Category Archives: Uncategorized

Knob-and-Tube Wiring

Knob and Tube Wiring

Knob-and-Tube Wiring

by Nick Gromicko and Kenton Shepard
Knob-and-tube (K&T) wiring was an early standardized method of electrical wiring in buildings, in common use in North America from about 1880 to the 1940s. The system is considered obsolete and can be a safety hazard, although some of the fear associated with it is undeserved.

InterNACHI inspectors should always disclaim knob-and-tube wiring during their inspections.

Facts About Knob-and-Tube Wiring:

  • It is not inherently dangerous. The dangers from this system arise from its age, improper modifications, and situations where building insulation envelops the wires.
  • It has no ground wire and thus cannot service any three-pronged appliances.
  • While it is considered obsolete, there is no code that requires its complete removal.
  • It is treated differently in different jurisdictions. In some areas, it must be removed at all accessible locations, while others merely require that it not be installed in new construction.
  • It is not permitted in any new construction.

How Knob-and-Tube Wiring Works:           

K&T wiring consists of insulated copper conductors passing through lumber framing drill-holes via protective porcelain insulating tubes. They are supported along their length by nailed-down porcelain knobs. Where wires enter a wiring device, such as a lamp or switch, or were pulled into a wall, they are protected by flexible cloth or rubber insulation called “loom.”

Advantages of Knob-and-Tube Wiring:

  • K&T wiring has a higher ampacity than wiring systems of the same gauge. The reason for this is that the hot and neutral wires are separated from one another, usually by 4 to 6 inches, which allows the wires to readily dissipate heat into free air.
  • K&T wires are less likely than Romex cables to be punctured by nails because K&T wires are held away from the framing.
  • The porcelain components have an almost unlimited lifespan.
  • The original installation of knob-and-tube wiring is often superior to that of modern Romex wiring. K&T wiring installation requires more skill to install than Romex and, for this reason, unskilled people rarely ever installed it.

Problems Associated with K&T Wiring:

  • Unsafe modifications are far more common with K&T wiring than they are with Romex and other modern wiring systems. Part of the reason for this is that K&T is so old that more opportunity has existed for improper modifications.
  • The insulation that envelopes the wiring is a fire hazard.
  • It tends to stretch and sag over time.
  • It lacks a grounding conductor. Grounding conductors reduce the chance of electrical fire and damage to sensitive equipment.
  • In older systems, wiring is insulated with varnish and fiber materials that are susceptible to deterioration.

Compared with modern wiring insulation, K&T wiring is less resistant to damage.  K&T wiring insulated with cambric and asbestos is not rated for moisture exposure. Older systems contained insulation with additives that may oxidize copper wire. Bending the wires may cause insulation to crack and peel away.

K&T wiring is often spliced with modern wiring incorrectly by amateurs. This is perhaps due to the ease by which K&T wiring is accessed.

Building Insulation:

K&T wiring is designed to dissipate heat into free air, and insulation will disturb this process. Insulation around K&T wires will cause heat to build up, and this creates a fire hazard. The 2008 National Electrical Code (NEC) requires that this wiring system not be covered by insulation. Specifically, it states that this wiring system should not be in…

hollow spaces of walls, ceilings and attics where such spaces are insulated by loose, rolled or foamed-in-place insulating material that envelops the conductors.

Local jurisdictions may or may not adopt the NEC’s requirement. The California Electrical Code, for instance, allows insulation to be in contact with knob-and-tube wiring, provided that certain conditions are met, such as, but not limited to, the following:

  • A licensed electrical contractor must certify that the system is safe.
  • The certification must be filed with the local building department.
  • Accessible areas where insulation covers the wiring must be posted with a warning sign. In some areas, this sign must be in Spanish and English.
  • The insulation must be non-combustible and non-conductive.
  • Normal requirements for insulation must be met.

