One of these drivers is the choice of One way to control costs is to design a wood species. Choosing oak over mahog- hybrid frame that utilizes timber fram- any would dramatically reduce materials ing in the highly visibility areas and uses costs but may not achieve the desired look. stick framing or SIPS construction in the During the design process the team should remainder of the spaces. Often timber- review the characteristics of various species framed great rooms and front porches and tour several timber frames before se- are clad with and then married to SIPS lecting the species. construction. As discussed above, SIPS Another cost driver is the quality of provide structural support. Additionally, the wood, whether green (freshly felled), because of their design, they can be used kiln dried or reclaimed. Each of these can as structural building members, so whole markedly affect the price of the frame, with buildings can be constructed of SIPS. green wood typically the least expensive Another hybrid technique is to include and reclaimed wood the most expensive. A trusses in the design that are supported rule of thumb is that the drier the wood, by SIPS or stick-framed walls. It should the more stable, hence less checking and be recognized though that trusses can be tighter joints over time. These issues rarely structural or decorative, but the cost for have a structural impact on the frame and each will be about the same so they might are usually aesthetic choices. Requiring as well earn their keep. certified woods (Forest Stewardship Coun- In conclusion, timber framing is not only cil certified) sometimes affects price and one of the oldest construction techniques availability of certain species and should known to man, it is also among the most be reviewed during the design process. beautiful. That, coupled with its sustain- ABOVE: For a boathouse project in Cape May, NJ, that was designed in a collaboration between Hugh The finish on the timbers is yet another able nature, long life and design flexibility, Lofting Timber Framing, the owner and an architect, cost consideration. As discussed above, should make it the choice method for any- pegs were trimmed in preparation for raising the bent, each time the framer works with the tim- one contemplating a new building project. or end wall. BELOW: This custom carriage house, ber, it affects the cost of the frame. A designed by Hugh Lofting, features three bays, a loft and a lower-level storage area. It is crafted of Doug- rough-sawn frame is the simplest. Requir- Written by Amy Cornelius, LEED AP. las fir and finished with a pine tongue-and-groove ing S4S requires additional milling. Sand- ceiling, pine board-and-batten siding and hardwood Amy works with Hugh Lofting Timber Framing, ing and oiling, hand-hewn finishes, adzing flooring. Frame of Reference and sandblasting all provide distinct looks Inc., a LEED for Homes registered contractor. but require multiple handling of the tim- A simple design and a collaborative process are often hallmarks of a successful timber-framing project bers. Planning for the raising is an often imber framing is one of the oldest Designers’ desires for longer spans and Timber frames are manufactured in misunderstood cost driver in timber construction techniques known more complex joinery, coupled with in- a variety of ways. Most shops use some framing. Raising a timber frame takes an Tto man, but it remains one of the creased engineering review rigor, are driv- combination of power tools (chain mor- awful lot of space and this is something least understood in the marketplace. Evoc- ing timber framers to include more steel tise machines, etc.) and hand tools, such that is often lacking around construction ative pictures greet us from magazines and in their projects and to use a multitude of as chisels and mallets, for joint cleanup. sites. The best case scenario for the tim- coffee-table books, encouraging visions metal fastening systems. The steel can be Some specialized companies work in envi- ber framer is to have an area equal to the of grand rooms and entrances for homes, hidden within the frame or it can be vis- ronments that are powered by water wheels dimensions of an entire bent (end wall) churches, office buildings, barns and even ible, or expressed. Most often expressed and use only hand tools, others are slightly available on the ground to assemble the enhancements to our landscapes. The steel is seen as an integral part of the over- more automated and there are an increas- frame and ready it for raising. In this best problem arises after the vision: how do we all design of the structure. ing number of shops that employ CNC case there are no other walls existing on design, build and afford the dream? Many timber framers are also work- (computer numerical control) technology. the site, just a clear, level, squared deck. ing with manufactured timbers, including CNC technology allows computer design This is the easiest and least costly