Economic Recovery and the Clean Energy Revolution

Recovery, Growth, and Clean Energy

Companies, non-profits, government organizations, healthcare facilities, and institutions of higher learning will soon look beyond survival to recovery, and eventually growth. It is a rising movement called the Clean Energy Revolution. It may be difficult to visualize this given our current state of affairs, but this too shall pass, and better times will come. Our culture has seemingly lost its ability to think and plan for the long-term; priorities, politics, and results are driven by short-term metrics. As such, I believe that we should use this opportunity to reinvent, rethink, and rebuild with the following attributes in mind: organizational resiliency, serving the common good, equability, and sustainability.

Sure, this all sounds great. But what do you mean?

I tend to think of nearly every problem (opportunity) in terms of the Pareto Principle, better known as the 80/20 Rule. It asserts that 80% of outcomes result from 20% of all causes for any given event. In business, for example, the goal is to identify what actions or inputs are most productive and prioritize them accordingly.

Bar graph of the pareto principle, effort vs result in red and blueSo, as it pertains to this concept, I believe there are two inputs we should focus on with respect to economic recovery, arguably the biggest global challenges of our time (COVID-19 + climate change), and the attributes I mentioned earlier (Resiliency, serving the common good, equability, and sustainability). Speaking broadly, they are 1.) Energy and 2.) Health.

No, seriously. I get it. Give me specifics.

OK, first we need to deal with the public health crisis at hand. Social distancing, wearing masks, and limiting travel — these practices are already in play and are driven by behavior. But the one thing we can do to make people feel more comfortable returning to our prior norms, such as returning to work, shopping, eating at restaurants, etc. is to invest in the

health of our buildings. By focusing on healthy buildings (HBs), we will not only make people feel comfortable, but help reduce the spread of the virus and make ourselves more productive. This leaves our employees, customers, and any other stakeholders feeling better and more productive.

So, what constitutes a healthy building?

First, seek to understand sick building syndrome (SBS) and building related illnesses (BRI). The EPA defines SBS as a situation in which occupants experience acute health and comfort effects linked to time spent in a building, but no specific illness or cause can be identified. Indicators of discomfort include headaches; irritated eye, nose, or throat; coughing, dry or itchy skin, nausea, and difficulty concentrating among other symptoms. Occupants report relief soon after leaving the building. Physical evidence within the building itself includes an incoming draft at the front door; hot or cold spots throughout the facility; condensation on ceiling diffusers; slippery floors; mold; hard to open doors, high energy expenses, and other contributing factors. BRI is indicated by occupants reporting of symptoms such as cough; chest tightness; fever, chills; and muscle aches. These can be clinically defined and require some recovery, after leaving the building.

Holy cow. I hadn’t thought of all this being related to buildings. What are the primary causes of SBS and BRI?

Poor HVAC performance such as inadequate ventilation and negative building pressure.

OK so, how can I invest to make my building healthy as you suggest?

This is a loaded question. There are A LOT of things you can do. I’ll try to keep this brief.

First and foremost, make sure the HVAC system has been well maintained. And think about the health issues described above. Are these currently problems? If not, you may not need to do much, though there’s certainly always room for improvement. If these are problems, consider consulting with an expert on HVAC and healthy buildings. Make sure they’re independent of whomever is responsible for your maintenance and certified to do so. They’ll likely perform an investigation and assessment on the HVAC system, as well as indoor air quality. The factors to be evaluated (and adjusted) on the HVAC system include but aren’t limited to verifying equipment operation; checking building pressure; inspecting filters, belts, and fans; and finally asking questions about comfort. The primary factors that influence indoor air quality are the occupants; the HVAC system; pollutants and their pathways; and internal and external contaminants such as chemicals, smoke, grease, molds, and pollen.

After these initial assessments are complete and adjustments made, get some form of system to monitor building health. Think of these monitors like having a FitBit for your building; empower yourself with data to maintain proper health. There are plenty of options out there and what you install should monitor some of the following attributes: differential building pressure (the #1 indicator of overall building health); C02; relative humidity; and temperature. Monitoring these core attributes will cover the 80/20. Other important, albeit

less impactful, attributes to monitor may include volatile organic compounds, water quality, noise pollution, occupancy, lighting quality, and energy usage.

Building health alone covers more ground than I imagined. But you also mentioned energy. What can I do there?