Modifications:

When K&T wiring was first introduced, common household electrical appliances were limited to little more than toasters, tea kettles, coffee percolators and
clothes irons. The electrical requirements of mid- to late-20th century homes
could not have been foreseen during the late 18th century, a time during which electricity, to many, was seen as a passing fad. Existing K&T systems are notorious for modifications made in an attempt to match the increasing amperage loads required by televisions, refrigerators, and a plethora of other electric appliances. Many of these attempts were made by insufficiently trained handymen, rather than experienced electricians, whose work made the wiring system vulnerable to overloading.
  • Many homeowners adapted to the inadequate amperage of K&T wiring by installing fuses with resistances that were too high for the wiring. The result of this modification is that the fuses would not blow as often and the wiring would suffer heat damage due to excessive amperage loads.
  • It is not uncommon for inspectors to find connections wrapped with masking tape or Scotch tape instead of electrical tape.

K&T Wiring and Insurance:

Many insurance companies refuse to insure houses that have knob-and-tube wiring due to the risk of fire. Exceptions are sometimes made for houses where an electrical contractor has deemed the system to be safe.

Advice for those with K&T wiring:

  • Have the system evaluated by a qualified electrician. Only an expert can confirm that the system was installed and modified correctly.
  • Do not run an excessive amount of appliances in the home, as this can cause a fire.
  • Where the wiring is brittle or cracked, it should be replaced. Proper maintenance is crucial.
  • K&T wiring should not be used in kitchens, bathrooms, laundry rooms or outdoors. Wiring must be grounded in order to be used safely in these locations.
  • Rewiring a house can take weeks and cost thousands of dollars, but unsafe wiring can cause fires, complicate estate transactions, and make insurers skittish.
  • Homeowners should carefully consider their options before deciding whether to rewire their house.
  • The homeowner or an electrician should carefully remove any insulation that is found surrounding K&T wires.
  • Prospective home buyers should get an estimate of the cost of replacing K&T wiring. They can use this amount to negotiate a cheaper price for the house.

In summary, knob-and-tube wiring is likely to be a safety hazard due to improper modifications and the addition of building insulation. Inspectors need to be wary of this old system and be prepared to inform their clients about its potential dangers.

From Knob-and-Tube Wiring – InterNACHI http://www.nachi.org/knob-and-tube.htm#ixzz2lBpFwyBo

Chinese Drywall

Chinese Drywall

by Nick Gromicko and Kenton Shepard
Amidst a wave of Chinese import scares, ranging from toxic toys to tainted  pet food, reports of contaminated drywall from that country have been popping up  across the American Southeast. Chinese companies use unrefined “fly ash,” a coal  residue found in smokestacks in coal-fired power plants in their manufacturing  process. Fly ash contains strontium sulfide, a toxic substance commonly found in  fireworks. In hot and wet environments, this substance can offgas into hydrogen  sulfide, carbon disulfide, and carbonyl sulfide and contaminate a home’s air  supply. 

The bulk of these incidents have been reported in Florida and other southern  states, likely due to the high levels of heat and humidity in that region. Most  of the affected homes were built during the housing boom between 2004 and 2007,  especially in the wake of Hurricane Katrina when domestic building materials  were in short supply. An estimated 250,000 tons of drywall were imported from  China during that time period because it was cheap and plentiful. This material  was used in the construction of approximately 100,000 homes in the United  States, and many believe this has lead to serious health and property  damage.
Although not believed to be life- threatening, exposure to high  levels of airborne hydrogen sulfide and other sulfur compounds from contaminated  drywall can result in the following physical ailments:

