In the first part of the Primer for Wall Panels, we discussed the fundamentals of wall panel production and how they may figure into your wood component business. In summary, we asked the reader to remember that wall panels were built for decades with little more than a blueprint, carpenter’s square, a hand saw, and a “can do” attitude. In closing part one, we stressed that before you invest in wall panel production you should consider some of our basic criteria and ground rules:
- Rule #1: Your most likely prospect for manufactured wall panels is the same person/company that is directly responsible for framing labor. In other words, the person who signs the P.O. for wall panels needs to be the same person that “writes” the check for framing labor, as they are the one who benefits directly from field-labor savings.
- Rule #2: From our experience we believe that wall panel equipment is easy to over-invest in.
- Rule #3: All you must have to build wall panels is a flat surface such as a floor deck on a job site (aside from a saw, lumber, and nails of course).
- Rule #4: Equipment purchases should be based on matters of productivity and quality. Let your combined experience be your guide as to what is truly sensible.
- Rule #5: Your investment in equipment is largely determined by what your daily or weekly linear feet of wall production objectives are today and over the next 3 to 5 years.
- Rule #6: The very best equipment for your specific needs can be some combination of new, used, and even “home” made.
As promised, here is Part Two of the Primer for Wall Panels with the the answer to the question; “What are the fundamental elements of equipment necessary to build wall panels?”
- Product Design: Of course manufacturing any building component begins with accurate design in your shop. The plant can only build what is designed so it is critical that the designs match the intent of the construction documents provided by the building contractor or architect. It is also critical that the panels are designed to fall within the limits of the plant’s capabilities. For example, if you have a framing table that allows for up to ten foot high walls, a 12 foot wall will need to be built elsewhere or field-framed.
Wall panel layout is generally done using the following methods:
Manual design of panels: For years people have hand drawn wall panels. The most efficient way to manually design wall panels is to mark up the blueprints based on the preferred panel lengths, then draw a separate bottom plate drawing showing the stud and opening placements with both heights and horizontal dimensions. For a house or two a week, this may be fine. The drawback is using a blueprint that has a dimensional error. Your wall panels would be inaccurate if you only use the graphics without double-checking the written dimensions.
Design software: There are a number of wall panel design software programs available to you. If you are a wood truss shop, it is likely that your nail-plate supplier has a wall panel module available*. Other wall design software is available from independent sources. Some offer a one-time purchase price and others charge a monthly fee. A big advantage of design software is its ability to import CAD drawings from truss design layouts, architects, and builders to create accurate dimensioning and cutting. The ability to copy, flip, and paste data makes repetitive designs easier with software than a manual layout (design) approach.
* (Keep in mind that wall software from your nail-plate supplier generally comes at an additional fee. Why? Well, the “currency” that pays for design software is their proprietary nail or connector plate which are rarely used in wall panel production. In a few words, you must pay to play.)
So you believe you have a good design to send to your builders, now what? Well here are the fundamental areas that will likely require an equipment investment:
- Cutting and Marking – This is where the physical accuracy of your finished wall panels is established; it is essential that you are accurately cutting plate material and correctly marking stud, sub-component, and opening locations for the rest of your manufacturing process to be accurate. In addition you will be cutting all of the other dimensional lumber elements of a wall panel (blocking, etc.), and keep in mind that better than 95% of your cutting will be 90°, right-angle cuts. Solutions in new equipment will run between $10,000 and $55,000 for manual/semi automatic cutting and from $125,000 to $300,000 for full automation.
- Sub-Component Assembly – These elements include stringers, trimmers, ladder panels, corners, T’s, and the like to be used in wall frame and rough opening assembly. Again, in more than 95% of these assemblies you will be joining dimensional lumber at 90° angles. Solutions run between $100 for a wood bench to $25,000+ for systems with pneumatic clamping and squaring nailers.
- Rough Opening Assembly – These elements include window and door (interior and exterior) openings that are pre-assembled and “dropped” into to the wall frame during the framing process. Rough openings generally utilize some sub-components such as headers and trimmers for doorframes. They are sometimes referred to as sub-component openings. Generally built “just in time” on the framer, squaring-table, or on a manual framing surface.
- Framing – This is where both exterior and interior walls are built with a combination of top and bottom plates, studs, sub-components, and rough openings. At this point in the assembly process square, tight joints are essential prior to the joining of the members by fasteners (nails). For interior walls this is typically the end of the line. Solutions run the spectrum from a home made framing table ($500), to OEM built electric/pneumatic tables $35,000+, to fully automated machines at $200,000+.
- Sheathing – Here is where exterior walls that require sheathing are finished. Sheathing material in the form of various materials (OSB “plywood”, foam-core board, Styrofoam™, DensGlass®, etc.) is applied to the completed wall frame at this location. The sheathing material is either pre-cut or applied in sheets then routed for application around openings, and usually applied with nails or staples at code-specified intervals. The sheathing process may be accomplished at a single location or in two stages: squaring, applying, and “tacking” the sheathing followed by squaring and fully fastening the sheathing to the elements of the frame. Either way keep in mind this process is always the primary “bottle-neck” or time-consuming task in a manufactured wall panel operation. OEM solutions may run from $75,000 to $125,000+, but in any regard this is one area where you should not “wing it”. An investment in equipment to be accurate and productive is definitely warranted.
- Stacking – This is where your product is prepared for shipment and orderly use by the field framing crew. Neat, organized, secure bundles are the “name of the game” and there are several ways to accomplish this, largely dependent on the physical layout of your facility. Stacking order is generally a function of your design software as most of the current wall software has a stacking function that generally determines the “build” order. Sometimes customers will ask for a specific stacking order. Solutions may include a panel lift (think ice tongs), hoist (electric or pneumatic), and a frame to support the lifting process.
- Delivery – There are several ways for wall panels to be delivered to and unloaded at the job-site. The “right” way will be determined by many factors largely influenced by the expectations of your consumer. In many locations the combination of an all-terrain forklift and a flatbed trailer seems to work best. In other areas, panels must be delivered and set with a crane on site for you to be competitive in the marketplace.
- Personnel – As mentioned you need solid design software which is available from a variety of suppliers. We believe it is also important that you find some design and production personnel that are experienced in framing wood structures to help you deliver a “user-friendly” product to the field framing crews. Regardless of your current business nature there in no substitute for staff with wood framing experience, and a first-hand knowledge of framing practices and preferences in you market. It is crucial that you do your “homework” in this area.
Our objective in this two-part series was to help you determine what strategy you should have relative to the growing market segment that manufactured wall panels represent. If your current status includes building or planning to build wall panels, we hope that we have helped you to identify the fundamental elements of wall panel production. There would of course be more to discuss to plan a manufacturing operation, (such as building size and material flow!) but that is best left to individual consultation with knowledgeable, SBCA affiliated industry professionals.
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