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Monday, November 15, 2010

Attics Without Ventilation becoming more popular

Unvented Roof Assemblies

by Nick Gromicko and Rob London
Unvented roof assemblies are becoming an increasingly common construction alternative to traditional vented roofs. They are designed without ventilation openings, and the attic is conditioned like the rest of the living space.
 Un-vented roofs offer certain advantages if they are designed properly
Unvented roofs operate by the principle that venting is not necessary to control moisture accumulation. The following conditions must be met in order for an unvented roofing assembly to function properly:
    • The building envelope must be tight, including having adequate vapor and air barriers installed, which is generally accomplished through the use of spray-foam insulation.
    • The building must be pressurized in order to counter the stack effect, which happens when hot, pressurized air in the upper part of the house tries to escape through holes in the building envelope. 
Proponents argue that, when installed and implemented properly, unvented roofing assemblies offer the following advantages over vented attics:
  • enhanced comfort. Wind, temperature gradients and pressure differences in a vented attic create undesirable air movement between the living space and the attic. Also, unvented attics block volatile organic compounds and other moisture-related airborne particles from migrating to the living space from the attic;
  • protection against certain moisture-related problems. In vented attics in cold climates, warm air can leak from the living space and condense on the underside of the roof sheathing, while humid air can easily leak from the outdoors and condense on cold metal surfaces of ductwork and air-conditioning equipment typically located in the attic. Unvented attics do not experience such problems;Ice dams may form on un-vented roofs
  • energy conservation. An unvented attic is conditioned space and won’t be subject to the extremes of temperature common to vented attics. Heat is thus less likely to escape into an unvented attic from HVAC equipment, and if it does, it will remain within the conditioned space. Insulation around ducts and HVAC equipment becomes less critical, and the equipment is not forced to work as hard to compensate for unwanted air or heat loss. It might be possible to downsize the HVAC system if enough energy is saved in this manner. Also, cold air blowing through the eave vents in a vented attic can degrade the thermal performance of attic insulation; 
  • snow and ember barrier. Openings in the soffits, gables, mushroom and ridge vents easily allow snow intrusion, especially fine snowflakes, into the attic. The snow can accumulate and eventually melt, causing damage to building materials and encouraging the growth of mold. Airborne mold spores may pass through vented attics into the living space and harm susceptible individuals. Also, blowing embers from wildfires can pass through unscreened attic vents and light the house on fire. These blowing embers often fall far from the edge of the actual wildfire, which might not otherwise have reached the house; and
  • expanded use and design options. Because the temperature in unvented attics is more easily controlled, they can be furnished and incorporated into the living space or used as a conditioned storage space. Also, unvented roof assembles make complicated roof geometries more viable, as they are difficult to ventilate effectively.
While unvented attics are gaining acceptance, homeowners must realize their limitations, including:
  • codes. Many local building codes do not account for non-standard construction alternatives such as unvented attic assemblies. They were addressed in the 2006 International Residential Code (IRC), however, which states that they must have no vapor retarder installed between the attic and the home's living space, and there must be air-impermeable insulation installed between the rafters;
  • asphalt shingles may fail prematurely due to increased exposure to heat; and 
  • ice dams are more likely to form at unvented attics in cold climates.
Inspectors and homeowners should understand that unvented roof assemblies are a controversial idea. The Asphalt Roofing Manufacturers Association (ARMA), for instance, has argued that the IRC's acceptance in 2006 of this design should be repealed.  ARMA representative Dave Roodvoets
has stated,  “Even the best researchers have only a few years of data on unvented attics in humid climates."  ARMA also contends that unvented roofs may make a building more susceptible to decay by trapping moisture inside. Proponents of the design have countered this contention by pointing out that in humid climates, most moisture comes from the exterior.

In summary, unvented roofs offer certain advantages if they are designed properly. 
"When Experience Matters"


Bed Bugs

Bed Bugs: Inspecting for the New "House Herpes"