Invest in Energy Efficiency (EE), Renewable Energy (RE), and Clean Energy Transportation (electric vehicles or EVs). The Clean Energy Revolution is way more than just building health alone.

Why? And, how does this relate to helping with economic recovery?

There are a number of reasons. Quite honestly, too many to cover without writing a book. So, again, I’ll focus on the 80/20.

Economic Opportunity

First, and most pressing is economic opportunity. Energy, and the cost of it, flows through everything. Think about that. The cost. of. energy. flows. through. everything. As far as EE goes, the cost of energy saved is the lowest cost of energy. This is a no-brainer with a guaranteed ROI. Further, the cost of RE is at or below the cost of traditional fossil-fuel based sources, depending on the state, scale, and application. And EE, RE, and EVs are driven by technology — not sources of fuel. In terms of economic growth, every measure of kWh or BTU saved by EE or generated domestically by RE translates into wealth we are not exporting to foreign nations. Put that into perspective, relative to the cost of energy, which is buried in the cost of everything.

Moral Imperative

Making the transition is a moral imperative during the Clean Energy Revolution. The science is clear and indisputable. We are harming our earth. If we do not reverse course, soon, the damage will be irrecoverable. Remember how quickly COVID-19 swept the globe and how we’re still reeling from its devastating impacts. Climate change is a crisis in slow motion. Yet, unlike this virus and the subsequent public health crisis, the impact will change the face of the earth — and humanity —forever. I cannot, in good conscience, put that burden on my children and grandchildren. We have borrowed at their expense for far too long.

National Security

Making the transition is a matter of national security. How many global conflicts have been fought over the allocation of natural resources? This strategy not only protects the

lives of future generations through preserving the earth but, quite literally, may prevent them from fighting avoidable wars. When we leverage technology for our energy, we are not subject to the whims of foreign nations and their strategic interests. As the world seems increasingly less stable, this also seems like a no-brainer, let alone the cost savings relative to current military spending. Simply put, an investment in clean energy is an investment in our own national security.

 

Shaping Our Future

Finally, consider how past industrial revolutions have shaped our nation. The emergence of water, steam, and coal as sources of power and how they expanded industries such as railroads, steel manufacturing, electric lighting, automotive, and the digital revolution — which brought forth widespread globalization, low-cost economies, and new business models. What is next? I pronounce we are in the beginning of the Clean Energy Revolution. And once we have hindsight, I truly believe it will surpass prior examples in terms of how it changes the world. Do we want to be the leaders of this revolution? Or will we continue to cede this opportunity for other nations to embrace? If we do not lead this New Age, what’s next for America? Let’s dismiss coal and oil to embrace the future. The potential for job growth and opportunities for continued innovation are beyond comprehension.

Creative Financing Pays for Itself with Intelli-Hood

Drastic Turn

2020 has been the most unique year to date, especially when it comes to the economy. Coming off 2019, the economy was strong, companies were reinvesting and spending money. The economy looked like 2020 would be another great year — until March. Enter COVID-19; companies that could endure the pandemic had to pivot fast. Predictions for a record year were gone in a moment. For months, businesses across the country shut down.

Like other businesses, Melink tried to come out the other side of COVID-19. Many felt more timid than ever about spending cash, and understandably so. Numerous projects put on hold as capital expenditure budgets froze for 2020, 2021, and even 2022 in some cases.

Melink’s company mission is to change the world one building at a time. We achieve this by implementing energy efficiency and renewable energy solutions into commercial facilities for decision makers. Intelli-Hood is a Demand Control Kitchen Ventilation (DCKV) system that saves money by reducing monthly operating expenses in commercial kitchen facilities. Often, Intelli-Hood pays for itself in one to three years, making it an attractive energy conservation application.

 

Intelli-Hood Controls

The question arises: How do we change the world one building at a time with spending on an indefinite pause? 

 

Creative Financing Solution

I worked with a university that wanted to implement Intelli-Hood in a kitchen. Without any utility rebates taken into consideration, the $62,000 project would pay for itself in less than three years. Everything was moving smoothly until COVID-19 put everything on pause. But Melink’s committed to working with customers and customizing energy solutions. As a result, discussions were continued with the university. We were able to come up with a creative financing solution that’s win/win for all parties: an Equipment Loan Program. Thus, the customer paid nothing out of pocket, while simultaneously being cashflow-positive the second we walk off the job site. Working with a lender, we got the $62,000 financed for the university over five full years at monthly installments of $1,287. This was a total investment of $77,220.

