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By Mike Tonsbeek

Many building interior moisture intrusion issues are attributed to sheet metal failures. The primary cause for this condition is failed caulking joints. There are several reasons why these joints fail, such as inadequate attachment to the sheet metal components to adjoining surfaces such as walls, chimneys and other vertical or horizontal surfaces. Inadequate attachment relies on the caulking to keep these areas attached to each other or to surface they are mounted to, thus stressing the caulk beyond its limitations that it was intended to perform to.

Another reason that caulking joints fail is due to the application of the caulk itself. In many instances the sheet metal joints are surface sealed. This condition leaves the caulk exposed to the elements; this accelerates the deterioration of the caulk. Thermal expansion and contraction of sheet metal components and adjoining surfaces will also stress caulking beyond its limitation when only applied to the exterior surface of the joints.

For sheet metal components to perform in a satisfactory manner they must be properly lapped with caulk in between the joints, provided with proper attachment methods to the surfaces they are mounted to with acceptable interfacing to exterior cladding systems of the structure.

In some instances caulk must be applied in an exposed manner such when installing counter-flashing systems to masonry or structural concrete. With this type of application, the exposed caulking should be inspected periodically by a qualified waterproofing professional to make sure that caulking is performing as intended and to maintain the waterproofing integrity of the structure.

Last week the Dallas HBA's two-day seminar for "Green Building for Building Professionals" was a packed house of builders, suppliers, city planners, and designers.  It was exciting to have a large turnout to learn about sustainable home construction however, there was resistance to acknowledge the feasibility of making these changes with their customers.  While I have attended HBA classes across north Texas as a title sponsor, this was a more valuable forum for the readiness of the Dallas market.  Our instructor was Armando Cobo of Albuquerque, NM who recently became a Texan.  The stagnant market rendered it their loss and our gain.  Armando has designed and/or built over 300 sustainable homes.  As a founding member of Build Green New Mexico, he immediately became involved in Green Built Texas and the HBA to spread his knowledge of building green and what it takes to get there.

While we covered everything from the many elements affecting indoor air quality to analyzing the life cycle costs to the consumer, I could not help but notice the disconnect between an expert from New Mexico and successful builders from all over north Texas.  Many had gotten their feet wet but were not practicing the whole building approach of green building. Although there was some resistance at first, it became a bit of a fireside chat as to pragmatically find solutions.  Most builders expressed that their customers would not pay for a higher upfront cost even if they received a return on their investment in a few years.  Some even dismissed that certain methods were possible to implement and be competitive.  Several expressed distrust that architects know enough to properly detail the drawings and doubt that subcontractors were reliable to go the extra mile.  One began to get a feel for the temperature of the building market.  Especially in tough economic times,  many feared loosing jobs to a low bidder because the customer does not see the value in green building.  All in attendance were aware of the pending change but deferring to act.  Those that don't invest in learning new technologies are probably the ones that don't go the extra mile to assure quality control on your project.

My personal take-away from this forum is the need for more demand.  Homeowners are going to have to demand it from their builders and architects, builders are going to have to demand it from their architects and subcontractors, and we all are going to have to demand it from our government and suppliers.  This is a vast, quickly changing industry and no one has the full circle of knowledge.  We need to bury our pride and ask questions because "green" is not going away.  It will be trial and error for a while but if you are not taking the extra time in this slow economy to educate yourself and better your business, you REALLY won't have the time when things pick up.  The sooner you bring on a knowledgeable team of contractors, the more fluid, timely, and high quality your project will be.  Don't wait until your house is designed to select a lot and don't wait until your HVAC system is designed to selected an engineer.  Pick one area of sustainable design and really do your research.  Take the things you learned and test your current or prospective business partners.  For example, if your builder has never used a HERS rater on their jobs, any advanced mechanical systems may be useless and could nullify other efforts.  Don't know what a HERS rater is?  Well, I think you have just found your first topic of research.