by Nick Gromicko and Rob London
Bed bugs are small, flightless, rust-colored parasites that feed on the blood of humans and other warm-blooded animals. Inspectors should learn the telltale signs of these pests and be capable of providing information to their clients. Adult bed bug
Bed bugs were diminished to an historical footnote after their near-eradication in the 1950s, but they are re-emerging in a big way. At the EPA’s National Bed Bug Summit in 2009, researchers decided that the parasite’s revival is more appropriately termed a pandemic rather than an epidemic, noting its rapid spread across large regions and different continents. For those afflicted by the bug, humiliated and defeated by its persistence, many prefer to refer to the infestation as “house herpes.” The United States has seen a 50-fold increase in bed bug infestations over the last five years, according to the National Pest Management Association. An entomologist told MSNBC, “It’s like the return of the wooly mammoth,” as many of his peers had previously never seen a single bed bug in their careers. The outbreak has affected most parts of North America and Europe, especially in urban areas. 
Researchers believe bed bugs have roused from a half-century of hibernation for two reasons:  the termination of the use of the pesticide DDT; and a rise in international travel. DDT, a powerful synthetic pesticide, was used widely in agriculture until a public outcry concerning its safety lead to a US-ban of the chemical in 1972, followed by international bans. Unbeknownst to the environmentalists of the time, these laws would permit future outbreaks to grow unchecked, which is precisely what happened when travel increased from countries where bed bugs were never subjugated, such as India.
Hotbeds of international travel, such as New York City, have hosted the bulk of the carnage. The bugs hitch rides from country to country in suitcases, and creep into hotel rooms where other guests are then exposed and unknowingly spread the parasites to movie theatres, cabs, buses, hospitals, houses, and everywhere in between. In New York City, bed bug reports increased 800% from 2008 to 2009, a year in which the Department of Housing Preservation and Development received 13,152 bug infestation complaints. Bed bug bites
The unpleasantness of a typical rodent or insect extermination is largely the fee charged by the exterminator.  But with bed bugs, this fee is just one piece of a greater nightmare. Because bed bugs are adept at hiding almost anywhere, an alarming quantity of possessions, from curtains to books and picture frames, must be discarded or quarantined. In one posh New York City rental tower, a tenant was forced to part with carpets, bedding, curtains, 20 cashmere sweaters, an Armani suit, a couch, a headboard, a night table, a bedframe, and an exercise bike, according to the New York Daily News. Other victims have had to throw away their books unless they were willing to inspect each one, page by page. Some possessions may be salvaged if they are sealed in special casing long enough for the bed bugs to die, which can takes many months. During this time, residents may be forced to move to temporary housing elsewhere.
Fortunately, the health dangers posed by bed bugs seem to be limited to temporary skin irritation and inflammation, akin to mosquito bites. There are no known cases of disease transmission from bed bugs to humans, despite the fact that the parasites seem similar to other parasites that do transmit disease, such as fleas and ticks. Anaphylactic shock, however, may be experienced by a small percentage of the population, and measures should be taken to prevent bacterial infection of bitten areas.
Adult bed bugs are flat, apple-seed sized with rusty-colored, oval bodies. Newly hatched bed bugs are semi-transparent, light tan in color, and the size of a poppy seed. Yet, due to their elusive nature, their presence is usually discovered through peripheral clues rather than by seeing the bugs themselves. Some of these signs include fecal spots, blood smears, crushed bugs, or the itchy bumps that may result from bites. Bugs may be disturbed while feeding and leave a cluster of bumps, or they may bite in a row, marking the path of a blood vessel. The parasites emit a characteristic musty odor, although the smell is sometimes not present in even severe infestations. The bugs also emit a smell that is detectable by dogs, which has lead to the implementation of dogs in bed bug detection. Properly trained dogs can find bed bugs in wall voids, furniture gaps, and other places that humans may overlook and, in doing so, they focus on the area in which exterminators must spray. Bed bugs, their eggs and excrement
It is best for bed bugs to be treated by pest management professionals (PMPs), not homeowners, as there is risk that an inexperienced person may spread the infestation further throughout the home. For instance, bug bombs will be ineffective and merely spread bed bugs. Even chemical sprays designed to kill bed bugs, if used by inexperienced homeowners, may make the infestation worse. PMPs can inspect for bed bugs in their immature stages of development, including their eggs, while homeowners cannot. In addition, prep work performed by a homeowner may make it difficult for the PMP to assess the extent of the infestation.
The following tactics may be useful, however, for temporary relief or confirmation of the presence of bed bugs:
  • Remove bed skirts, as they provide easy access for the bugs to travel from the floor to your bed. If you must have bed skirts, make sure they do not reach the floor.
  • Move your bed away from the wall. Bed bugs cannot fly, but they can climb walls in order to fall onto the bed.
  • Place furniture legs in tin cans coated with talcum powder, petroleum jelly or a non-evaporative liquid, to deter the bugs from climbing.
  • Place a strip of duct tape at the base of furniture with the sticky side out. This tactic can be used to confirm the presence of bed bugs because it will trap them in place.
  • Spray cracks and crevices with an insecticide designed to control bed bugs. Follow the label's directions carefully. However, do not treat bedding, towels or clothing with insecticide.
Homeowners can limit their chances of bed bug exposure by purchasing only new furniture, as stowaway bugs can hide in older or used chairs and mattresses. Hostels, hotels and motels host many travelers and are obvious breeding grounds for bed bugs, and many hostels ban sleeping bags for this reason. Unfortunately, person-to-person contact is difficult to avoid.