The Savings Stack Up

At Melink, our proposals come turnkey, along with a custom Energy Savings Report. The reports give an idea of how much money you will save with Intelli-Hood. In this instance, the customer was going to save more than $18,000 in energy savings the first year alone, resulting in a positive cashflow of almost $3,000. On average, utility rates go up 3% every year, meaning that with the customer locked into an installment payment of $1,287 for 60 months, the positive cashflow will continue to increase year over year. After five years, the loan will be paid off in full and the benefits really kick in, saving more than $20,000 per year. Thus, creative financing creates more opportunities for customers to save on energy costs.

Looking at a 10-year period, the customer is going to save more than $130,000 without having to pay anything upfront. While a traditional purchase would save more money ($148,000) over the same 10-year period, it would require the full upfront cost paid in full.

 

 

Intelli-Hood Creative Financing Return on Investment
A graph comparing Intelli-Hood Investments against creative financing

 

So, if your business is in a similar position where your budget is paused but you are still interested in saving energy, reducing greenhouse gasses, and cutting operating costs – maybe this creative financing can work for you, too. We can continue to work together to change the world one building at a time, all while exploring realistic options in the current economic climate.

Energy Efficiency & Renewable Energy: Fighting Climate Change with a One-Two Punch

To invest in energy efficiency or renewable energy? A question often pondered by building owners, design engineers, investors, energy engineers, performance contractors, and anyone in between who has a say deciding how to invest money to make the strongest financial and environmental impacts. In an ideal scenario, one can invest in both efficiency and renewable energy.

 

 

Integrating Efficiency and Renewable Energy

When it comes to the materials we use in everyday life, we have all heard the phrase “Reduce, Reuse, Recycle.” Well, there is a reason why reduction is mentioned first! It can be argued that the most sustainable energy source available is the energy that we never have to use.

Of course, there will always be energy used no matter how efficient a building is. But, in the energy spectrum, renewables reduce the cost for the electricity that must be used. Renewables also offer many other benefits, such as protection against fluctuating energy costs, incentives like federal tax credits, net metering, shaded parking lots… the list could keep going. And research confirms that investing in both energy efficiency options and renewable energy is a smart move. The American Council for an Energy-Efficient Economy (ACEEE) and the American Council on Renewable Energy (ACORE) collaborated in a 2007 study, reporting that investments in both energy efficiency and renewable energy are essential for the United States to create a secure energy future.

 

 

Boxing gloves

 

 

Creating an Energy Synergy

Think about it like this… If a boxer has a great right hook but a poor defense, he may win some fights but could easily lose to an opponent with a solid defense and a timely counterpunch. Combining two strengths to be stronger overall is called synergy. That is when the whole is greater than the sum of the parts. When energy efficiency and renewable energy are combined, they complement each other in a way that can maximize the total impact, both environmentally and economically. Consider this…

Right hook: An upgraded utility plan to reduce HVAC costs.

Left jab: Intelli-Hood®, Melink’s demand control kitchen ventilation system to further reduce HVAC costs.

And for the knock-out uppercut: A solar array made of super-efficient photovoltaic modules that meets the entire energy load of the building (taking into account the reduced energy usage from the previous energy efficiency measures).

And what’s even more of a win? By reducing the facility’s entire energy load, the upfront cost of the solar array is reduced. Plus, the quick payback as a result of the energy efficiency measures creates additional cashflow to help pay for a renewable energy source, like solar array (or even geothermal!).

 

 

Accounting for Energy Opponents

But what if? Let’s say that the uppercut was blocked in this scenario because, in many cases, the availability of renewable energy is limited due to geography and available space. For example, in the hills and valleys of Southern Ohio, wind energy is not going to be near as effective as compared to the plains of Northwest Texas.

Or, while solar performs well in Ohio, a building could have very limited space for an array. For the counterpunch here, one could implement new energy efficiency technologies and maximize efficiencies on existing equipment. Then, for the knockout, a smaller solar array like a parking canopy could still be very impactful.

