Opening the Door to Better Classroom Acoustics

Slatington Elementary ClassroomLast year, I was presented with a unique opportunity to apply our building science research into a real-life application — the renovation of an elementary school in northeastern Pennsylvania. Originally built in 1973, the school was transformed from an open concept interior space into individual state-of-the-art classrooms. Superior acoustical comfort, which can contribute to improved student performance and teacher retention, was a top priority in this field study as well as an analysis of the overall indoor environment that included air quality, thermal comfort and visual comfort measurements.

Our goal was to investigate the impact of installing different, high-performing interior acoustical ceiling and gypsum wallboard system solutions in six new classrooms constructed in the third grade student wing. Acoustical tests were conducted in each classroom to determine sound absorption and interior partition sound transmission levels, as well as major sound flanking paths.

As a leading manufacturer of ceilings and wall products, our team is well versed in the myriad of product specifications and configurations for our products. However, during the testing, I had an a-ha moment of sorts regarding the doorways to the classrooms.

Specifically, I realized that even though it is well known that acoustically isolated, airtight door assemblies improve classroom acoustics when used in conjunction with high-performance gypsum board and ceiling products, these elements are often specified independently rather than a comprehensive acoustical system. This is a challenge that I have always been aware of, but seeing it so clearly in this study led us to ask: what could we do about it?

Our curiosity led us to ASSA ABLOY, the global leader in door opening solutions. Through our alliance, we’ve uncovered easily accessible solutions found in door and frame systems, to address acoustical challenges and reduce the sound reverberation that further complicates noise issues in classrooms.

We look forward to sharing more detailed findings during Greenbuild 2013 through a dedicated education session at the Saint-Gobain Learning Lab. Please join us at the session or leave us a comment below to continue the discussion.

Building Knowledge Experts at AIA2013 – Expertise that Inspires

AIA2013CertainTeed Technical Marketing Manager for Ceilings Bob Marshall conducted a session at AIA2013 on Ceilings in the Health Care Segment.  During the presentation while Bob was discussing the noise levels in hospitals and how it impacts healing, the question was raised:

“Why do we accept higher noise levels in hospitals if we know that it impacts the patients’ ability to heal?”

Two things work in our favor. Acoustical standards and guidelines are well documented and hospital administrators are getting validation regarding just how much acoustics matter and they are starting to make better choices when upgrading their facilities. We have to keep in mind that hospitals are very competitive but we are starting to see changes that have positive effects on patients and recovery. Rooms are painted in pastels now with artwork on the wall so administrators are starting to make the environment more pleasant for the patients.  At some point, they will have to address the noise levels as they relate to healing to continue to remain competitive. There is research that will speak to just about every architectural decision from an interior perspective. We are just validating and giving them the tools to go ahead and sell the acoustical benefits for making these changes.

If you have a question or comment, we would love to hear from you. Although AIA 2013 is over, we know these questions will continue to be raised.

Designing Buildings with the Future in Mind

 

Glenn Jackson

Glenn Jackson

Glenn Jackson is Director, Corporate Marketing for CertainTeed Corporation

Part of the conversation regarding sustainable design is a move toward improving performance and addressing specific needs of the potential occupants of a particular space.

The building industry has historically designed buildings based only on the need to provide a place for people to live, or go to school or to heal when sick. 

Today, so much more is taken into consideration. Product manufacturers, the design community and even building owners are much more focused on asking “What problem are we trying to solve” or “What elements need to exist in a building to help address performance based criteria such as, learning, healing, innovating and working.

Creating unique spaces is becoming more the norm even within what we refer to as vertical markets or niche markets which meet the needs of a particular industry.  Standards for design or performance may exist within a vertical market such as educational facilities or healthcare facilities but each project will have specific needs driven by geographical and environmental conditions, uses for the spaces, aesthetics and building owner preferences.

Some of the areas most critical to building sustainable and performance-based structures are thermal and acoustical comfort which is not seen but does affect our physical comfort and wellbeing.  Visual comfort speaks to our need for natural light.  Innovations in glass products are revolutionizing the industry.  Indoor air quality is crucial in all buildings and systems, and products are available to address most concerns for creating clean indoor air.

In the end, the efforts made to design and build high-performance, sustainable, buildings with solution based systems will provide significant savings for the end users.

