HVAC

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Birmingham Mayor William Bell assists with ground breaking at ILR

There is something special about every project we build. Some bring vitality to communities. Adaptive reuse breathes new life into existing–often historical–buildings. LEED projects promote sustainability.

Last fall, we broke ground on a project that was more than special. It’s an honor.

Independent Living Resources provides community-based, non-residential services and advocacy for those living with disabilities. The new location we are building in Birmingham’s Civil Rights District seems more than fitting. As IRL Executive Director Dan Kessler, told The Birmingham News, “Human rights is a part of (the Civil Rights) mission, and disability rights is big part of that movement.”

Beyond all ILR gives the community, what most impressed us about their folks was the focus on something called Universal Design.

Universal Design centers on accessibility for as many people as possible. This can be in the form of environments, objects and systems. For followers of the concept, buildings should to be usable to the greatest extent possible by everyone, regardless of their age, ability or status in life.

Independent Living Resources is able to take universal design to a new level, because the majority of people on staff have disabilities. Involving them in the design process has been particularly enlightening.

Here are a few ways Universal Design is being used at ILR:

Door Openers. Standard accessible entrances include a push button for access, which excludes those who lack upper body mobility. ILR will be installing a version that can be activated using a wheelchair footrest. These will be placed inside and outside at the front and back doors.

Quiet Room. Individuals with stress disabilities or those prone to migraines can use this space to relax. It will be equipped with a daybed, and no cell phones or work materials are allowed inside.

Parking spaces. The 14 spaces closest to the building are divided by bollards and feature a detectable paver system for the vision-impaired. This also provides good visual separation for all drivers.

HVAC. The building has been divided into smaller HVAC zones, giving more control of the temperature in personal workspace and increasing the comfort of those people who work and visit.

Workstations. Areas such as the reception desk will have low and high transaction counters for better access for those who are doing business from a wheelchair.

Light. The lighting has been designed to minimize triggers for people who suffer seizures and other similar conditions. The open workspace features lots of windows, and glass partitions let the light flow throughout the office.

Site Selection. The building is located with convenient access to public transportation and sidewalks have been modified with ramps down to the street for access by people with disabilities.

Community Connectivity. The site is within walking distance of the power and gas utility companies, the Social Security office, and several other public buildings and community service organizations.

What we’re learning is that the principles of Universal Design make sense. Open spaces, wider halls, additional light and facilities that can be modified don’t just benefit people with disabilities. They make buildings better for us all.

What accessibility changes have you made to make your facilities better for everyone?

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Merrill Stewart is Founder and President of the Stewart Perry Company, a commercial building contractor based in Birmingham, Ala. Contact him via email

 

 

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Last week, I was having a conversation about pricing on an HVAC system with Heath Cather in our office. Why had the mechanical engineer chosen hot gas reheat? It’s more expensive and sometimes unnecessary, I offered.

He mentioned a trend he’s noticed. With all the mold law suits lately, we are seeing recommendations for a sure bet against moisture: hot gas reheat.

What is hot gas re-heat?

With this system, you have two coils in the air handling unit. The air first travels across a cooling coil which de- humidifies, then it crosses the hot gas coil that raises the air temp back up 15-20 degrees to further dehumidify and render the air neutral, eliminating over-cooling.  Once the thermostat calls for cooling, the hot gas drops out in order to lower the space temp.

Why are we seeing more use of hot gas reheat?

I talked with a mechanical contractor relationship of ours for details. This is what he told me:

Recent requirements to introduce large amounts of outside air into the workplace can result in the rise of the  indoor humidity level in the space. People want to combat this by purchasing a unit with excessive cooling tonnage, a “bigger is better” mentality. The over-powered unit causes the system to short cycle, not running long enough to de-humidify. We’re left with excess moisture, which can lead to mold.

Thoughts on combating the moisture with hot gas reheat:

  • Energy code limits the use of electric re-heat to 42,000 btu and below.
  • With hot gas reheat, the average 5-ton unit sees a price increase between $2,800 and 3,000, rising significantly as the tonnage increases.
  • If the space is cooling, it is de-humidifying, whether humidistat is calling or not.
  • Humidity control from a properly sized unit can lead to energy savings. Lower humidity in summer will make you feel more comfortable at 75-77 degrees, while if the humidity is high , 70-71 degrees may not seem comfortable. The opposite is true for winter operation.

Takeaways:

Hot gas is more expensive. A standard  and properly sized system has been proven to be just as effective in humidity removal and comfort control.
Know what you’re building and communicate it. What will the building be used for, and are there special climate issues involved? This is another reason design build works for many clients.
Application is key. HVAC is not a one size fits all discipline.From a contractors stand point, we see the addition of hot gas reheat on the increase and the majority of the time justified.  However one should stop and evaluate: do we really need this, or is it just insurance for a 3rd party?

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Merrill Stewart is Founder and President of the Stewart Perry Company, a commercial building contractor based in Birmingham, Ala. Contact him via email

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HVAC (Heating, Ventilating and Air Conditioning) systems have evolved and gotten better with technology.  Matching system requirements with the need and with quality will always trump the bells and whistles. Over the years I have worked with a number of HVAC subcontractors and a few thoughts come to mind that might be useful:

SYSTEM ENERGY EFFICIENCY
Depending on the application and occupancy, a higher SEER (Seasonal Energy Efficiency Rating) for equipment is preferable most of the time. A higher the SEER means more expensive equipment, but the lower operating cost is a win for energy and your occupants.

SYSTEM MAINTENANCE
When selecting the right HVAC system, keep in mind the occupancy type vs. the long-term cost of maintenance. Chilled water/boiler systems will require preventive maintenance for a chiller, cooling tower, boiler, heat exchanger, etc to a greater extent than a DX (direct expansion) unitary system. A DX split or packaged system will be a handful of components that are readily available and replaced at a minimal cost.

INSTALLATION COST
Most of the HVAC system cost is in the equipment and control system. Both are important to system sustainability. Duct systems normally require little maintenance if quality materials, closure systems, sealants and higher “R” value insulation are used. Providing the correct type of air distribution is just as vital as selecting the equipment and will maximize coverage, eliminate the draft effect on occupants as well as air noise transmitted from the device due to a high velocity (fpm) of air.

BUILDING AUTOMATION

There’s a big debate over whether to use programmable thermostats or fully automated systems. Most projects perform well with proper zoning and programmable thermostats as opposed to extensive control systems that require increased up front cost and service for the life of the system.

Each control system has a place in the “right choice column.” A commercial building operating from 8 a.m. to 5 p.m. will have different needs than an institutional building or medical facility. The challenge with a fully automated system is it’s almost always proprietary in nature and can only be serviced by the brand vender, leaving the building owner with no other option for value shopping. A stand-alone zoned system with programmable thermostats is fairly user-friendly and can be serviced by any commercial company. This dramatically reduces long-term replacement and/or maintenance cost for the end user.

To me, when it is all said and done, you need a cost-efficient system that will deliver the performance and can be maintained without having to go to the banker every time a failure happens.

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Merrill Stewart is Founder and President of the Stewart Perry Company, a commercial building contractor based in Birmingham, Ala. Contact him via email.

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