The bottom line? There are many options at play when it comes to the powerful combo of energy efficiency and renewable energy. Together, this combo helps to reduce peak demand charges, which can be astronomically higher than off-peak charges. For example, if a new energy-efficient HVAC system is added to an office building, that building will still see high peak demand charges (although lower than before the upgrade) from the utility. However, capturing a renewable energy source, like wind or solar, can greatly reduce the impact of peak demand charges.

 

 

Renewable energy wind turbine power

 

 

Winning the Fight on Climate Change

In summary, combining energy efficiency and renewable energy delivers the greatest environmental and economic benefits. Melink Corporation can help building owners, engineers, and designers with both energy efficiency and renewable solutions. We know this combination works from experience, too. With our own Zero Energy Building and another LEED Platinum building, Melink does not just talk the talk, we walk the walk.

Contact us today to protect your business from the volatile energy market, commit to sustainability, reduce utility costs, and fight climate change.

A Day in the Life of a Melink Engineer

 

Engineers serve a variety of roles at Melink Corporation — application, project, tech support, product design, and field service. In honor of National Engineer Week (Feb 16-22, 2020), Melink employee-owners are sharing what they do. Read along in a day in the life of…

 

 

 

Tom Critchfield
Quality Engineer & Field Service Engineer

I am currently in a dual role at Melink. As a Quality Engineer, I typically wake up early and log on to our internal server to see the Test & Balance queue status. I’ll catch up on emails and have a check-in phone call with the Field Service Manager to see if there is anything urgent from the customer service team or field technicians. The rest of my day consists of reviewing submitted reports, providing feedback to technicians, and planning potential quality assurance audits for the following days or weeks. Depending on the day, I will also be involved in meetings and technician education programs.

Then, as a Field Service Engineer, a large chunk of my time is spent traveling and getting to the various T&B job sites. This includes driving, flying, and speaking with border agents to gain access to Canada. Once on site, I speak with the site superintendent, mechanical contractor, electrical contractor, and anyone else I’ll need to be working with to complete the job. This is followed by data collection and report construction. The rest of the time is just balance completion and finishing the report.

 

 

 

Josh Gerlock
Business Development Manager

With my engineering degree, I have become a technical sales consultant for Melink. I often start my day studying industry news and learning about the latest technology trends that my customers are following. From there, I check for any emails that came in the night before while I was not at work and take care of any pressing replies. Next, I move on to new projects by finalizing proposals and creating an energy analysis. The energy analysis is used to show our potential customers how much energy and money our Intelli-Hood® system can save them. On any given day I could be presenting the analysis to customers through a webinar or over the phone to help make sure they understand everything. Part of the day involves being reactive as well by fielding calls and answering customers’ questions. With products that are very technical, there are plenty of times I do not have all the answers, but I always know where to go to make sure I find them or connect my customers with someone who does. Almost three years in, I am still learning new things, so I am always on my toes!

 

 

 

Anna Rusconi
Account Engineer

The Account Engineer role at Melink varies from day to day from working with the customer to working with the technicians to collecting data analytics.  When we receive a Test & Balance quote request from one of our national accounts, I look through the mechanical prints to prepare a quote. The quote covers the scope of work for the visit, as well as the estimated time needed for an on-site technician. Before our technicians visit on site, I make sure they are equipped with all the information they need to successfully complete the job. If the technician has any questions while on site, I work with them and our site contacts to ensure the visit goes as smooth as possible. Once the T&B is completed and the final report is sent to the customer, I will work with the customer to help them understand the information.

Also, when we visit customers or have customers visit our office, we provide them with an overview of their project data from the previous years. I work with the National Account Manager to pull data to present to the customers. I really enjoy this position because each day is different, and it is rewarding to help the customers and the internal team.

 

 

 

Darren Witter
Vice President of Human Resources

Earlier in my career, I applied my engineering education to more “traditional” engineering vocations. These included product development, manufacturing, design, commissioning, and green building construction and operation. These experiences were incredibly valuable, and I enjoyed them immensely. Now, after more than two decades into my profession, I apply my engineering principles and training in other ways. Though different from what I first envisioned as an engineering student, these ways are equally exciting, challenging, and fun! I help fellow Melink employee-owners with career development by providing training on technical concepts, soft skills, company values, and lessons from my personal experience. I meet students and prospective employees and explain our unique company mission and culture, our products and services, and career opportunities.  I provide tours to visitors of Melink’s Zero-Energy headquarters, one of the greenest buildings on the planet, and inspire them to be more sustainable in their lives. I seek ways to improve processes and strengthen our businesses. And, most importantly, I help to care for our greatest asset at Melink… our employees. Years of solving technical problems as an engineer have helped prepare me to now solve business challenges, to guide and mentor others, and to make the world a better place!

