Selecting the right materials for transitions and tie-ins is also important for achieving the desired performance and durability. Self-adhered membranes, while commonly specified for transitions, are not always the best choice. Self-adhered membranes are often used because of their flexibility; however, this flexibility also makes them susceptible to wrinkles, which can result in breaches at laps and terminations. Transition materials also must accommodate differential movement and provide thermal continuity.
Further, self-adhered membrane materials typically are not designed to bridge large gaps; continuous, rigid support is required. Thus, in some instances, a different flexible material, sheet metal, or sealant may be a more appropriate selection. Although the initial material costs for some alternate solutions may be higher, the costs to repair leaks can often far exceed these material cost premiums. Designers should be willing to consider different solutions and be open to considering new product solutions as technology advances. At the same time, designers should ensure materials are compatible and be vigorous in vetting new products to ensure they can meet performance requirements and stand the test of time.
Once the design is complete, designers turn it over to the contractor’s hands to bring the vision to life, but this does not mean the designer’s job is done. Turning the design into a functional system typically occurs during the shop drawing submittal process. It is critical for the designer to review shop drawings, material samples, and other submittals with the same principles followed through design. Do the submittals demonstrate a clear understanding of all control layers? Do they correctly show control layers within their systems and their connections with the adjacent systems? Do they show the adjacent systems accurately and are they consistent with drawings/construction by other trades? Is the system constructible? Is the material selection consistent with the original design? Often the submittal review process can be an iterative one, but it is an important step to complete thoughtfully prior to starting construction.
Mockups can be a critical “first test” for any project and are an important tool for achieving success. Mockup requirements should be clearly communicated in the project specifications, including the location of the test(s), the frequency, and whether they are to be constructed in a laboratory, onsite, and/or in situ. Mockups can save lots of headaches down the road by confirming the design is being followed, providing an established benchmark for construction, and, if needed, validating performance through testing before advancing with construction production.