10 Things You Should Know About Finding the Right Green Building Team

1. Building green does not have to cost more but less educated builders and contractors always cost more.
2. You do not have to be held captive to the limited knowledge of your subcontractors. The one paying should always have the upper hand.
3. Architects are not always educated on current techniques but are valuable as they act as another check and balance as well as a coordinator on projects.
4. It is usually better to not do anything at all than to do sustainability half way or incorrect.
5. Use resources such as the Dallas Residential Green Building Checklist,  the City of Dallas Green Building Guidebook,  and the NAHB Green Building Guidelines
6. Use third party inspectors, designers, and verifiers where possible.  It protects builders and homeowners from false claims.
7. Select a full team upfront.  No trade is educated enough to consider all things outside their specialty.
8. Life cycle analysis is done throughout all investments in your life, home construction should not be an exception.
9. Internet, Internet, Internet.  Every smart consumer should have a Minor in Google.
10. Every large green program started from a small community organization.  Let your voice be heard.

Germicidal lamps work along side other indoor air filtration systems to keep your indoor air quality healthy. The lamp uses intense rays of ultraviolet light to kill and control things like bacteria and mold that grow inside your home.  Research has shown that the air in your home may be up to five times more polluted than the air outside and considering how much time we spend in our homes we should do everything possible to make sure the air we are breathing is clean. 

How do germicidal lamps work?The lamp uses the short wavelength of UV that is damaging to forms of life at the micro-organic level. The light  penetrates the cell walls of the micro-organisms, which includes pathogens, viruses and mold,  so their DNA is disrupted causing them to no longer be able to grow or multiply. The lamp is installed in the air-duct system and sterilizes the air coming into your home. You will want to talk to your H.V.A.C. contractor about the size and the wattage of the lamp to be used in your home. The lamps are similar to a fluorescent lamp in that they do not produce much heat. Germicidal lamps do not produce any dangers to humans. Obviously, at high levels UV light can be damaging to humans but because of the low levels of light and of where the lamp is installed in the home the homeowner rarely comes in contact with the lamp. 

Once the lamp is installed it is usually good for close to 10,000 hours of continuous use. It is recommended that the lamp be replaced once a year. The lamp will most likely always be lit but the UV effectiveness of the lamp is reduced after about 10,000 hours of use. If you want the lamp to continually be effective then you do not want to wait until the bulb goes out to replace it. It is also a good idea to clean the lamp every few months. If you have a service contract with your H.V.A.C. company they will be able to clean the lamp during their quarterly visits. Making sure the lamp is clean is another way to help maximize the life of the lamp. Many companies also offer a warranty on certain components and so if something does go wrong it is many times covered under warranty. 

Using UV Germicidal Lighting as a way to sterilize air and water has been around since the mid-20th century. They are most often used in water tanks, sealed rooms and forced air systems. Many times you will see them installed in someone's hot tub or fish tank.  Germicidal lamps are not only  beneficial for humans but also for the performance of your home's heating and air conditioning systems. The contaminants that the lamp kills also have a negative impact on your indoor air equipment. Therefore the lamps not only have health benefits but also benefit the equipment in your home. 

Weather you are living in a newly built home or an older one you and your family are at risk of suffering from poor indooor air qulaity. There are three types of contaminants that can cause the air quality in your home to be poor. First there are particles which include things like pet dander, pollen and dust, and then airborne mold spores which are microscopic living organisims that grow and reproduce in warm, humid places and last there are odors and chemicals which include things like cleaning supplies, paints, and pet odors. If you are in a new home there is a higher likelihood of chemicals and in an older home you are at more of a risk for mold and mildew. There are many different air purification systems on the market. We use and recommend the Lennox PureAir Air Purification System. The PureAir system helps reduce the amount of everything from dust mites and mold spores to infectious bacteria and viruses. It is also one of the only indoor air quality systems that safely removes and destroys odors and chemical vapors. The PureAir Air Purification System is made up of three different parts. A MERV 16 Precision Pleat filter, two 55-watt UVA lamps and a metal insert that is coated with a catalyst that’s activated by UVA light. The system reduces concentrations of pollutants through a process called photocatalytic oxidation which combines three powerful air purfiiers. The filter captures particles and bioaerosols, removing them from the airstream, then as the chemical and odor filled airstrem flows over the UVA lamps, the airstream is exposed to the catalytic surface and then the light energy and water vapor in the air activate the titanium dioxide catalyst, which generates hydroxyl radicals. These hydroxyl radicals attack the carbon compenents of the odors and chemical vapors, breaking them down into carbon dioxide and water. Bad indoor air quality can effect the health of you and your family. The more odors and chemical vapors that are in your home the more likely you or a family member might suffer from shortness of breath or diziness, especially if there is already an underlying ailment such as asthma. It is beneficial for everyone in your home to breathe good quality air. The benefits of installing a Lennox PureAir Air Purification System include not only cleanliness and comfort but most importantly the health of you and your family.