 

 

 

Sarah Evans
Embedded Software Engineer

As an engineer at Melink, my job is to take the ideas for what we want PositiV® or Intelli-Hood® to do and implement them. Since I started working at Melink, my main focus has been on PositiV, our building health monitor system. My work includes programming the PositiV devices, maintaining an application for setting up the devices, collecting and analyzing data, and testing. While all these tasks involve software development, each problem is unique and can require a number of different solutions. Essentially, my day-to-day includes solving puzzles, which I really enjoy.

 

 


Want to be a Melink engineer? Check out our Careers page.

“We’ve Done Benchmarking. We’ve Done Lighting. What’s Next?!” Kitchen Ventilation.

The Benefits of DCKV

Kitchen ventilation, both exhaust and make up air, represent a significant opportunity for kWh and kBTU reductions in your facility. Demand Control Kitchen Ventilation, (DCKV) uses temperature and optic sensors to vary exhaust speed and make up air fans.  This is in response to precise cooking intensity underneath all kitchen hoods. With fans only running as needed, savings are gained on fan energy (controls produce 40-60% average fan speed versus 100% without controls). In addition, there are heating and cooling savings gained as a result of kitchens not evacuating all air that was just conditioned.

These controls can be installed in new construction projects. They’re usually specified by engineering firms in the design phase of your project, and should qualify for one LEED point. In addition, DCKV is a path to compliance for commercial buildings’ energy codes for states that have adopted ASHRAE 90.1 2010 and greater. You can see what your state’s requirements are here.

Retrofitting

Retrofitting the temperature and optic controls within existing kitchen exhaust hoods is equally effective at generating energy savings. It’s important to confirm that the controls are UL 710 and 2017 listed. This permits them to be installed in any manufacturer’s hood in any cooking application. There are many utility rebate incentive programs available for the installation of DCKV as well.

Kitchen Ventilation in Action

The financial impact for hospitals’ operating costs is significant when kitchen exhaust and makeup air fans no longer run at full speed 24/7.  A study by the EPA demonstrated that each dollar saved by a non-profit hospital, is the same as generating $20 in new revenues. Incidentally that same dollar saved in a for-profit facility is like increasing EPS by one penny.

Melink recently completed a Mid-West hospital project that produced $20,000 (per year) in combined savings. The savings included electrical, heating and cooling costs. Using EPA study metrics, this equivalates to $400,000 in new revenue for this facility.  Taking rebate incentives for our technology, the hospital’s ROI was less than one year.

The Purpose of DCKV

The goal of any DCKV project is to install controls that maximize the energy savings within the kitchen. In addition, DCKV will assist compliance with building energy codes, attain LEED points and make kitchens quieter and more comfortable. This article goes into greater detail and dives deeper into how these controls pay back initial investment. The articles recently appeared in the American Society for Healthcare Engineering publication, Inside ASHE.

Find the Inside ASHE article on kitchen ventilation here.

A LEED-Driven Remodel at the Cincinnati Zoo

Context

Base Camp Cafe at the Cincinnati Zoo was due for a remodel project in 2013 and took the opportunity to retrofit the restaurant with environmentally sustainable features. They set the goal of achieving LEED Gold certification, but meeting the requirements posed much challenge. Below are the restaurant kitchen conditions:

  • Total motor power: 10 HP
  • Daily operating hours: 14
  • Days per week: 7
  • Weeks per year: 52
  • Cost per kilowatt hour: $.10
  • Climate zone: 5
  • Customers per year: 1.4 million

 

Results

The Cincinnati Zoo Sustainability Team chose to install Intelli-Hood Controls to gain credits toward their pursuit of a LEED Gold-certified cafe. The Zoo previously worked with Melink for a solar canopy project. Since 2013, Base Camp Cafe has been ranked the greenest restaurant in the nation, as measured by The Green Restaurant Association. This association granted them 473 points for the different green elements of their restaurant, with their energy reduction accounting for 220 points, or 47% of their score.

