Integrated contract administration and acoustics

by Katie Daniel | September 2, 2016 10:05 am

by Kiyoshi Kuroiwa, P.Eng.
Buildings are a combination of design and construction. On paper, it may all seem to flow and make sense, but a small change in the former can have major impacts on the latter. Similarly, alterations that happen during the construction phase can end up causing significant design problems, affecting everything from acoustics to ambient noise.

For the design intent to remain intact, there needs to be oversight and review throughout the project to keep it on track. Acoustics contract administration may not seem like a necessary investment at the beginning of a design, but over the life of the construction project, overseeing the details regularly can result in savings—and less headaches. While aspects like the position of lighting fixtures can be changed post-construction with ease, noise-control elements are hidden and require breaking down walls to locate the source. Continuous oversight of the project can avoid such complications and costs.

Contract administration 101
Even the most brilliant design has to conform to the reality of site conditions. Since a site may not be entirely conducive to the design, modifications are often needed. In other cases, a contractor may want changes to work conditions. All change requests are subject to two questions: What should be done, and what can be done? While every modification may seem necessary, contractors must also consider budgets and timelines around the requests.

Before construction begins, there should be complete specifications and details in the drawings. No matter how detailed the drawings, there will always be elements—big and small—needing modification once the building construction begins.

A contract administrator ensures the details in the drawings are followed as precisely as possible. Most contractors are familiar with a contract administrator from the architectural side, but having contract administration managed entirely by the architectural side of the team (which would include mechanical engineers and others) can be a disadvantage. If acoustical questions were raised, the acoustical engineers working on the project would have to familiarize themselves with the construction modifications before they could provide answers. Thus, construction projects should have the acoustic consultant integrated into the contract administration phase.

As acoustical designs become increasingly complex and unique to each building, there are more involved discussions when changes are made. Although engineers and architects bring a great deal of expertise to a project, modifications may require more specialized knowledge of acoustical issues.

Even small adjustments or changes can lead to unanticipated acoustical problems. Adding an extra layer of drywall can change the flexibility of a wall and alter the acoustics of a room. Similarly, additional bolts in a fitting can lead to sound traveling to an unexpected space. Unlike positioning lights or adjusting door seals, fixing acoustical problems once the construction is complete is an expensive undertaking since it usually involves tearing materials down and rebuilding.

It is easy for small things to impact the building code requirements. When referring to vibration isolation, contract administrators will not only watch to ensure a contractor uses 25- or 51-mm (1- or 2-in.) springs, but they also need to ensure the load on the spring is adequate so it works properly. A spring with a 45.5-kg (100-lb) rated load being loaded with only 13.6-kg (30-lb) would not be appropriate; however, a spring loaded at its rated load provides maximum benefit.

Creating a single point of contact to oversee the design’s implementation, and combining it with acoustical expertise, means construction projects can stay true to the design while ensuring the building is acoustically sound. The acoustics contract administrator can become familiar with the design ideas and be focused on catching potential issues before they become a problem. It means she or he can make on-the-spot decisions about modifications and keep a project moving forward. Also, an experienced contract administrator can bring knowledge from previous projects and use this knowledge on the current modifications.

Seamlessly integrating acoustics
The need to stick to deadlines can lead to decisions made under pressure to ensure a project can remain on schedule. Small or quick changes made without looking at the bigger impacts could mean literal echoes or vibrations in strange places. Additionally, acoustical treatments are one of the most misunderstood elements in a building, with some changes made based on the wrong information.

For example, while most contractors understand conduits need to be run in the wall, it is important to understand the acoustical reasoning of how to run an electrical conduit so it does not affect the wall’s acoustical separation. The separation is solid when there are two one-sided walls, but this acoustical separation will be lost as soon as a conduit is placed across two studs. A good acoustic wall should have one wall moved but not the other. Once a pipe is placed in between and screwed tight, both walls will move together and the acoustic benefit is lost. This is particularly important in condominiums where dwellings are close together and privacy can be a concern. According to the International Building Code (IBC), wall and floors/ceilings of dwelling units and sleeping units have to satisfy a sound transmission class (STC) rating of 50.