What is ponding water?  Ponding water as defined by the NRCA, National Roofing Contractors Association, as water that remains on a roof surface longer than 48 hours after the termination of the most recent rain event.

Long-term ponding water on a roof surface is one of the most destructive conditions that can adversely affect the life cycle of a flat roof system.  The UBC, Uniform Building Code, and the IBC, International Building Code, require that a flat roof surface deck is provided with a minimal sloping of ¼” per foot for proper roof drainage.  Most buildings are built with that requirement, however, while this sloping is provided at the building framing stage some sloping is lost when the with the adding of additional construction components that typically are suspended from roof joists or trusses such as ceiling, plumbing and electrical systems. Heavy roof top equipment such as HVAC, refrigeration and air circulation systems may also contribute to loss of sloping to the roof deck.

There are several methods of correcting water ponding issues on a flat roof.  The most effective is to provide proper sloping with tapered insulation or re-decking with rip-strip framing.  For moderate to severe localized ponding, layering additional roofing membrane can produce limited success, however, care must be exercised not to just to move the ponding issue to another location of the roof.  Another method to correct moderate to severe ponding, is installing an additional surface drain recessed in to a sump box at the deepest point of the ponding.  This method requires the enlistment of a plumbing contractor for feasibility and installation of a drainpipe to the exterior of the building.

Most roofing material manufacturers will void their product warranties when ponding water conditions exist.  There are a limited type of roofing systems were ponding water does not affect the roof system life cycle or manufacturers warranties. The use of these systems should always be explored.

One should always consult with a qualified professional roofing contractor when dealing with ponding water conditions on a roof.   Budget restraints may leave both the building owner and roofing contractor with limited options on the decision to choose the lesser of two evils in choosing the better solution to the condition.

MT

As I was looking on the web for some information about bottled water, I stumbled on to this article. I feel that there is a bit more to building a green project, than products or services. I believe its a “Life Style.”  Wanting to do our part as individuals, check out this article below, and you will see why!  It might just make you think twice about “Bottled Water.”

Last year Americans spent nearly $11 billion on over 8 billion gallons of bottled water, and then tossed over 22 billion empty plastic bottles in the trash. In bottle production alone, the more than 70 million bottles of water consumed each day in the U.S. drain 1.5 million barrels of oil over the course of one year.

Ban The Bottle

Though the sale and consumption of bottled water is still on the rise, certain policy makers and activists have taken steps to reduce it. San Francisco Mayor Gavin Newsom signed an executive order in June that bars city government from using city money to supply municipal workers with bottled water, and New York City, where residents consume nearly 28 gallons of bottled water each year, launched an ad campaign encouraging residents and tourists to forego the bottled beverage for the city’s tap, long considered some of the best water in the country. Even upscale eateries in Boston, New York and San Francisco have taken bottled water off the menu, offering filtered tap instead.
Improve Your Health
Not only does bottled water contribute to excessive waste, but it costs us a thousand times more than water from our faucet at home, and it is, in fact, no safer or cleaner. “The bottled water industry spends millions of dollars a year to convince us that their product is somehow safer or healthier than tap water, when in fact that’s just not true,” says Victoria Kaplan, senior organizer with Food and Water Watch, a nonprofit that recently launched a Take Back the Tap campaign to get consumers to ditch bottled water. “As much as 40 percent of bottled water started out as the same tap water that we get at home,” she adds. A 1999 Natural Resources Defense Council study found that, with required quarterly testing, tap water may even be of a higher quality than bottled, which is only tested annually.