situ- Timber Framing Today glued-laminated and PSL (parallel-strand programs to communicate directly with ation, while raising the frame after three The traditional definition of timber fram- lumber) material. These timbers, manu- large robotic milling machines that then of the four walls are standing or trying to ing – “a frame constructed of heavy tim- factured from thin pieces, or “slices,” of cut the entire frame. Some companies cut raise trusses in a room where the roof has bers using mortise and tenon joinery that kiln-dried wood and then adhered under entire frames using CNC technology while already been placed makes for a more dif- is held together with wooden pegs” – is pressure, have high tensile strength and al- others cut repetitive components, leav- ficult and costly installation. expanding as the industry and design aes- low designers to achieve significant spans. ing the unique or more visible pieces to Access and site requirements also drive thetics evolve. They can also be quite beautiful. be hand-cut. Even in the fully automated costs. A steeply sloping lot or an inacces- sible driveway may preclude the use of a crane to raise the frame and add many la- As published in Period Homes Magazine n Volume 9, Number 5 n September 2008 bor hours for installation. frame shops, there is still a certain amount It is important to assemble the collab- Bringing this team in early lays a foun- openings and door and frame conflicts. By of hand work involved in cleaning up and orative design team early in the process, dation of good communication at the out- identifying pitfalls and opportunities early, finishing the frame, and sometimes in the preferably at the conceptual design stage, set of the project that flows throughout the client will save money and time on the more specialized compound joinery. and charge them with developing complete, the entire construction process. It allows frame that can be rolled into the project as solid plans before starting any construc- for tighter bidding, reduces cost overruns a whole. A Natural Choice tion. The team should at least include the from change orders and reduces total con- Pam Hinton is the executive director of In a timber frame, the structure of the client, the architect/designer, the builder, struction time. It also sends a message to the Timber Frame Business Council. “Our building is exposed inside the building. the timber framer, the HVAC contrac- the construction team that this is a project goal as an industry is to become more in- This is akin to inviting the outdoors inside, tor or consultant, the sustainable and/or that has been well thought out. This of- teractive with architects earlier in the pro- bringing the occupants closer to nature civil engineer (if any) and the landscape ten causes the construction team to take cess,” she says. “Our membership of expe- while providing almost all of the decora- architect. The plans they develop should greater care in their own work, resulting in rienced timber framers can help architects tion that the home or structure may ever include architectural, structural and fram- a better project all around. and their clients save money and make need. The interior spaces created are unen- ing, mechanical, storm water, electrical and Timber framing is a specialty business the projects more successful. Working as cumbered by structural walls, allowing for plumbing. and a timber framer should be included in a team, the timber framer can do what it an open floor plan that can be reconfigured Many times clients avoid MEP draw- the design process for a number of reasons. takes to express the architect’s vision in to the occupants’ needs and have a tangible ings to save costs, with the belief that the Most importantly, the lack of interior wood – a good collaboration will express feeling that exudes warmth, strength and general contractor and subcontractors walls and the prefabricated nature of the the intent of the design and maximize the security. will be able to develop the best mechani- frame present unique challenges for rout- potential of the materials used.” Timber framers work with many species cal program. When stick framing a struc- ing mechanical systems, and there is little of wood and many work with wood that is ture, this approach often results in cost wiggle room for changing the frame once it Cost Analyses local to their community. Each species has overruns. Given the prefabricated nature is fabricated. That is not to say that you are There is no doubt that timber framing its own characteristic look and personality. of timber framing and the limited inte- “stuck” with the framer for the duration is more expensive than stick framing, but Newly sawn or green oak is particularly per- rior walls, this approach quickly results of the project. The timber framer can be collaborative design and simple design help sonable when it is introduced to the heated This structure features Douglas fir solid king-post trusses with a