It’s Not Just Wallboard Anymore

 

Ashwin Himat

Ashwin Himat

Ashwin Himat is Director of Marketing – North America for CertainTeed Gypsum

New innovations in technology are redefining building products industry-wide. Manufacturers are improving products today based on solutions to environmental concerns and to address indoor environmental quality. Wallboard is no exception.

Historically, wallboard enabled residential and commercial construction to provide better fire protection and a flat, smooth surface that could be easily painted or wallpapered. Because of the recycled content of wallboard, it has always been considered a sustainable product but its function rather than its features were the primary selling point.

The drivers for innovation of wallboard products predominately came from the commercial build community. Earlier innovations in wallboard provided moisture resistance for areas of buildings with high moisture such as bathrooms and kitchens. With increased concerns and claims regarding mold in buildings, a technology was developed to provide mold and moisture resistance to wallboard.  Mold is a potentially serious health issue for people so the ability to include a mold resistant wallboard in a home or building susceptible to mold reduces the potential.

With the rapidly growing awareness of the importance of indoor air quality and its impact on health and productivity, recent technology innovations have led to the introduction of wallboards that clean the air.  By removing volatile organic compounds (VOC’s) such as formaldehyde and other aldehydes from the air and converting them into safe, inert compounds, these wallboards can improve indoor air quality for generations. 

In response to the growing marketplace demand for acoustic comfort, manufacturers have increased innovations in the area of noise-reducing gypsum board, specifically designed for wall systems requiring high STC ratings where acoustic management is needed.

The commercial build community is aware of these advancements in wallboard and they are including them in specifications especially in the educational and healthcare arena. But these wallboards adapt well to residential construction as well especially when designing custom homes that may include home theaters or music rooms.

Homeowners need to be educated about the options they have when either building a new home or expanding an existing one.  Decisions made about the walls and ceilings of a home should be carefully considered because ones overall comfort depends on it.

Wallboard is not a one size fits all product any longer so when it comes to improving comfort and indoor environmental quality remember to consider the best solutions for your walls and ceilings.

Solving an Acoustical Problem in a Retrofit Environment

 

Stan Gatland

Stan Gatland is Manager, Building Science Technology for CertainTeed Corporation

It can be a challenge to control the acoustics in older buildings when they are repurposed for multiple business uses.  One example is a call center situated in the middle of an office building, surrounded by cubicles of other workers and offices with many hard surfaces – glass, wallboard and wood doors. The perimeter of the call center has a low suspended ceiling with a decorative hard wood finish that amplifies and reflects the various sounds typical in an open plan office setting – loud telephone conversations and office equipment – carrying the disruptive noise throughout the floor.

The building owner had some ideas on how to improve the space but decided to work with an acoustical consultant to confirm the noisy conditions with measurements, as well as make recommendations on how to improve the space acoustically.

Acousticians commonly refer to highly sound reflective rooms as “live” or “reverberant.” Open plan office space should be designed for both good speech privacy and poor speech intelligibility.  Typically, you design for privacy at work stations and make speech unintelligible between adjacent areas by controlling background noise levels and reverberation time – the length of time it takes for a sound pressure level to decay or dissipate.

The results confirmed that background noise levels were high and intermittent and reverberation times exceeded the maximum recommendation of 0.60 seconds at most locations on the floor.

Another metric that was used to characterize the space was the speech transmission index (STI). STI is a measure of the ability to understand speech in a given space with the sound source coming from different directions or locations.

In open plan office settings, you want STI values to be low or poor meaning that people can’t understand each other from different locations.  Most locations had fair to excellent ratings creating a poor acoustical environment.

The recommendations provided by the consultant to solve the problem in this office space were:

  • Change the entire ceiling to high absorption suspended tile or use functional absorbers (hanging panels in the box like orientation)
  • Add some absorptive treatment to office doors or walls facing the open office
  • If not enough, use background masking noise.

It is expected that if the summary improvements were made it would improve comfort and maybe morale and productivity for the employees.

Time will tell. Do you have any examples of acoustical retrofit to share?

A Sound Affect on Human Centered Design

I was once told good (and bad) acoustics is something you experience; something you can feel, even if you don’t know what it is. I am always impressed at how real this experience can be.

Research shows that people work more productively, communicate and learn more effectively, and heal more efficiently in environments with good acoustics.

