickly gaining momentum as a viable alternative to traditional construction methods. Instead of using steel, masonry and concrete to construct these buildings, architects and engineers are using wood – allowing for sustainable construction, warmer aesthetics and remarkable improvements in construction efficiency. 

Why is mass timber so revolutionary? What’s the big deal?

Because of the potential to significantly reduce carbon emissions in the atmosphere, and reverse climate change. These benefits are plausible due to two big facts about construction. First, carbon emissions from the building industry account for approximately 40 percent of global carbon emissions. Second, the manufacture of concrete and steel together contribute about 10 percent of current global carbon emissions. Andrew Ruff of Connecticut-based Gray Organschi Architecture explains, “If you look 30 years down the road to 2050, we’re projected to have 2.3 billion new urban dwellers. That is a huge amount of construction. Every day that goes by that we don’t convert from mineral-based extractive construction techniques to carbon sequestering building systems, we tend to dig ourselves further in a hole” (Yale Environment 360: As Mass Timber Takes Off, How Green is this New Building Material?, April 2019).

Conversely, using wood in building actually removes carbon dioxide (CO₂₎ from the atmosphere. Scientists refer to the process as carbon sequestration, but we like to think of wood as a carbon sponge. A tree is nature’s solar-powered CO₂ storage machine, until the day it dies. Then, if left to rot–whether in a forest or landfill, or the wood burned–the sponge is wrung out and the CO₂ returned to the atmosphere.

Here’s where it gets interesting: take that same wood and keep it dry, as part of a building in the form of mass timber–whether a timber frame, glulam trusses, or cross-laminated timber walls and floors–and it will last indefinitely. Hundreds of years. Longer than concrete. 

Mass timber is part of the solution to our climate change problem.

But first, what is mass timber?

The term mass timber might be confusing to some of us. First things first: the term mass timber refers to a building typology – a way in which the building itself is made of large, solid wood structural pieces for wall, floor, and roof construction.

As large solid pieces of timber become more expensive to source, mass timber is being fabricated using many smaller individual pieces of wood – literally tons of wood go into the making of these manufactured structural pieces. With mass timber, the large engineered wood structures of a building are made entirely of wood – usually the beams, columns, arches, floors and roofs – and fabricated offsite to engineered specifications. 

Hence, the term mass refers to the large, solid components, and the term timber refers to a solid or manufactured wood product. 

One more thing that might help – the criterion to define a mass timber building is as follows: If the primary load-bearing structure is made of either engineered or solid wood, we can call it a mass-timber building. If the building uses mass timber as an accent and not as a primary structural element, then it is not mass timber. (Construction Dive: Mass Timber 101: Understanding the Emerging Building, May 2017)

So, what are the most common timber products being used today?

Sawn Solid Timber (timber framing, post & beam construction)

Traditional timber framing is the more than 2,000 year old building method (some would argue it’s an art) of connecting two or more pieces of timber using wood-to-wood joinery.  Prior to the discovery of metal, this is how timber posts and beams were connected to frame the homes, barns, and businesses our ancestors lived and worked in.  Held together without nails, bolts, or metal connectors–timber frames tend to withstand the test of time–many with a lifespan measured in centuries instead of decades.

What is a timber frame? learn more

What’s the difference between timber frame and post and beam construction? learn more

Glue-laminated Timber (glulam)

Glued laminated timber (glulam) is an engineered wood product made by laminating smaller pieces of solid lumber together with moisture-resistant adhesives into a single, usually large and very strong, structural member. These large structural members are used to create vertical columns, horizontal beams and floors, as well as curved arches. Glulam technology allows architects to design bold curved shapes, in a range of wood species and appearances. And because of their strength and stiffness, Glulam timbers can be used to create beams and arches that span large distances – up to 300 feet – without using supporting columns. 