glued-laminated bottom chord. The ceiling in problems with routing and installing brought to the project as a paid consultant to control costs. The collaborative design is Douglas fir tongue-and-groove decking that provides a warm feeling and adds to the structural integrity. environment. A framer once told me that his utilities. These problems frustrate the to address design issues and to develop a process helps to achieve the vision with a client complained of gunshots downstairs timber frame, leaving the timbers fully pact upon the project budget. Not that any construction team and often result in set of CAD drawings to be used in the bid- timber frame design that optimizes struc- in the night – it was the oak frame check- exposed. SIPS are manufactured off-site of these things are bad, but they should be additional costs for materials and labor. ding process. In this role, the timber fram- tural strength, total board-foot volume ing as it dried in the dry heat of the house. and can be pre-cut for windows and door recognized up front by the design team. Avoiding the MEP drawings may also er will identify potential factors that affect and manufacturing processes. During the Timber framers use a variety of species, in- penetrations, further lessening on-site con- Complexity also brings with it increased have long-term cost effects on operat- cost and buildability, including timber siz- design process, other cost drivers are de- cluding hardwoods (beech, birch, chestnut, struction waste and construction time. volumes of wood. Timber orders are mea- ing the building because design synergies ing, wood species and design complexities, termined and weighed against the overall elm, oaks, maple, cherry and hickory) and sured in board footage, where a board foot were not considered at the onset. and identify design problems such as stair project goals. softwoods (cedar, firs, hemlock, larch, pine, Design Basics equals a piece of wood that measures one spruce and tamarack). Simple, uncomplicated design does not in. by one ft. long by one ft. wide. Adding Timber framing is one of the most sus- mean boring. It does mean that keeping the hips, valleys and dormers to the frame in- tainable building methods available, sup- design simple, without complex roof sys- creases the total board footage that is pur- porting good forest management, low- tems, multiple dormers and various appur- chased for the project, and the loss factor carbon-input manufacturing processes and tenances, will help minimize costs while in each piece increases as steep angles are energy efficiency. Timber frames are typi- showcasing the timbers without clutter. cut into the timbers. In the case of dor- cally manufactured off-site and raised in a Timber framing is extremely labor in- mers, the total board footage of the roof matter of days. The prefabricated nature tensive. Even frames that have been cut increases and the pieces that are added to of the frame reduces construction time and on CNC machines often require hand the project are much more complex, adding site waste. Also, the choice of enclosure finishing. Every time the timber framer to materials and labor expense. systems for the frame can make it very en- works with the timber, the cost increases. ergy efficient and airtight. So, if you have a kiln-dried, S4S (smooth Collaborative Design A significant percentage of timber frames four sides) timber that is perfectly straight The collaborative design process is an itera- are enclosed with SIPS (structural insulated and the final design requires the same, the tive one that refines the design as the scope panels) that, when installed, form a blanket framer will work with it about three times: of the project evolves and is crucial to a of insulation around the frame that pro- assessing, laying-out and cutting. Each successful timber frame project. Collab- vides a significant R-value, very little ther- time the design becomes more complex – orative design is a communication inten- mal bridging and an airtight barrier. Much such as when the project utilizes antique sive process that has measurable benefits; like a sandwich, SIPS are constructed of wood that is by nature often out of square these may include, for example, identifying two outer layers of OSB (oriented strand and/or filled with nails, hand-hewn finish- synergies between building size, fenestra- board) that are filled with a thick layer of es, hand-carved embellishments and com- tion and mechanical equipment needs, or foam (polystyrene or polyurethane). The pound joinery – the time spent with the synergies between plantings, building ori- In re-creating the Pennsylvania barn, pains were taken to be authentic by using traditional joinery and reusing the oak nails or pegs while incorporating new light- SIPS are applied to the outside of the timber increases. This makes a direct im- entation and water use. ing technology. Tucked beneath the loft, the kitchen features an efficient layout with lots of workspace.