Recently, Jill Robles, the Ecophon Architectural Sales Manager in New England, and I had the pleasure of working with the Institute for Human Centered Design (IHCD) in Boston, Massachusetts.  The IHCD is an international non-governmental educational organization committed to advancing the role of design in expanding opportunity and enhancing experience for people of all ages and abilities through excellence in design.

A large lobby area outside of a conference room is utilized frequently for meetings.  It is a great space for informal gatherings after presentations but the acoustical condition made it uncomfortable and difficult to hear. Conversations can be a challenge without proper sound dampening because of heavy reverberation and increased sound pressure levels.

Prior to our “acoustical intervention”, members of the IHCD team were skeptical that the acoustical challenge could not be overcome, and that any acoustical solution might resemble that of an “ugly burlap sack”

Our solution? Shaped, free-hanging, acoustical sound-absorbers hung from the existing gypsum ceiling at varying levels to enhance the contemporary and spirited design in an area that has many acoustically reverberant surfaces. We took simple before and after decibel (db) readings, and the sound pressure levels decreased by 13 db when people were talking softly. It may not sound like a lot, but a 2-3 db reduction is like having two car engines running side by side and turning one of them off!

Though acoustics was the primary reason for the treatment, these noise absorbing systems were far from the feared “burlap sack”. Members of the IHCD staff commented on how they served as artwork. The shapes and levels complimented the suspended lighting, and even allowed some flexibility in how light was dispersed.

But the true test was during a presentation weeks later, co-hosted by the International Interior Design Association (IIDA), Ecophon, and CertainTeed. Attended by more than 60 guests from the Architectural, Design, Acoustical Engineering, and Interior Design Communities, the presentation by European speakers discussed how acoustics impact people based on research from around the world.

After the presentation, the guests mingled, chatted and relaxed. The most interesting part is that everyone congregated in the area that received the acoustical treatment, while the other areas in the facility were empty. To me, this demonstrates a good acoustical experience… nobody knows why they feel more comfortable in a space, but they naturally communicate better in it.

Quantifying the Value of Sustainability Going Forward

Lucas Hamilton

As we continue to improve energy performance, acoustics, comfort and aesthetics in our buildings, we are left with the challenge of quantifying the impact of these practices and how much they influence our quality of life.

This is a needed validation of sustainability – evaluating the effects that improving systems has on the occupants over a period of time.  While we are preaching the gospel to improve the performance of our buildings by including more natural light, better indoor air quality, improved acoustics and overall comfort are we quantifying how these changes improve employee or student performance in an improved environment?

For example, we have a need for connectivity. Older buildings were not built to provide ample natural light needed by people. Workers who sit in cubicles with no window tend to feel disconnected because they lack connectivity. Think about it when you enter a room, do you take a seat that enables you to look out a window?

Are we adequately documenting whether:

  • Students test scores improved because they could hear the teacher better?
  • Worker productivity increased because they had access to natural light?
  • Absenteeism decreased because of improved indoor air quality?

Some decision makers will argue that there are only two kinds of decisions: rational (based on facts) and irrational (not based on facts.) I would suggest they change these terms to fact-based and faith-based. In our private lives we make decisions based upon faith all the time and we are completely comfortable doing so. I think we need to develop more data to help less confident decision makers defend their faith- based decisions with some facts. If we are successful, eventually some of these decision makers will develop enough confidence to be truly innovative.

Are there other ‘quantifiables’ that we should consider to justify the decisions we are making now and in the future? I would like to hear your thoughts?

Lucas Hamilton is Manager, Building Science Applications for CertainTeed Corporation

School Districts Are Embracing LEED Buildings

Lucas Hamilton

Large urban and smaller sub-urban districts alike are increasing their focus on building schools that are certified by the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) program because this practice results in more state funding.  Schools get funding based upon population – the actual number of students that they teach every day- not the number of school age children living in their district.  That is a number that is taken daily called attendance. 

If  40 percent of  a school district’s population is not showing up, that district will receive 40 percent less state funding than may be deserved. While the goal of the school district may be to educate our children, the first task is to get kids to show up. This is not just for all the right reasons, such as, the importance of learning and that it is in the best interest of society in general but also because that is the way the school district gets paid.

