Healthy HVAC Equals Healthy Indoor Air Quality

By Shelly Morrison 

Isn't your work productivity affected by temperature, lighting, air quality or any other environmental conditions? The answer is, it is. Not only it has a real impact on your indoor activities, but it also affects your health optimally. HVAC systems provide ventilation and maintain pressure relationships between spaces of both domestic and commercial environments promoting safe and sound health of an individual. Regarding this, your heating, ventilating and air conditioning (HVAC) equals balance your home or office atmosphere by filtering the warm or cold air as needed. 

Failing to check HVAC systems regularly can be costly.

There are many all-in-all air conditioning companies which you should call their professionals for your HVAC repair in San Antonio. They will do a survey initially to inspect if any dust, pollen, dirt or debris circulating your surroundings and also check the building to find any leaks, mold spore is affecting the system. Other than these, especially asthma patients or people who have allergy problems can face severe health disorders if the vehicular environment comfort is not ensured. You must keep in check your HVAC technology annually or twice a year to make sure about indoor air quality. 

When In A Year You Should Check Your HVAC?

Before your city hits the cold weather which approaches the San Antonio, Texas in the fall usually, call local HVAC contractors based in San Antonio who are trusted for heating, cooling and air conditioning services and can regulate your environment through working on following factors:

Factors That Contribute to Healthy HVAC System Performance

• Temperature control, 

• Oxygen replenishment, 

• Removal of moisture, 

• Locating odors, smoke, heat, dust, 

• Finding airborne bacteria, carbon dioxide, and other gases.

To guarantee HVAC efficiency, there are multiple maintenance factors which contribute to healthy HVAC performance but in this time, master only these three factors and make your system runs properly.

1. System Size

System size plays an essential role in healthy HVAC performance. First, consider your home size and ask yourself if your system is too large or small for your home. In the case of too large, the system will waste its excessive power in starting up which can result in short cycling. Secondly, if the system is too short, it can also screw up your home or office HVAC conditions by not handling the load. The air conditioner or heater will take massive time to reach the thermostat's threshold. Both of the cases will end up wasting energy if the right size system is not installed. 

Contact HVAC professionals who can tell if you got poor system sizes and further diagnose whether or not your system fits the load requirement of your home.

2. Preventive Maintenance

Keep up regularly with preventive maintenance schedule to ensure if HVAC performance is doing well or whether it has the likelihood of failing. It is carried out when the equipment is working so that the professionals can then and there detect the downtime and improve on performance worthwhile. That's why you should have a preventive maintenance schedule similarly like a part of your health routine. Just like your body needs a regular health checkup by the doctor, your HVAC system also needs to get check its performance few times a year. Natural airing (ventilation) includes both the exchange of air to the outside as well as circulation of air within the building. It is one of the most important factors for maintaining acceptable indoor air quality in buildings as well in homes. 

Regular maintenance checkup involves testing the system's components and efficiency and fixing any problems encountered during the testing.

3. Indoor Air Quality

Air Quality Monitor

When a system is not cycled off, it leads to poor indoor air quality which makes your HVAC unit to perform even worse making it less energy efficient and consuming more power. Monitor your indoor air quality on a regular basis as it's the best way to promote healthy lifestyle for your family also making your HVAC system more efficient. 

You can also work it out a little by cleaning your indoor air handling units and outdoor compressors and removing the blockage. Check ducts for leaks, clean filters and more. This is a basic you can do to cause your system no-damage. If you fail at these checks, get mentally prepared for costly repairs.

There's another thing you can do which involves cleaning out the inside of your furnace. It will also help you with reducing your electric bills. If you're short of time and a workaholic, feel free to call experts who inspect the heat exchanger to verify there is no carbon monoxide leaking into your home or workplace.

At the end of the day, we advise you to tackle primary factors on your own and for the complex situations, you can call professionals for help to maintain your HVAC performance in a healthy way giving you more comfortable home and office with indoor quality environment.