"When Experience Matters"

Monday, November 8, 2010

50 Ways To Green The Planet

JW Home Inspections, Inc. presents
50 Ways to Green the Planet

If you can't afford a new home or a large remodeling
project, there are still plenty of things you can do to be
environmentally friendly and save money.

1. Update your lighting
Make it a policy to buy energy efficient compact
fluorescent light bulbs. You can now get a variety of
shapes and perfectly match the color hue and lighting for
each room. They look good and use at least two-thirds
less power than regular lighting.

2. Buy Energy Star
When you are ready to buy new home appliances, buy
smart. Check for the Energy Star rating. These more
efficient machines can reduce your utility bill as much as
30-percent. Deb Snoonian, Managing Editor of Plenty
Magazine said, "Energy Start is a program sponsored by
the EPA and the Department of Energy. Essentially, it's a
way for them to recognize the companies and the products
that are most energy-efficient. On average, an Energy
Start appliance -- whether it's a computer monitor, a
refrigerator, a washer or dryer -- is going to be about
30-percent more energy efficient."

3. Wall Warts
Those clunky power adaptors draw energy from the wall all
the time. Unplug them individually or attach them to a
power strip and turn off the whole switch when not in use.
Around 75-percent of all electricity in a home comes from
appliances that are turned off, but are still plugged in.
Make sure that you only have those appliances plugged in
where you're actually using the electricity. You will save on
bills and we as a society will save on energy.

4. Dormant Appliances
Practically every appliance uses electricity even when it's
switched off. Unless it needs power to retain programming
memory, hit the switch. Better yet, make it a family practice.
Amy Schachter, an Upper East Side resident, said, "My
family reminds each other constantly. That's partly money,
partly the fact that we know now that we're creating energy
usage that is totally unnecessary."

5. Energy Audit
You can find out how much energy your home uses each
year with an energy audit. Many utility providers and state
energy departments will audit your home free or at low cost
to help you find ways to be more energy efficient.

Read All 50


Night Light Safety


by Nick Gromicko and Rob London
A nightlight is a small, low-powered electrical light source placed for comfort or convenience in indoor areas that become dark at night.
Facts and Figures
  • Before they were powered electrically, nightlights were usually long-burning candles placed in fireproof metal cups, known as tealights in some countries. (Tealights in the U.S. refer to very short and wide candles that can be purchased within or without an aluminum tin cup that are commonly used inside a decorative glass holder.  They are also known as votive candles.)
  • There are roughly 90 million nightlights purchased each year in the United States. In 2001 alone, more than 600,000 of them were recalled by manufacturers for safety reasons.
  • Defective nightlights can cause fires, burns and electrocutions.
UsesOne of 3,000 Energizer nightlights recalled due to to fire hazards
Nightlights are typically installed to create a sense of security and to alleviate fears of the dark, especially for children. They also illuminate the general layout of a room without causing the eyestrain created by a standard light, helping to prevent tripping down stairs or over objects. This is an important safety measure for older adults, for whom falls are the leading cause of injury-related deaths, according to the National Association for Home Care and Hospice. Nightlights may also be used to mark an emergency exit.
A wide variety of nightlights is available to homeowners; bulbs vary from incandescent to energy-efficient options, such as light-emitting diodes (LEDs), neon lamps, and electroluminescent bulbs. Some of these devices are equipped with a light-sensitive switch that activates the light only when it’s dark enough for them to be required, saving electricity and the effort needed to manually turn them on and off. Some designs also incorporate a rechargeable battery so they will continue to function during power outages.
Nightlights present the following hazards:
  • fire. Nightlights can become excessively hot, causing them to melt and pose a risk of fire if they come in contact with flammable materials, according to the U.S. Consumer Product Safety Commission (CPSC). The CPSC receives roughly 10 reports annually of fires that were caused when nightlights ignited toilet paper, pillows, bedspreads and other flammable materials. In many of these cases, the nightlight was installed so close to the bed that falling blankets or pillows made contact with the nightlight and started a fire. For this reason, nightlights should not be plugged in next to bed coverings, curtains, and other potentially flammable objects and materials. InterNACHI inspectors can also make sure nightlights are not covered with tape, cardboard or any other material that might cause them to overheat. Homeowners may consider using nightlights equipped with mini neon bulbs instead of higher-wattage bulbs;
  • poisoning. So-called “bubble" nightlights are special, decorative nightlights that contain a dangerous chemical called methylene chlDecorative nightlights like this one might attract unsafe attention from small childrenoride. If the vial breaks, the unit should be thrown away immediately and precautions should be taken to avoid skin contact with the leaking chemical; and
  • electric shock. Nightlights pose the risk of electric shock when used outdoors or in locations that may become wet, such near sinks or hot tubs, or in garages or covered patios. They should never be plugged into an extension cord, surge-protector strip, multiple-outlet strip, or other movable types of receptacles. Electric shock is also possible if the nightlight overheats and melts.
The following are a few of the many nightlight models that have been recalled due to electrical and fire hazards:
  • Molenaar™ brand, model numbers 2017 and 2019 that are shaped like a rectangle and a house, respectively, and include the etched engraving "71980 U.S.A": 315,000 units recalled; 
  • Forever-Glo™: 35,000 units recalled;
  • LED Rocketship PalPODzzz™ Portable Nightlights:  26,000 units recalled; and 
  • Energizer™ Light-on-Demand Wallplate Nightlights: 3,000 units recalled.
Additional Tips
  • Plug the nightlight into an exposed wall outlet where it will be well-ventilated.
  • Do not repair any nightlight yourself.  Only replace the bulb.
  • Avoid installing nightlights in locations where they might be exposed to excessive sunlight, as UV rays will degrade the plastic.
  • Never let children handle nightlights. If you have small children, avoid purchasing or installing a nightlight decorated with cute or funny figures to which they may be attracted and that may be easy for them to reach.
In summary, nightlights are used for comfort and safety, although homeowners should take precautions when purchasing and using these devices.

