Facilities (Campus Spaces)

Who Owns Your Building Envelope?

building envelope: parking structure

PHOTO COURTESY OF IWR NORTH AMERICA

Building envelope systems include all the elements of the outer shell of a structure necessary to maintain a dry, heated or cooled indoor environment and facilitate its climate control. The owner of the building façade typically hires a general contractor to assemble a team of subcontractors who will furnish and install individual systems that will ultimately make up the building envelope. Issues can arise with the functionality and performance of the building envelope at various stages of the process, from pre-construction design through execution of the warranty.

Design

The design-assist approach is a project delivery method in which the construction team is engaged by the building owner to collaborate with the design team earlier in the process. This concerted teamwork approach streamlines the design process and allows for primary parties to be involved from start to finish, enabling each participant to ask questions and make recommendations along the way. Coordination of the design details is essential to achieving a façade that is highly efficient and performs as expected. Alternatively, in the traditional design-bid-build delivery method, it is often too late or too costly for the building owner to address an issue or concern with the design.

In a design-assist approach, one of the most important elements is determining who is accountable for each of the responsibilities necessary in the design process. Contractually this is very important as everyone on the team plays a key role, and this can lead to confusion on where the professional obligations fall. Consequently, it is imperative that the roles and responsibilities of each party be clearly identified at the beginning of the design phase in order to reduce waste and establish accountability. Without the clear identification of the roles and responsibilities, ambiguity can create issues of ownership of the professional liability.

building envelope: exterior window wall

PHOTO COURTESY OF IWR NORTH AMERICA

In addition to ownership of design responsibility, it is crucial to have a clear signal of when the design phase has ended and the construction phase begins. If there is not clear identification, the project schedule is in jeopardy, often causing a delay in completion.

Typically, multiple companies are hired to enclose the building, each bearing responsibility for different systems that will ultimately need to work in unison. Unfortunately, if several subcontractors perform the work in segments during the design phase, the tendency moves toward only concentrating on factors specific to their own detailing. This will lead to failure of true analysis of the adjacent systems and their resulting compatibility with the next subcontractor. A design-assist approach is arguably one of the best ways to achieve true collaboration on both the elements of design and installation of the building envelope system.

Transitions

Transitions between each system of the building envelope require careful management to avoid potential moisture and air infiltration issues. Subcontractors often detail up to the adjacent system with a generic description of “by others.” This approach becomes problematic when other subcontractors are following suit and drawing their system up to the same transition point and also labeling it “by others.” The individual systems are typically submitted as separate proposals to the general contractor, and the lack of detail at the area of transition will be the weakest link of the design. As a result of the deficiency of coordination at the transition between systems, the exterior wall is now susceptible to permitting the infiltration of both air and water.

The general contractor or construction manager is typically responsible for coordination of these transitions within the building envelope. The general contractor must decide who goes first, who is responsible for the scope of work at each transition and if there are any warranty gaps. Proper detailing and review of the systems and materials with focus at each transition is the most effective plan of quality control during the construction process.

One option to reduce performance conflict at transition areas is to hire a subcontractor that handles the entire building enclosure. Companies are starting to employ a building enclosure partner philosophy by widening their capabilities in order to handle the entire building envelope scope. Having an all-in-one approach eliminates the common issues of lack of communication and poor coordination that arise when using multiple subcontractors.

Schedule

Construction schedules set at the beginning of the process are seldom right. There are factors, such as weather, that impact a project schedule and are out of anyone’s control. However, one of the main issues that frequently causes delay is that multiple companies are involved in the construction process. Each company requires direction and management, increasing the possibility of a modified project schedule.

To decrease the chances of a late schedule, it is important to drive each design phase conversation in the direction of cost, performance and schedule, leaving each meeting with clear direction. Alternatively, hiring one building enclosure contractor in lieu of multiple subcontractors can help eliminate the time necessary to coordinate the vast amount of details required and keep a project schedule on time.

building envelope

PHOTO COURTESY OF IWR NORTH AMERICA

MIND THE GAP. Your building envelope protects what is inside your building from what is outside; in particular, moisture. Because all of the possible moisture-related issues in new construction are not always immediately apparent to an architect, the entire design and construction team — or teams — must tackle design issues relating to the architectural aspects of building. Therefore, it is vital that there be no gaps in knowledge, intent or responsibility as the building envelope is assembled in order for the result to be a secure, functioning facility.

Coordination

Trade coordination is required when multiple subcontractors have been hired to furnish and install the complete building envelope. The process of trade coordination is important because it allows questions presented by the ownership and design team to be addressed, ensures that the full scope of work is captured and the overall design is understood.

Trade coordination meetings are challenging because they require all parties to come together for review. It can be difficult to organize a time and place in which everyone is available. This challenge is emphasized when a project schedule is disrupted and meetings must be pushed back or cancelled. In order to ensure that a project is on time, on budget and performs well, these coordination meetings are paramount.

In addition to timing issues, responsibility for gaps in the project’s scope of work is often met with resistance because each subcontractor is working to mitigate risk for the benefit of his or her own company. These issues could be eliminated by working with a building enclosure partner versus several subcontractors. The building enclosure partner owns the practices and the procedures, giving the owner and general contractor or construction manager a single point of contact.

Warranty

Manufacturer warranties of the building envelope system components are usually passed from the manufacturer through to the owner. Some warranties have at least a decade-long timetable and can provide peace of mind to the building owner. The manufacturer warranty covers the performance of the product. Labor or workmanship warranties are regularly required on installations and have a typical coverage period of two years. This coverage is adequate because the building will see two full cycles of spring, summer, autumn and winter. If any poor workmanship exists, it can be flushed out and corrected within the warranty timeframe.

One issue that can occur with these types of warranties is if the system failure occurs outside of the workmanship timeframe. For example, glass typically has a 10-year warranty, and if there were a product failure at year six, the glass manufacturer would replace the glass under its warranty. However, the owner of the building would still be responsible for costs associated with the installation of the replacement glass.

Another issue that can arise when multiple subcontractors are involved in the construction is with identifying the source of the problem so that responsibility can be assigned to the appropriate subcontractor. In areas of ambiguity, due to poor coordination and scope of work clarification, warranties become even harder to enforce.

Warranties play a large role in the owner’s decision on what companies to hire. The owner is looking for the added confidence that the building will perform well after construction has been completed. One of the biggest owner concerns of warranties is with the inclusions and exclusions in the scope of work. Typically, the area that tends to have the most common failures is at transitions, where one system stops and another system starts. This is where the issue of “who owns what” tends to be a gray area and reveals a gap in the warranty coverage.

Conclusion

The management and coordination of the design and installation of a building envelope system is the core factor that can prevent or cause performance issues. Communication is the key element in preventing building performance failures or issues. A collaborative approach from start to finish, including the design phase, works better to ensure a high-performing façade. The best approach and one that companies are gravitating toward is the managed building enclosure, in which one contractor is responsible for the scope, performance and warranty of the entire building envelope system.

This article originally appeared in the issue of .