For more details feel free to contact us:    https://www.beyerboys.com/residential/

Article Source: [http://EzineArticles.com/?Healthy-HVAC-Equals-Healthy-Indoor-Air-Quality&id=10098276] Healthy HVAC Equals Healthy Indoor Air Quality

6 Ways to Save Energy During Spring

The weather is getting warmer; it's time to pull out the grill, call the pool cleaner back, and get those gardening tools out of the basement. It's spring! But spring also means it's time to look at how you can save the most energy and the most money. 

Many Ways to Save

A lot of people can tolerate cold weather better than hot weather, which means, as the weather gets warmer and warmer, it will become increasingly difficult to fight the impulse to turn on the air conditioning and leave it on for hours. Fortunately, there are several things you can do to help keep your home cool without running up your energy bill.

Take it easy on the thermostat:

Set the temperature as high as you can while still being comfortable. The smaller the difference between the indoor and outdoor temperatures, the lower your bill will be. Keep the house warmer than usual when you are away, cool when you get home. Set "Away" and "Home" temperatures easily with a programmable thermostat.
 

Image: Wikipedia

Keep in mind: Your house will not cool any faster if you set the thermostat to a colder temperature than usual. In fact, this will likely result in unnecessary expense and excessive strain on the cooling system.

Make the most out of your windows:

Prevent heat from getting in through the windows by installing window coverings such as blinds (interior and/or exterior), awnings, high-reflective films, draperies, shades, insulated panels, and shutters. If you live in an area where it cools off at night, turn of your air conditioning and open your windows while you sleep. When you wake up, shut the windows and blinds to keep the cool air in, unless there's still a cool breeze. You can still get some good cool air into the house in the early morning before the sun starts hitting your house/yard.

Turn on those ceiling fans:

By using your ceiling fans in combination with air conditioning, you can actually set the thermostat four degrees higher but remember that fans cool people, not rooms. If you leave a room, turn off the fan. Turn on your bathroom fan when taking a shower or bath to remove the humidity and heat.

 

Drop the water temperature:

Your water heater uses 18 percent of your home's energy-use. Turn the temperature down to 120 degrees F.

Minimize appliance-use and artificial lighting:

Using the oven on hot days will make the house warmer and subsequently more difficult to cool. Stick to the stove, microwave, or grill outside. Minimize using a computer or TV, running the dishwasher, or using hot devices like hair dryers. Install efficient lighting that doesn't release much heat.

Seal leaks to keep the hot air out:

Seal cracks to keep warm out from leaking into the house. Add weatherstripping or caulk to seal leaky windows and doors.

 

Better for the Environment, Better for You

Ultimately, anything we can do to save energy and conserve natural resources will benefit all of us, both directly in terms of personal cost-savings and indirectly in preserving our world for the future. At Vosh, we are committed to doing our part for the greater good, which is why our car washers use less than three gallons of water for each wash. Additionally, we offer waterless car washes.


To learn more about us or to download the Vosh on-demand car was app, visit our website at [http://vosh.me/]http://vosh.me/.

Article Source: [http://EzineArticles.com/?6-Ways-to-Save-Energy-During-Spring&id=9676317] 6 Ways to Save Energy During Spring.

New Thermal Bridging Guide Provides Solutions for Energy Efficient Homes

Solar Umbrella002 (Photo credit: Wikipedia)

Morrison Hershfield announced last week that the book Building Envelope Thermal Bridging Guide – Analysis, Applications, and Insights is now public and can be downloaded. The guide aims to overcome obstacles confronting the industry with respect to mitigating thermal bridging to reduce energy consumption in buildings.

According to the guide, “thermal bridging is caused by highly conductive elements that penetrate the thermal insulation and/or misaligned planes of thermal insulation. These paths allow heat flow to bypass the insulating layer, and reduce the effectiveness of the insulation.”

The Guide was developed by engineering firm Morrison Hershfield in collaboration with co-sponsors and industry partners.  Co-sponsors include BC Hydro Power Smart, Canadian Wood Council, Fortis BC, FPInnovations and Homeowner Protection Office (a branch of BC Housing).  Industry partners helped extend the scope of the guide to include many additional details.