While most contractors strive to ensure buildings are solid, acousticians want portions of the building to be flexible to reduce sound propagation through the building structure. This needs to be communicated to an entire project team. However, this should not be perceived as a battle between the various parties involved in a construction project. It needs to be a collaborative effort whereby working together, both parties may find a better way to implement the design and reach the acoustical goal. Startup meetings with the contractors, acoustically related mockups, and implementation discussions can all help get the contractors on the same page as the design team.

With specialized knowledge and expertise, the acoustics contract administrator can be a wealth of information that can head off problems before they become issues. By providing insight into elements such as acoustic door seals or vibration isolation, a contract administrator can provide information on how these treatments can be used to create an acoustically sound building.

They can also provide accurate information on acoustics and how materials will impact the sound. One of the common myths is glass fiber in walls absorbs sound, but this is not true. Rather, the material acts as an ‘enabler’ in the wall to help block out sounds and allow the wall’s acoustic performance to be realized. Adding a glass fiber baffle above a partial height wall to block sound will not work—other modifications should be considered instead.

Acoustical contract administrators can help correct these common mistakes early in the process and can answer questions throughout the project. Acoustics is becoming more technical and the contract administrator can provide both expertise and education to help contractors better understand how small changes can have big sound impacts. By being available to answer questions, contract administrators can recognize when the acoustics may be compromised and ensure the minimum sound requirements are met.

Ideally, an acoustics contract administrator should be involved from the beginning of a project and be onsite at least once a month to provide input and expertise. While it represents more upfront cost to a contractor, it will ultimately be more economical than tearing apart areas that have acoustical issues after completion.

Working as a team
One of the first site visits should include a meeting with the contractors and contract administrator so everyone can go through the design and identify where acoustics can be affected. The discussion should review the design and determine where the obvious acoustical problems could arise such as conduits in walls that are not always visible on the drawings.

All the details should be outlined before the project begins because it is imperative the treatments be outlined in the contract. Acoustics contract administrators can only administer what is in the contract. By taking the time to outline a detailed plan that includes the acoustical treatments, it will ensure the design vision is realized without compromising the acoustics.

Record the details
The contract should include all the details of a project. It is difficult to administer a project and make recommendations if the initial scope or budget is incomplete. Good acoustics may require additional work and increased budget, so one must be prepared before construction begins.

Develop a strong relationship with acoustical consultant
Every project requires experts to complete. By partnering with the acoustical consultant, one can avoid common sound-control myths and learn from any educational opportunities that arise during a project. Knowledge can be carried forward into new construction projects.

Open communications
With so many people responsible for completing a construction project, pressing timelines, and limited budgets, it is important to know where there is flexibility in the system. By working together, the design team, contractor and contract administrator can consider all points of view to find a solution to any issues.

Having regular reviews and input from an experienced acoustics contract administrator can head off the problems before they lead to expensive repairs after completion. Ultimately, acousticians strive to have their work go unnoticed. Success is having acoustics completely integrated into the design of the building so its effects can be enjoyed, but not seen. This cannot be accomplished by acousticians alone. It requires significant collaboration between the architects, contractors, engineers, designers, and contract administrators, as well as building owners, to deliver a successful finished product that resonates.

Kiyoshi Kuroiwa, P.Eng., created and leads Aercoustics’ contract administration department. He is responsible for the acoustic design and contract administration of architectural projects such as the Aga Khan Museum and Ismaili Centre in Toronto and Simon Fraser University School for the Contemporary Arts in Vancouver. Kuroiwa has applied his experience playing piano and percussion in orchestras to the acoustical design of projects. He can be reached at kiyoshik@aercoustics.com[1].

Source URL: https://www.constructionspecifier.com/integrated-contract-administration-and-acoustics/

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