Saturday, November 6, 2010

Ten things you should know about Mold

Ten Things You Should Know About Mold

 1.  Potential health effects and symptoms associated with mold exposure include allergic reactions, asthma, and other respiratory complaints. 
 2.  There is no practical way to eliminate all mold and mold spores in the indoor environment; the way to control indoor mold growth is to control moisture.
 3.  If mold is a problem in your home, you must clean up the mold and eliminate sources of moisture.
 4.  Fix the source of the water problem or leak to prevent mold growth.

 5.  Reduce indoor humidity (to 30% to 60%) to decrease mold growth by: 
        a. venting bathrooms, dryers, and other moisture-generating sources to the outside;
        b. using air conditioners and dehumidifiers;
        c. increasing ventilation; and
       d. using exhaust fans whenever cooking, dish-washing, and cleaning.  
 6.  Clean and dry any damp or wet building materials and furnishings within 24 to 48 hours to prevent mold growth.

 7.  Clean mold off hard surfaces with water and detergent, and dry completely. Absorbent materials that are moldy (such as carpeting and ceiling tiles) may need to be replaced. 

 8.  Prevent condensation.  Reduce the potential for condensation on cold surfaces (i.e., windows, piping, exterior walls, roof and floors) by adding insulation. 

 9.  In areas where there is a perpetual moisture problem, do not install carpeting.

10.  Molds can be found almost anywhere; they can grow on virtually any substance, provided moisture is present. There are molds that can grow on wood, paper, carpet, and foods.

Hot Water Heater: Save Money and Be Safe

Water heaters use a lot of energy and should have the thermostats set to 120 degrees. Not only will this save energy, but dramatically reduces the risk of scalding injuries. What many home owners fail to realize, is if it is set higher, you will be using a lot of cold water to bring the temperature down. Gas hot water heaters have their thermostat on the exterior and are easy to set, electric heaters are under cover and should be set by a professional.

Toxic Drywall from China

It appears there is no shortage of defective products arriving on our shores from China. Recently, attorneys at Morgan & Morgan filed a class action complaint against the manufacturers / distributors of defective Chinese drywall that has allegedly caused electrical damages and health problems for Florida residents.
Shortages in American made drywall products (between 2004 and 2006) prompted some Florida building companies to import drywall from China. It is thought that the drywall was used in new home construction.
As much as 10 million square feet of this defective drywall may have been used in Florida new homes. The defective drywall supposedly emits sulfur compounds, leading to electrical damages and health problems (including respiratory problems, nose bleeds, headaches, and irritated eyes).  The drywall emits a strong sulfur (rotten egg) odor.
More information on the Class Action Lawsuit
Thanks, and be careful what you hang on your walls.  Be safe.
John M. Wickline
JW Home Inspections, Inc.
John is the president of JW Home Inspections, Inc., serving the Low Country of South Carolina, Hilton Head, Bluffton, Sun City, Beaufort, Hardeeville, Ridgeland, Callawassie, and Daufuskie Island since 1998. He is licensed in South Carolina and a certified member of InterNACHI.