The principle goal of these collaborating organizations is to promote energy-efficiency in buildings by increasing awareness of the impact of and methods to mitigate thermal bridging.  To meet these goals, the Guide addresses a number of obstacles currently confronting our industry by:

1. Cataloging the thermal performance of common building envelope assemblies and interface details.
2. Providing data driven guidance that will make it easier for the industry to comprehensively consider thermal bridging in building codes and bylaws, design and whole building energy simulations.
3. Examining the costs associated with improving the thermal performance of opaque building envelope assemblies and interface details, and forecasting the energy impact for several building types and climates.
4. Evaluating the cost effectiveness of improving the building envelope through more thermally efficient assemblies, interface details and varying insulation levels.

The Guide, which is broken into three main sections for ease of use, contains helpful information for technical committees for energy standards, regulators, utilities, architects, mechanical designers, building envelope consultants, energy modellers, developers, manufacturers and trade organizations.

The Building Envelope Thermal Analysis (BETA) Guide outlines how to effectively account for thermal bridging and is backed up by an extensive catalog of thermal performance data.  This information is essential for practitioners evaluating building envelope thermal performance.
Researchers and regulators will be interested in the sections focused on market transformation, which includes an evaluation of cost effectiveness and energy savings in common large building types.


Original article: Green Building Elements with materials from: PR Newswire.
Image: BC Hydro
 

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New Living

Image by brunosan via Flickr

The Texas flag flies in Houston.

A green building store in the Lone Star State shows how to build a healthy home, and a good business too.
 

Recently, I received a visit from my cousin Amanda Claire DeMers of Houston, who was in Philadelphia to see some of our great historic sites. I've known that she's been involved with the acclaimed store, New Living, which is an eco-smart, green building hub for Houston's sustainability sphere, and a certified "B" corporation. So after a little family catch-up chat at Johnny Brenda's restaurant and pub here in the Fishtown neighborhood of Philly, we discussed some of the innovative work that she and the store has been doing back in her hometown.


How long have you worked for New Living?

I have been at New living for two months, but New Living has been around for two years. I came in with a background in environmental policy, my Master's was on fisheries management, so completely not to do with design or retail or marketing or anything like that. But I met the owners and we got along. I came on and have been working retail there for the past couple months, but I'll be doing some PR and marketing for them - press releases and such, social media maintenance, and then a lot of events in environmental education.

Tell us about New Living - what they do, their history.

New living is a store in Houston and their niche is healthy green building and home. They sell all kinds of home-building products, like counter-tops, flooring, and they also sell organic mattresses and bedding. And then next door, which is actually part of our store but has a different storefront, is a shop called The Green Painter. That opened up six or seven month ago as a split off from New Living, and they sell no-VOC paints, non-toxic glues, wood stains, and concrete stains.

So all of our products are non-toxic and they're all environmentally friendly. But a lot of the emphasis is on the non-toxic. Much of that, to some degree, is because Houston hasn't necessarily been a very green conscious city, and when New Living moved in they thought they were going to be this sort of green store with a straight environmental message. Houston wasn't as responsive to that message as they envisioned, so they started learning more about indoor air quality and health and promoted those ideas, which sometimes goes along with environmental certifications like LEED, though sometimes it's independent. In fact, sometimes it's the opposite - a lot of LEED certification buildings trap the air inside, so they've really embraced the non-toxic banner and it seems to have resonated well.

You bring up a good point. As a trained energy auditor, my focus is often on sealing the "envelope of the home" to improve energy efficiency. We check for high CO levels in furnaces, mold, lead paint, asbestos, pet dander and other potential indoor air quality threats, but there are a multitude of contaminants to consider. We have to be very conscious of toxins as we tighten up homes.

Image by Scoobyfoo via Flickr

Non-toxic materials

Yes, and we can start that by not bringing as many toxins into the building process, which is the significance for having  formaldehyde-free flooring, and surfaces that are antimicrobial and naturally bacterial resistant and don't contain chemical dyes, and wool carpets that don't contain synthetic coatings on them. When you don't bring these toxins into the home to begin with, you start at a much easier place. Then you can begin to manage it with something like an air filter, either for a whole home or maybe just one room. We also sell air filters and water purifying systems.