 

Energy savings graphic

The following is a five day fan speed graph at the Base Camp cafe:

Green graphic

 

Here are a before (navy) and after (green) reductions in kilowatt hours, heat load and exhaust volume:

energy data before and after Intelli-Hood

 

The facilities team at the Cincinnati Zoo commented on their impression of Intelli-Hood and working with Melink:

“I appreciate that Intelli-Hood is automated, it’s one less thing to worry about in managing a restaurant. We don’t have to remind people to turn it on and off. We get savings by letting the system run on it’s on.”
– Tony James, Cincinnati Zoo, Facilities Management

 

“Melink was detail-oriented and, to be honest, a lot more on-the-ball than we were. They were responsive to the fine-tuning issues that came about, such as sensors getting dirty with grease.”
– Greg Speidel, HGC Construction, Project Manager

 

“Restaurants are huge energy hogs, it’s also where you can get your money back.”
– Mark Fisher, Cincinnati Zoo, Director of Sustainability

 

COULD INTELLI-HOOD BE A FIT FOR MY PROJECT?

Are you curious how much energy Intelli-Hood could save within your commercial or industrial kitchens?  Submit an energy savings estimate request form at the bottom of our Intelli-Hood page to get started.

EMAIL THIS CASE STUDY OR SHARE IT TO YOUR SOCIAL MEDIA BY CLICKING THE ICONS BELOW.

Air Balance Basics for Existing Facilities

We understand the concept of the “band-aid approach” whereby you find a quick cover-up to a problem without actually investigating the root of the it.  This concept applies frequently to Facility Managers or Building Owners wrestling with HVAC emergencies being caused by negative building pressure. They tackle issues such as condensation, hot/cold spots, humidity, odor, and difficult to open doors with “band-aids”. These “band-aids” are in the form of increased air conditioning, dehumidifiers, wet floor caution signs, door mechanisms, air fresheners, apologizing to patrons, comping customers’ bills, and so on.  This is understandable when you’re managing 80+ facilities, all with problems that stretch far beyond just HVAC.  However, it comes with a cost of spending a lot of time, money, energy, and reputation just to have the issues continuing to come back.  While balanced airflow is not a tangible product, the consequences of an unbalanced building are very perceptible.

Facility Managers are ready to de-mystify their HVAC issues by understanding the root causes.  Use the air balance basics below to recognize when an issue is airflow related.

What does it mean to have a balanced airflow?

Think of financial statements with income listed in one column and expenses in the other.  Much like a budget, you want incoming cash coming to be equal to or greater than cash going out. You typically want the air going into a building to be slightly greater than the air going out.  Similarly, think of a balanced scale.  In the graphic below, air is being drawn out of the building by exhaust fans at a rate of 4000 CFM (cubic feet per minute). This is to remove heat and smoke from kitchen cooking appliances and foul air from the restrooms. Air is also being introduced into the building through an outside air fan, at a rate of 4500 CFM. This is to provide fresh breathing air for the occupants and to replace the exhausted air.  The result is a slightly positive building pressure of 500 CFM (4500 – 4000 = 500), which signifies a balanced airflow.  Conversely, if air coming into the building is slightly less than the air leaving the building, then you have a negative building pressure, which is the frequent culprit of many HVAC problems.

Which brings us to a crucial pairing to the air balance concept.  That is if balanced airflow is peanut butter, then a performance test is the jelly.

What is an air test & balance service?
 

Air balance testing is the process of measuring HVAC airflow performance.  Once tested, the systems are then adjusted, or balanced, so the air brought into a building is slightly greater than the air being pulled out of the building.  The benefit for testing and balancing being a combined service is explained by Rob Falke, President of the National Comfort Institute, “This [positive] pressure condition can be designed, but to be sure it actually happens requires air diagnostic testing.  However, it’s hard to say how great the positive pressure reading in the building will be. It depends on how tight (or leaky) the envelope of the building is, and what other pressure generating forces exist, including the wind, appliances, exhaust fans, and the stack effect of the building.”  The result is a comfortable, healthy indoor environment with an HVAC system that is optimized to perform efficiently.

 Sources:

  • Digital image. Air Concepts LLC. N.p., n.d. Web.  Nov 25, 2015.
  • Falke, Rob. “How to Measure Building Pressures.” Contracting Business, 1 May 2006. Web. 25 Nov. 2015.