Water aside, the plastic used in single use bottles can pose more of a contamination threat than the water. A safe plastic if used only once, #1 polyethylene terephthalate (PET or PETE) is the most common resin used in disposable bottles. However, as #1 bottles are reused, as they commonly are, they can leach chemicals such as DEHA, a possible human carcinogen, and benzyl butyl phthalate (BBP), a potential hormone disruptor. Also, because the plastic is porous you’ll likely get a swill of harmful bacteria with each gulp if you reuse #1 plastic bottles.

Noting that the federal share of funding for water systems has declined from 78 percent in 1973 to 3 percent today, Kaplan urges consumers to “support public policies that promote safe, affordable, public tap water for future generations.” Visit www.foodandwaterwatch.org and take the pledge to take back the tap, promising to choose tap water over bottled whenever possible and to support policies that promote clean public tap water for everybody. And meanwhile, invest in a safe, reusable bottle.

http://www.thegreenguide.com/food/buying/tapped-out/1

For the past 40 years R-22 has been the refrigerant of choice for most residential H.V.A.C. equipment. R-22 is a chlorine based HCFC. An HCFC molecule is made of chlorine, fluorine, carbon and hydrogen atoms. It has been tested and is believed that because of how R-22 is produced, that it plays a part in ozone depletion. The theory is that when the molecules that are contained in R-22 refrigerant are released into the atmosphere they are eventually broken down into their individual atoms and the chlorine atoms then react with the ozone and cause ozone destruction to happen faster than ozone creation. How are you and your family affected by ozone depletion? The stratospheric ozone protects us, our animals and our plans from dangerous ultraviolet rays and as the ozone depletes it loses its ability to protect us from the dangerous ultraviolet rays thus causing increased possibilities of things like skin cancers and cataracts.

The Montreal Protocol is an international treaty designed to protect the ozone layer by phasing out the production of substances that are believed to play a part in ozone depletion. At the first signing of the treaty in 1987 it was decided that R-22 refrigerant would be one of the substances to eventually be phased out of production. Twenty years later R-22 is, in fact, being phased out of production and as of January 1, 2010 all new residential H.V.A.C. equipment manufactured in the United States will no longer use R-22. Understand that this is NEW manufactured equipment. R-22 will still be available to the consumer and equipment that already uses R-22 can still be serviced and if necessary recharged with R-22 up until January 1, 2020. ALL new production of R-22 refrigerant will be stopped as of January 1, 2020.

Replacing the R-22 is the new R-410A refrigerant. Starting January 1, 2010 all H.V.A.C. equipment manufactured in the U.S. will use R-410A. EarthPure        (R-410A) as it is also called is a HFC (non chlorine based) refrigerant with zero ozone depletion potential. Besides being ozone friendly R-410A refrigerant also captures heat and releases it better than R-22, which means that an air conditioer that uses R-410A requires less refrigerant that the same size system that uses R-22. The not so good news is that R-410A can not be used in systems that were built to use R-22 and if your system is older, it most likely uses R-22 refrigerant.

So the question is what to do if you have an R-22 system that has a coil that need to be replaced. Do you replace just the coil and continue using the R-22 or do you think about replacing the entire system? The answer depends on a few things. One thing to consider is how old your system is. If the system is still under warranty then it might be a good idea to go ahead and replace the part, but if the system is out of warranty you will want to consider replacing the entire unit and not just the part. The life span of a system is anywhere for 10-20 years and so if you have an older system you will most likely be better off replacing the system with one that uses the R-410A. Remember the R-22 will only be manufactured in the U.S. for another 10 years and many R-22 manufacturers are aleady closing their doors and so eventually their will be a cap on the amount of R-22 that is available which will create a price increase for all R-22 refrigerant. Every major air conditioner manufacturer in the U.S. has chosen    R-410A  to replace R-22. The choice for the environment and the choice of U.S. air conditioner manufacturers is R-410A refrigerant.

What is thermal bridging and why is it important that we pay close attention to its effects in the homes we build?