It seems like it takes more than just standard marketing and offering healthy green products to make your business thrive. You've moved into channels of New Media to advocate your concept. Tell us more about the advocacy side.
  
They've always done pretty well as a business, because, for whatever reasons, Houston as a city is doing well. So we do have customers that have the money to spend on quality home products. The key is making sure we educate people about why our products are the better choice. And there will be a greater role for the educational and advocacy component through time.

We're actually not just a store, we're a certified "B" corporation or benefit corporation, which is a certain way that we're chartered to serve the long term interests of the shareholders and to help solve social, economic and environmental problems, rather than just immediate returns to investors.

Image by ooh_food via Flickr

So this falls in line with business concepts that have been described as an emerging new economic model: A business that's sustainable and socially responsible, but profitable too.

Certain states already have programs in place that to certify and encourage B corporations. And hopefully, someday, it would be nice if there was some sort of tax advantage too. So say, instead of being a non-profit or, well, an oil corporation - somewhere between BP and Oxfam - we could find a place where we received some government benefit of taking on these problems.

Aside from providing non-toxic home products and educational outreach, what other services does New Living offer? Do you work directly with contractors?

Yes, and that's something that's really cool about our business. Downstairs is the store and showroom, but upstairs is sort of this green business incubator, where we have several green designers, an urban renewal realty program, green architects, and a solar company. It's really a hub of green activity in Houston and we've worked hard together to make a green scene here.

That's interesting. Houston doesn't come to mind as top on the list of cities with a strong sustainability community, like say here in Philly, where our mayor has been pushing to make this the greenest city in the nation. How would you compare Houston to others?

Bill McKibben. Image: Wikipedia

Some people say that it's behind major cities, but it's caught up pretty fast. Because we have some money here, it's been able to escalate more quickly.

Actually, one of our main customer components is moms. Sometimes even mom's who's husbands work for a big oil company or in the chemical industry, but they've read some of the popular Michael Pollan, Bill McKibben type books and they're saying "you know, I don't want to bring bad things into my home." Just like the local foods and organic foods movement caught on big partly because moms were afraid of what they were feeding their kids, we're hoping that non-toxic mattresses and organic flooring will follow.

I hope so too. Thanks for stopping by and giving a word to our readers about New Living and your great city. I hope you were able to take in some of the famous sites here as well.--D.A DeMers.

For more information about New Living and to read some of Amanda's informative blogs, visit their expansive website at www.newliving.net.

Coming soon on Home Science: An innovative Philly compost company has been hittin' the streets hauling away stinky stuff from restaurants and supermarkets. Now they're making house calls. Pretty awesome idea, don't you think? (You don't have to answer, just trust us).

 

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Breathing Room

  
I am one of millions of Americans who suffers from asthma. Most of the time, I don't think about it. I go on with my day like everyone else. Every so often, though, I have a little trouble breathing. In the worst case, I'll have an attack.

Air Quality Index, EPA. Image: Wikipedia

It's sometimes hard to explain to people what it feels like when you get an asthma attack. Many non-asthmatics liken the condition to a typical respiratory affliction, like clogged sinuses or a cough. It's not. An asthma attack feels like you're suffocating. Think about it - air is about the most immediate thing we need to survive. If your lungs swell up and keep you from breathing, that's about as scary a feeling you can have.

Thankfully, the EPA has provided some helpful seasonal information that can help prevent asthma triggers:

Asthma rescue inhaler.

Summer heat is here, and that means it is more important than ever for people with asthma or other respiratory ailments to pay close attention to the air quality where they live. Like the weather, air quality can change from day to day or even hour to hour.

During the summer when ozone levels rise, the number of people with asthma related symptoms admitted to hospitals and emergency rooms increases.  Asthma rates – especially among children – have increased dramatically.  Asthma affects 25 million people in the United States, including seven million children. That’s 8 percent of the population. One out of every 10 school aged children is affected.

