How to Avoid Common Errors in QCP Woodworking Project Inspection & Certification
There are various elements involved in project certification and in this article we explain how to avoid the most common errors and meet the requirements, smoothing the path to QCP project approval.
Obtaining your AWI-QCP woodworking certification brings with it a myriad of benefits, from being able to confidently estimate your work and manage projects effectively, to completing the job within all specifications. It also allows you to deliver compliance, consistency and quality to your clients.
Ensure Woodworking Project Certification by Avoiding These Mistakes
Both licensed AWI-QCP companies and non-licensed companies can learn how to avoid or solve the common mistakes outlined below in order to assure certification.
First, it’s important to recognize that for a project to pass inspection, it must comply with the minimum requirements of the standards. There are two major requirements you must meet on all projects before fabrication begins:
- Make sure the project is registered. This is a crucial part of certification as project registration is necessary in order for you to begin work on a project, and it’s often missed by the design professional. The project must be registered at least 14 days prior to commencing your work. If a project isn’t registered and you commence work, this is cause for suspension and possible revocation of certification.
- Comply with the minimum requirements in the AWS for shop drawings. Shop drawings are included in the initial QCP review, and deviations from the standards will result in non-compliance unless they are clearly noted and have been accepted by the design professional. Having this initial review is beneficial, as anything picked up at the drawing stage is easier to resolve than at the fabrication stage. You must make sure any changes to material or design are specifically identified in separate written documentation in the submittal package.
20 Common Woodworking Project Certification Errors to Look Out For
We’re specifically highlighting these twenty errors in woodworking project certification as our QCP inspectors commonly see them in the fabrication and installation of projects. There is more detail about the QCP standards and requirements for each of these points in this table, and you can also watch our webinar.
- Fasteners for captured cabinet backs: Cabinet backs which are plowed or dadoed into the cabinet body must be securely nailed or stapled to the case body at a maximum of four inches on center.
- Cabinet anchoring to structural walls: At least two fasteners at both the top and the bottom of the cabinet are required. They should be spaced no more than 16 inches on center, and should all be located both horizontally and vertically within three inches of the outside surface of the end panels and/or top and bottom panels.
- Door and/or drawer alignment, flushness and gaps: A project with any amount of casework is likely going to require final adjustment of doors and drawer fronts after installation. Face edges, faces, and gaps need to be within certain AWS (Architectural Woodwork Standard) tolerances, but please note that these standards look for an overall impression of first-class workmanship rather than absolute perfection.
- Spacing of case assembly wood dowels: The dowel must meet certain minimum size requirements and must be glued with a minimum of two dowels per joint.
- Sealing of sink cut-outs: We typically find that if the sealing of one sink cut-out has been missed, they have all been missed. Cut-outs must be sealed with a water-resistant sealer before trim or sink rims are installed. The project specifications should detail who is responsible for the sealing of sink cut-outs, whether that’s the woodworker or the plumber.
- Cladding for p-lam doors and drawer fronts: Cladding on the inside faces of p-lam doors and applied drawer fronts should be the same thickness as the cladding on the outside face (this is a requirement for custom grade), and should be the same color and pattern as the outside face (for premium grade).
- Wall scribe maximum units: There must be closure at all visible voids, which cannot exceed one to one-and-a-half inches in width.
- Edgebanding: This applies for example to cabinet bodies and doors. Edgebanding specifications are easy to miss from the specifications but must be included. Edgebanding happens early on in a project and can be costly to correct the errors if it’s gone too far.
- Closure provision is required at all voids: Voids between a structural wall and a wall cabinet must be closed not only at the cabinet front but also at its top and underside.
- Wall cabinet ends: If wall cabinet ends extend below the bottom of the wall cabinet, the interior exposed surfaces of the ends must be of a finish compatible with (in custom grade), or identical to (in premium grade) the cabinet’s other exposed surfaces, for example, the cabinet doors.
- Wall cabinet top edges: Edgebanding on the top edges of wall cabinets that are eighty or more inches above the floor, open above and not visible may be applied or omitted at the discretion of the manufacturer. The banding itself can be the woodworker’s choice as per AWI Interpretations.
- Anchor strip fastening: When the back panels are sandwiched between anchor strips and the bottom panel, top stretchers are to be screwed (not stapled) to the case body at a maximum of four inches on center.
- Anchorage screws: Anchorage screws must have surface-bearing heads. A surface-bearing head is defined as a screw with a homogeneous head that has a flat bottom surface at least two times the diameter of the screw shaft. Screws and washers are not considered surface-bearing heads.
- Base cabinet fastenings to loose base: Base cabinets which aren’t mechanically fastened must be attached to the bottom with flathead screws, set flush or slightly recessed to prevent movement. There is no standard for spacing or the number of screws used.
- Drawer front to sub-front fastener spacing: Drawer fronts must be screwed to the drawer sub-front with a minimum of two screws at each end. These screws must be a maximum of one-and-a-half inches from the inside corner of the drawer box, and a maximum of 12 inches on center. These screws can also be used for drawer pulls to meet the on-center requirement.
- Open cabinet anchorage fastener cover caps: On any exposed interior surface, cover caps of a compatible color with the interior are required. This can be a problem with surface head screws, especially when the architect doesn’t want them to be covered or there isn’t a compatible cover for the screw that’s been specified. In those situations, QCP will provide suggestions of compatible covers. You could also countersink the head, but in this case, you will need to ensure that structural integrity is maintained.
- Drawer boxes must be within two inches from the cabinet back: Drawers (including trays and sliding bins) must fit front to back, less a maximum two inches of interior cabinet depth. If additional space is required for wiring or if the cabinet is large and drawer slides aren’t available in the required length, QCP will accept this.
- French or locking cleats used for installation of wall cabinets: An interlocking hanging cleat may be used for wall cabinet anchorage only if it has been independently tested to show compliance to the Wall Cabinet Structural Integrity Test. If it has been tested, a copy of the report must be provided to QCP in order to accept it as a method of anchorage.
- Incorrect adjustable shelf thickness: This error mainly occurs in school or hospital projects, where shelves require a higher load capacity of 50lbs than in commercial projects (40lbs). The load capacity and the structure of the shelf determines the requirements for the thickness of the shelf.
- Incorrectly sized anchorage fasteners: Anchorage fasteners must be a minimum of three inches long and a number 10 diameter.
All errors must be corrected prior to QCP project certification, but there is always the opportunity to appeal a decision the inspectors make.
And for a bonus point…look out for wood veneer wall panelling. There are a lot of moving parts with veneer specification and it’s regularly a significant issue in QCP certified projects.