Cross-laminated Timber (CLT) 

CLT was first developed in Germany and Austria in the early 1990s in response to an increasing shortage of old-growth timber. A CLT is a large, prefabricated, engineered solid-wood panel commonly used for long spans in walls, floors, and roofs. Finished panels are typically 2 to 10 feet wide, with lengths up to 70 feet and thicknesses up to 20 inches. They are light-weight and very strong, with superior acoustic, fire, seismic, and thermal performance. CLT’s are manufactured by combining layers of lumber boards which are stacked in alternating directions, then bonded with structural adhesives, and finally pressed together to form a solid rectangular panel. CLT’s are fast and easy to install, and because they are engineered and fabricated offsite, do not generate any waste at the jobsite. As an alternative to traditional concrete and steel, CLT’s are eco-friendly, offer increased design flexibility, provide better thermal insulation, and lower construction costs due to prefabrication. Did we mention that they are beautiful to look at?

Nail-laminated Timber (NLT)

Nail-laminated timber (NLT). NLT has been around for more than a century, and used to be known as heavy timber or mill decking. To create an NLT, you simply stack layers of dimensional lumber on end and fasten them together with nails or screws. NLT is commonly used in floors and roofs as a valid substitute for concrete slabs and steel decking, with the added benefit of creating a unique, exposed wood aesthetic. Whereas CLT is a newer technology in North America, and not always fully understood by building inspectors, NLT works well for simple spans – it’s also less expensive, and is firmly accepted in the building codes. The downside? Your saw is not going to be happy if you have to cut openings in NLT panels.

Dowel-laminated Timber (DLT) (no glue, no nails)

Dowel-laminated timber (DLT). The same as NLT, except instead of using glue or nails to fasten the lumber, wooden dowels are used. A major benefit is the lack of off-gassing from adhesives.

So why use Mass Timber?

Besides offering a low-carbon alternative to traditional building technology, the exposed wood interiors in mass timber buildings are warmer than other materials and far more aesthetically pleasing that concrete and steel. People love them, and literally want to hug the wooden interiors. This is because there’s still no other building material quite as warm and welcoming as wood. Besides the calming psychological effects of living in a wooden building, there are the physiological benefits: the buildings actually smell of wood, usually pine and spruce. 

One last reason might convince you to consider CLT – the business case – developers and builders using mass timber are getting a lot of attention. 

If you are getting really inspired about wood buildings, we recommend watching Michael Green’s TedTalk on “Why we should build wooden skyscrapers”

Carolina Timberworks is proud to design, fabricate, and install timber framing, glulams, and CLT panels anywhere in the United States.

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Curious about how buildings can be part of the solution to climate change? Read our review of Bruce King’s book, The New Carbon Architecture.

At first glance, timber frame and post and beam structures may appear similar. After all, both rely on heavy timber to create open spaces with exposed beams. Yet the difference between timber frame and post and beam construction is the way the individual parts are connected: 

• Timber framing uses wood joinery and rarely uses steel parts
• Post and beam structures use metal fasteners and connectors

What Is Post and Beam Construction?

Post and Beam Construction Essentials

Post and beam structures are built with vertical posts and horizontal beams. Metal brackets and steel plates join the timbers and hold the structure together, but they aren’t always visible. In some cases, they’re decorative, but in other cases, they’re structural and placed out of sight.

Pros of Post and Beam Construction

Post and beam building generally has lower skilled labor costs than timber frame construction. Although post and beam structures require plenty of labor, they tend to be less complex in engineering, construction, and fabrication. Additionally, decorative or structural metal plates can add a specific style to a post and beam structure.

Cons of Post and Beam Construction

Moisture can condense on steel surfaces, causing the steel to rust and the surrounding wood to decay. Depending on the complexity of the metal plates, post and beam construction material costs can be more expensive than traditional timber framing. Dissimilar materials (metal and wood) also tend to work loose over time.

What Is Timber Frame Construction?

Timber Frame Construction Essentials

Timber frame construction relies on wood-to-wood joinery—so there’s no need for metal brackets. The timber frame is almost always exposed, creating a space that’s’ simultaneously open and cozy.

Pros of Timber Frame Construction

Usually (but not always), timber frames are more attractive, elegant, and expensive than post and beam structures. Traditional wood-to-wood joinery, if kept dry, can endure for centuries. In addition, traditional wood joinery is somewhat elastic–in other words, it can deflect and give a little under loads. This is one reason that certain examples of Japanese architecture have survived for over a thousand years–despite the destructive earthquakes that occur several times each century.

Cons of Timber Frame Construction

Timber framing has a higher cost of skilled labor to design, engineer, and fabricate traditional joinery. Some structures increase timber cost when timber sizes increase, which may occur during engineering to accommodate joinery.