“While we have made great strides in improving air quality, we still need to do more,” said EPA mid-Atlantic Regional Administrator Shawn M. Garvin. “By further improving air quality, we can help to control asthma and provide a more active lifestyle for children, a vulnerable population.”
 

In addition to the essential step of speaking about asthma with your health care provider and being aware of general air quality conditions, the EPA list the following specific steps that can help prevent an asthma episode:
   

• Play it safe. Ground-level ozone and particle pollution can exacerbate an asthma episode. Look for the Air Quality Index (AQI) during the local weather report or go to EPA’s website www.airnow.gov. The Air Quality Index uses a color-coded system to display whether the five major air pollutants exceed air quality standards for the day. When the Air Quality Index reports unhealthy levels, people, particularly asthmatics and others with respiratory ailments, should limit strenuous outdoor activities.

• Don’t smoke in the home. Take it outside. One of the most common asthma triggers in the home is second- hand smoke. Take the EPA ‘smoke-free home’ pledge: www.epa.gov/smokefree.

• Break the mold. Mold is another asthma trigger. The key to controlling mold is controlling moisture. Wash and dry hard surfaces to prevent and remove mold. Remove, and if possible replace, moldy ceiling tiles and carpet. For more see EPA’s website: www.epa.gov/asthma/molds.

 

Asthma doesn't have to be debilitating. To the contrary, you'd be surprised how many people in your workplace or social settings likely have the condition. With proper consultations by a healthcare professional, and by taking a few steps to understand the science of air quality in your home and addressing possible triggers, asthmatics can be as healthy and productive as anyone - perhaps even more!--D.A DeMers.

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In the Company of Men

Image: D.A. DeMers

To be honest, I was hesitant about writing this story. The thought of interviewing a person from a big energy company seemed odd, considering my scribbling is usually about ways to limit energy use. As a clean energy advocate, my rebel impulse has often been to fight the Power, and from all my preconceptions, a city's gas company seemed like the consummate example of, well, The Man.

Or perhaps The Woman.

Stop there, because when I met Marlynn Jannett, a pipe mapping designer I interviewed from Philadelphia Gas Works, my concerns were essentially set to rest.

Her story is one of guts and determination - the American dream exemplified, and a friendly face for the gas company. She's also my neighbor.

Ms. Janett began her career with Philadelphia Gas Works a couple decades ago. She was the first woman hired to work in field services for the company. Her current position involves creating CAD designs of gas pipes for "prudent mains" where the risk of breakage is possible, or in the worst case, has already occurred.

Image by osde8info via FlickrThe gas company is on a constant schedule to replace antiquated pipes, such as those made of cast iron, with newer materials like PVC that are less corrosive and more ductile. In a city as old as Philadelphia, upgrading such infrastructure can be extremely challenging, considering the maps provided are often outdated or nonexistent. Their efforts often include exploratory excavation measures such as drilling through cement foundations.

But the biggest initial challenge for Ms Janett's career was to break through the so called glass ceiling.

Her training came by way of a unique outreach program from the Private Industry Council developed to provide women with engineering skills needed to facilitate their advance into the industrial workforce - a workforce completely dominated by men.

"This all came to me a bit by accident," she said. "I was working in the billing department of a legal firm when I got laid off. Then I heard about the PIC program and thought 'why not?'"

Marlynn Janett

After showing an exceptional ability to master a variety of CAD software programs, she was visited by two engineers from PGW. A lengthy recruitment process ensued, until the company determined she possessed the necessary aptitude for the job. She out-competed several male candidates with her sharp skills and astute interviews, and planted herself firmly in a solid career.

"Some guys weren't too happy at the time, but they got used it," she acknowledged, when asked if she sensed resentment by her male counterparts.

Now, a master of her trade, she's moved well beyond the issues of those days. They were simply milestones of an evolving culture. The only concern she has presently at her job is "working in the middle of Frankford Ave, lifting a manhole cover, and trying not to get run over by a car."--D.A. DeMers.