Statistics show that building more sustainable spaces results in increased student attendance over schools constructed with outdated techniques and materials (and decreased staff absenteeism due to illness).  Building sustainably also improves the acoustics and indoor environmental quality of the building. Incorporating acoustical ceilings, noise reducing gypsum wallboard and adequate levels of insulation contributes to the creation of optimum learning environments. Recent studies have shown that optimizing learning space acoustics ultimately improves student retention and test scores (another critical metric by which schools are judged).

For some urban school districts, the school buildings themselves may be the nicest spaces that the child will be in all day. While this is considered collateral benefit, it’s well worth it for the school district to invest in sustainable spaces because the children feel better, they are healthier, more positive about the experience and will be in the classroom on a more consistent basis.

If you look at the upfront costs to build a school, why would a school district strapped for cash build a school above and beyond code?  Because it will pay for itself!

 Lucas Hamilton is Manager, Building Science Applications for CertainTeed Corporation

Would People Use the Stairs More if They Were Nicer?

Lucas Hamilton

Think about the stairs in the average building.  They are simply stairwells -very claustrophobic – very unpleasant – very utilitarian.  In general, they are often not attractive spaces.

I recently visited ZGF Architects at the 12 West building in Portland, Oregon which is a LEED Platinum certified high-rise building. One of the really cool features of ZGF’s office space in this tower is the open stairs between floors. If you visit the firm’s web site you can actually see pictures of the stairs under the “interiors” tab.

When you were in these stairs you noticed they were beautiful.  They weren’t wells they were open to the spaces.  The vertical space of the stairs became a connector of the spaces in the building.  They were airy and bright, they also incorporated the environment of the floor in terms of the acoustics and appearance.  You saw people stopping and talking on the stairs.

It made me think ‘If the stairs were more appealing would people be willing to use them?’  The designers of this building thought so and they were right. 

One of the concepts put forward for reducing power consumption in buildings is rethinking how we can incorporate stairs between floors.  Not only does it save energy, it adds to the overall aesthetics in the design.  An unrelated benefit is that it increases the cardiovascular benefits for employees and visitors. As we consider how we might change the ways we think of and incorporate these spaces in our building, we must remain mindful of the science of air flows and how large columns of air behave. There must be an eloquent solution which combines form, function, and efficiency.

Have you seen any examples of the creative uses of stairs in buildings?

Lucas Hamilton is Manager, Building Science Applications for CertainTeed Corporation

Designing Environments for Sound Control

Stan Gatland

Traffic, door slams, vacuums, toilet flushes, TV’s – these are just some of the everyday noises that can affect your comfort.

Acoustical comfort, created through effective sound control, should be considered in all buildings. Many practical and economical solutions to sound-related problems are currently available to architects, engineers, contractors and building, and home owners.

Most noise control situations can be managed whether it’s from airborne sounds – sound that is directly transmitted from a source into the air like outside traffic, music or voices,- or structureborne sound – sound that travels through solid materials like footsteps, door slams, or plumbing vibrations.

There are four goals to providing a superior acoustic environment:

  • Reduce sound reverberation time (echo factor)
  • Limit airborne noise (sound transmission from space to space)
  • Reduce impact noise
  • Minimize background noise

The reduction of sound reverberation time is accomplished by employing sound-absorbing surfaces, such as fabrics, carpeting and acoustical ceilings. The best plan is to configure those spaces to reduce, rather than amplify the sound energy.

When limiting airborne noise, one important consideration is to design high sound transmission class (STC) assemblies. STC is a laboratory measurement used to study the resistance of a wall, ceiling, or floor to the passage of sound. The higher the STC number, the more the sound is deadened. Also, try to enclose or separate spaces with group activities that may create chatter from common areas, using acoustically efficient walls.

To reduce the transmission of impact noise, you can design high-impact insulation class (IIC) assemblies. Isolate finished floors and ceilings by installing resilient underlayments, by using sound-absorptive floor coverings and by using resilient ceiling suspension systems that include sound-absorbing cavity insulation.

Design your HVAC systems to absorb energy and reduce background noise so airborne noise isn’t transmitted through the ductwork. Mechanical equipment should be isolated using vibration dampening techniques and high sound transmission reduction enclosures.

Creating a quiet environment makes for happier homes and offices.

Stan Gatland is Manager of Building Science Technology for CertainTeed Corporation