The importance lies in the different materials we use to build our wall systems, how much of these materials we use and what conductivity these materials have. We all know that exterior walls have (or should have) insulation, and its purpose is to slow down movement of heat through our walls.

Most of you know about the R-value of insulation materials. R-value rates the materials’ resistance to heat-transfer: the higher the R-value, the lower the heat-transfer. The illustration above best shows how the different materials in the walls affect heat transfer.

We also know that most of our wall assemblies in residential construction are built with wood studs and wood sheathing on the exterior. Soft woods have almost 3 times the conductivity rate of fiberglass insulation, so heat transfers much more quickly through the parts of the wall assembly that are made out of wood, essentially bypassing the insulation. This process is called "thermal bridging" and it results in a lower overall R-value of your wall assembly. Most people mistakenly think that because they insulate their wall with R-19 fiberglass insulation, they have an R-19 wall, when in reality their wall has a much lower effective R-value.

What does that mean from a practical standpoint? Well, let’s put it in the simplest way possible: the more wood studs in your wall assembly, the lower the R-value of your wall.

How can we solve this and make our wall assembly more energy efficient? Obviously, by using less wood in our walls to allow for less thermal bridging and more insulation in the assembly.  But how exactly can we achieve this? There are several ways: we can use systems like SIPs (structural insulated panels), ICFs (insulated concrete forms) or use advanced framing techniques. I will post follow-up articles on all of these solutions in the coming days.

Links to other articles in this series:

Exterior Wall Assemblies… or “How to build a better house” – Part2 of 7

Sources: BuildingGreen.com , BuildingAmerica.gov , eeba.org

IMAGE CREDITS: Illustration by Julia Jandrisits

In residential central heating and cooling systems, the conditioned (heated or cooled) air is delivered to each room of the home through a "supply" duct system, the first half of the duct system. These ducts are used as pathways to deliver air to each room in the home and the "return" duct system or second half of the duct system, returns air to the heating and cooling system. The condition of both duct systems is vital to the overall efficiency of the heating and cooling system and the comfort levels in each room of the entire home. 

Energy loss is not the only concern, duct systems can also affect the indoor air quality of a home. If the return duct system is leaky, it could be drawing stale or polluted air into the duct system and distributing it throughout the home. This air could come from an attic, combustion air from the gas furnace, stove, water heater, or the outside. If the supply duct system is leaky, the home can become depressurized and air from outside may be drawn into the home through infiltration. Either situation may contribute to breathing problems such as allergies and asthma.

Now that you know that duct systems can affect both energy usage and indoor air quality, how do you know if your duct system is in good condition? The most reliable and cost-effective way to determine this is to have a "duct test" using the proper test equipment. Duct testing is the process of using calibrated mechanical equipment to measure the amount of airflow that is lost through the duct system when it is pressurized to its normal operating pressure. While some joints or seams may have only small leaks, other sections may be completely disconnected.

Duct testing can indicate the relative leakiness of the ducts and help determine if the duct system should be sealed, repaired, or renovated. Duct testing is strongly recommended when a new heating and air conditioning unit is being installed. If the existing duct is leaky and inefficient before the new unit is installed, it will still be leaky and inefficient after the new unit is installed unless the ducts are sealed. It does not make sense to install a new energy efficient heating and air conditioning unit unless the duct system is also energy efficient and provides the correct amount of heated or cooled air to each room.

Geothermal technology uses the earth’s renewable energy, located below the earth’s surface to heat and cool your home. A few hundred feet below your home the earth’s temperature remains a constant 45 to 70 degrees Fahrenheit.  Wells are drilled around your home at a depth of 250-300 feet. Pipe is then dropped into the holes which creates a loop.  Fluid is circulated through the pipes. The fluid, which consists of water and non-toxic antifreeze, absorbs the heat from the earth and carries it through the pipe, to a heat pump located in the house. The heat pump circulates the warm air/cool air into the home. In the summer the process is reversed. The heat is transferred from the air in the house by the heat pump. Then heat is the then transferred back to the earth via the water-antifreeze fluid that is running through the pipes.  Geothermal heating and cooling is the most efficient and environmentally responsible way to heat and cool your home!