A Clean Energy Plan with the Community.

PGW recently introduced a number of green energy programs that intersect with various sectors of Philadelphia's business and residential communities. Their EnergySense program is made up of several initiatives that strive to help the company’s residential, commercial and industrial customers conserve energy and save money. It's also expected to create as many as 1,000 new local jobs, reduce the region’s carbon dioxide emissions by 1.24 million tons - the equivalent of taking 200,000 cars off Philadelphia’s streets - and support the Mayor's Office of Sustainability's Greenworks plan to make Philadelphia the greenest city in America.

Energy outreach at the NKCDC. Image: D.A DeMers

The plan involves connecting with a consortium of non-profit energy groups, neighborhood organizations, and city departments to provide initiatives such as the The Enhanced Low Income Retrofit Program, Residential Heating Equipment Rebates, Commercial and Industrial Retrofit Incentives, Commercial and Industrial Equipment Rebates, High Efficiency Construction Incentives, and Comprehensive Residential Incentives.

Over the next five years, the company plans to invest $60 million to generate over $110 million in net savings for all of PGW’s customers. Saving money while saving the planet? Sounds like a win-win solution for everybody.--D.A. DeMers.

More info regarding PGW's programs can be found at www.pgworks.com. Plans administered by the Mayor's Office of Sustainability can be found at www.phila.gov/green.

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Sealing the Envelope

         

Home Energy magazine. Source: Flicker

Sealing the envelope of the home is at the core of weatherization and home energy science. Before moving on to more advanced measures in green-building, air sealing and insulating the thermal boundary of a home must first be achieved. The US Department of Energy, through its Energy Efficiency and Renewable Energy office, recently published some very useful information regarding these essential weatherization tactics on their Energy Saver's blog (shown below). 

Weatherization and energy efficiency in homes and other buildings has become a significant area of study and concern as energy rates continue to soar, and the depletion of natural resources and degradation of the environment remains considerably problematic. Weatherization programs are in place throughout many states, in both private and public sectors, and retrofit installers, crew chiefs, and energy auditors are rapidly becoming fast-track career fields in the home-building trades.--D.A DeMers

Your Home

Air leakage, or infiltration, occurs when outside air enters a house uncontrollably through cracks and openings. Properly air sealing such cracks and openings in your home can significantly reduce heating and cooling costs, improve building durability, and create a healthier indoor environment.

It is unwise to rely on air leakage for ventilation because it can't be controlled. During cold or windy weather, too much air may enter the house. When it's warmer and less windy, not enough air may enter. Air infiltration also can contribute to problems with moisture control. Moldy and dusty air can enter a leaky house through such areas as attics or foundations. This air in the house could cause health problems.

The recommended strategy in both new and old homes is to reduce air leakage as much as possible and to provide controlled ventilation as needed.

For more information from the Department of Energy, see the following resources:

• Air Sealing an Existing Home
• Air Sealing for New Home Construction

Note that air sealing alone can't replace the need for proper insulation throughout your home, which is needed to reduce heat flow.

-------------------------------------------------------------


In addition to the DOE's air sealing article above, here are some insights I've included on insulation issues for specific climates, as well as other weatherization related situations:

Climate Map of the US. Source: Google Maps

Cold Climates

In cold conditions, the main aim is to reduce heat flow out of the building. The components of the building envelope - windows, doors, roofs, walls, and air infiltration barriers are all important sources of heat loss; in an otherwise well insulated home, windows will then become an important source of heat transfer. Heat loss can be reduced by good weatherization, bulk insulation, and minimizing the amount of the building's non-insulative glazing. Some insulated glazing systems can greatly increase R-values, the industry's measure of thermal resistance.

Hot Climates

In hot conditions, the greatest source of heat energy is solar radiation. This can enter buildings directly through windows or it can heat the building shell to a higher temperature than the ambient air, increasing the heat transfer through the building envelope. The process is called solar heat gain, a measure of heat transmittance via sunlight in a home. 