Post and Beam Construction vs. Timber Frame Construction

What Do Both Construction Methods Have in Common?

Ultimately, timber frame and post and beam structures have a similar visual style. Both tend to create open spaces with exposed beams and a natural elegance. That’s because both types of construction use heavy timbers rather than 2x4s.

How Joinery Makes a Difference in Construction Methods

Some timber framers believe that wood should be the only component in a true timber frame structure. When it comes to timber frame construction, mortise and tenon joinery brings everything together—both aesthetically and structurally.

In contrast, post and beam construction uses metal plates and bolts. While that may not seem like a big difference, some would argue that this method isn’t truly timber framing.

Curious which is the right choice for your project? Give us a call at 828-266-9663 or send us an email.

We’re often asked, “What is the best wood for timber framing?” Although it’s estimated that 60% of timber frames in North America are built from Douglas fir, there are other timber frame wood species that may work as well, or better, for your building project.

So, here in one place, is exactly how to select a timber species from the most common woods used in timber framing. Perhaps as important, you’ll learn how to specify the other important wood characteristics for a timber frame — things like timber grade, moisture content, heart content, and surface texture.

Common Timber Frame Abbreviations

• AD: air-dried
• BH: boxed heart
• FOHC: Free of Heart Center
• Glulam: glued laminated timber
• GRN: green (freshly cut, wet)
• HT: heat-treated (reclaimed wood is sometimes heat-treated to kill bugs)
• KD: kiln-dried (when timber is dried in a conventional kiln, only the outer inch or so is dried)
• PAD: partly air-dried
• PT: pressure-treated (with chemicals to resist decay)
• RFKD: radio frequency kiln dried (dry to the core, but only applicable to Douglas fir
• S4S: surfaced four sides
• S-Dry: surface dry
• TAD: thoroughly air-dried

Characteristics of Common Timber Frame Wood Species

For each of the common woods used in timber framing below, we’ve noted the characteristics, decay resistance, and the relative cost ($ less costly, $$ average, $$$ more costly). Some of the information below is adapted from the USDA Forest Service’s Forest Products Laboratory book: Wood Handbook–Wood as an Engineering Material.

Bald Cypress (Taxodium distichum)

Also known as southern cypress, tidewater red cypress, yellow cypress (inland), and white cypress. Southern US softwood; moderately heavy, moderately strong, and moderately hard. Old-growth is resistant or very resistant to decay, but no longer readily available. Second growth is moderately resistant to decay. Sapwood is narrow and white-colored. Heartwood color varies from light yellowish to reddish-brown color. Shrinkage is moderately low but somewhat higher than the cedars. Difficult to obtain longer than 20′.  $$

Port Orford Cedar  (Chamaecyparis lawsoniana)

Straight-grained, fragrant, and durable. A softwood that grows along the Pacific Coast from Coos Bay, Oregon, southward to California in a narrow band less than 40 miles wide. Fine texture, generally straight-grained, with a pleasant spicy odor (it reminds us of ginger). Moderately lightweight, stiff, moderately strong, and hard. The heartwood is highly resistant to decay. Moderate shrinkage with little tendency to warp. Prized by Japanese temple builders as it resembles Japan’s sacred and rare, Hinoki Cedar.  $$

Western Red Cedar (Thujaplicata)

Straight grained, low shrinkage, durable. A softwood that grows in the Pacific Northwest and along the Pacific Coast to Alaska. The heartwood is reddish or pinkish brown to dull brown, and the sapwood is nearly white. Narrow, and usually less than 1″ wide. Very low shrinkage, lightweight, moderately soft, low in strength. The heartwood is very resistant to decay because the chemical substance Thujaplicin, found in mature western red cedar trees, is a natural fungicide.  $$$

Eastern White Pine (Pinus strobus)

The “moderate” timber: moderately soft, moderately low in strength, moderately durable, and moderate shrinkage. A softwood that grows from Maine to northern Georgia and in the Great Lake States. Challenging to obtain graded for structural timber framing. Creamy white or pale straw to light reddish-brown. Darkens with time to a light caramel color, then after many years to a deep rich golden tan. Stains well.  $

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