Central Air Conditioners. Source: GNU 

Solar gain can be reduced by adequate shading from the sun, light colored roofing, heat-reflective paints and coatings and various types of insulation. Specially coated glazing can reduce SHG to around 10%. Thermal insulation is material specifically designed to reduce the flow of heat by limiting conduction, convection, or both.

Radiant barriers are materials which reflect radiation and therefore reduce the flow of heat from radiation sources. Good insulators are not necessarily good radiant barriers, and vice versa. Metal, for instance, is an excellent reflector and poor insulator. Radiant barriers are highly effective for attic spaces in hot climates. In this application, they are much more effective in hot climates than cold climates. For downward heat flow, convection is weak and radiation dominates heat transfer across an air space. Likewise, radiant barriers must face an adequate air-gap to be effective for the rest of the envelope.

If air-conditioning is utilized in a home in a hot, humid climate, then it is particularly important to seal the building envelope. Dehumidification of humid air infiltration can waste significant energy. On the other hand, some building designs are based on effective cross-ventilation instead of air-conditioning to provide convective cooling from prevailing breezes.

Building Envelope

The thermal envelope defines the conditioned or living space in a house. The attic, basement, or any porches may or may not be included in this area. Reducing airflow from inside to outside, or "tightening the envelope," can help to reduce convective heat transfer significantly.

The less natural airflow into a building, the more mechanical ventilation will be required to support human comfort. High humidity can be a significant issue associated with lack of airflow, causing condensation, rotting construction materials, and encouraging microbial growth such as mold and bacteria. Moisture can also drastically reduce the effectiveness of insulation by creating a thermal bypass.

Thermal Bypass

Thermal bypasses or "bridges" are points in the building envelope that allow heat conduction to occur. Since heat flows through the path of least resistance, thermal bridges can cause reduced energy efficiency. A thermal bypass is created when materials create a continuous path across a temperature difference, in which the heat flow is not interrupted by thermal insulation. Common building materials that are poor insulators include glass and metal.

A building design may have limited capacity for insulation in some areas of the structure. A common construction design is based on stud walls, in which thermal bypasses are common in wood or steel studs and joists, which are typically fastened with metal. Notable areas that most commonly lack sufficient insulation are the corners of buildings, kneewall in attic spaces, chimney chase-ways and voided areas where insulation has been removed or displaced to make room for system infrastructure, such as electrical boxes, plumbing, fire alarm equipment. Utilizing proper insulating materials for such spots or limiting the cross-sections can minimize the bypass.

 

Materials

 

Insulation Matthew Bisanz

There are essentially two types of building insulation - Bulk Insulation and Reflective Insulation. Most buildings use a combination of both types to make up a total building insulation system. The type of insulation used is matched to create maximum resistance to each of the three forms of building heat transfer - Conduction, Convection, and Radiation.

Bulk insulators block conductive heat transfer and convective flow either into or out of a building. The denser a material is, the better it will conduct heat. Because air has such low density, air is a very poor conductor and therefore makes a good insulator. 

Insulation materials to resist conductive heat transfer, or radiant barriers (see above), use air spaces between fibers, inside foam or plastic bubbles and in building cavities like the attic. This is beneficial in an actively cooled or heated building, but can be a liability in a passively cooled building where proper provisions for cooling by ventilation or radiation are needed.

Some radiant barriers are particular to specific spectral frequencies and will, for example, reduce the flow of infra-red radiation in comparison to other wavelengths.

Likewise, low-emissivity windows will transmit light and short-wave infra-red energy into a building but reflect back the long-wave infra-red radiation generated by interior furnishings. Similarly, special heat-reflective paints are able to reflect more heat than visible light, or vice-versa.

Thermal emissivity values probably best reflect the effectiveness of radiant barriers. Some manufacturers give an equivalent R-value for these products. However, these numbers are sometimes difficult to decipher, since R-value testing measures total heat loss in a lab and does not necessarily include situations involving radiation, conduction, or convection.--D.A DeMers (in collaboration with documented sources).

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