  • sore throat;
  • sinus irritation;
  • coughing;
  • wheezing;
  • headache;
  • dry or burning eyes; and/or
  • respiratory infections.
Due to this problem’s recent nature, there are currently no government or  industry standards for inspecting contaminated drywall in homes. Professionals  who have handled contaminated drywall in the past may know how to inspect for  sulfur compounds but there are no agencies that offer certification in this form  of inspection. Homeowners should beware of con artists attempting to make quick  money off of this widespread scare by claiming to be licensed or certified  drywall inspectors. InterNACHI has assembled the following tips that inspectors  can use to identify if a home’s drywall is contaminated:
  • The house has a strong sulfur smell reminiscent of rotten eggs.
  • Exposed copper wiring appears dark and corroded. Silver jewelry and  silverware can become similarly corroded and discolored after several months of  exposure.
  • A manufacturer’s label on the back of the drywall can be used to link it  with manufacturers that are known to have used contaminated materials. One way  to look for this is to enter the attic and remove some of the insulation.
  • Drywall samples can be sent to a lab to be tested for dangerous levels of  sulfur. This is the best testing method but also the most  expensive.
Contaminated Chinese drywall cannot be repaired. Affected homeowners are  being forced to either suffer bad health and failing appliances due to wire  corrosion or replace the drywall entirely, a procedure which can cost tens of  thousands of dollars. This contamination further reduces home values in a real  estate environment already plagued by crisis. Some insurance companies are  refusing to pay for drywall replacement and many of their clients are facing  financial ruin. Class-action lawsuits have been filed against homebuilders,  suppliers, and importers of contaminated Chinese drywall. Some large  manufacturers named in these lawsuits are Knauf Plasterboard Tianjin, Knauf  Gips, and Taishan Gypsum.
The Florida Department of Health recently tested drywall from three  Chinese manufacturers and a domestic sample and published their findings. They  found “a distinct difference in drywall that was manufactured in the United  States and those that were manufactured in China.” The Chinese samples contained  traces of strontium sulfide and emitted a sulfur odor when exposed to moisture  and intense heat, while the American sample did not. The U.S. Consumer Safety  Commission is currently performing similar tests. Other tests performed by  Lennar, a builder that used Chinese drywall in 80 Florida homes, and Knauf  Plasterboard, a manufacturer of the drywall, came to different  conclusions than the Florida Department of Health. Both found safe levels  of sulfur compounds in the samples that they tested. There is currently no  scientific proof that Chinese drywall is responsible for the allegations against  it.
Regardless of its source, contamination of some sort is damaging property  and health in the southern U.S. The media, who have publicized the issue,  almost unanimously report that the blame lies with imported Chinese  drywall that contains corrosive sulfur compounds originating from ash produced  by Chinese coal-fired power plants. Homes affected by this contamination can  suffer serious damage to the metal parts of appliances and piping and lead,  potentially leading to considerable health issues. While no governing body  has issued regulations regarding contaminated drywall, it is advisable that home  inspectors be aware of the danger it poses and learn how to identify it.

From  Chinese Drywall – Int’l Association of Certified Home Inspectors (InterNACHI) http://www.nachi.org/chinese-drywall.htm#ixzz2eVWCDr00

Anti-Tip Brackets for Freestanding Ranges

Anti-Tip DeviceAnti-Tip Brackets for Freestanding Ranges

by Nick Gromicko and Kenton Shepard

Anti-tip brackets are metal devices designed to prevent freestanding ranges from tipping. They are normally attached to a rear leg of the range or screwed into the wall behind the range, and are included in all installation kits. A unit that is not equipped with these devices may tip over if enough weight is applied to its open door, such as that from a large Thanksgiving turkey, or even a small child. A falling range can crush, scald, or burn anyone caught beneath.

 
Bracket Inspection

Inspectors can confirm the presence of anti-tip brackets through the following methods:

  • It may be possible to see a wall-mounted bracket by looking over the rear of the range. Floor-mounted brackets are often hidden, although in some models with removable drawers, such as 30-inch electric ranges made by General Electric, the drawers can be removed and a flashlight can be used to search for the bracket. Inspectors should beware that a visual confirmation does not guarantee that the bracket has been properly installed.
  • Inspectors can firmly grip the upper-rear section of the range and tip the unit. If equipped with an anti-tip bracket, the unit will not tip more than several inches before coming to a halt. The range should be turned off, and all items should be removed from the stovetop before this action can be performed. It is usually easier to detect a bracket by tipping the range than through a visual search. This test can be performed on all models and it can confirm the functionality of a bracket.
If no anti-tip bracket is detected, inspectors should recommend that one be installed.
Clients can contact the dealer or builder who installed their range and request that they install a bracket. For clients who wish to install a bracket themselves, the part can be purchased at most hardware stores or ordered from a manufacturer. General Electric will send their customers an anti-tip bracket for free.
According to the U.S. Consumer Product Safety Commission (CPSC), there were 143 incidents caused by range tip-overs from 1980 to 2006. Of the 33 incidents that resulted in death, most of those victims were children. A small child may stand on an open range door in order to see what is cooking on the stovetop and accidentally cause the entire unit to fall on top of him, along with whatever hot items may have been cooking on the stovetop. The elderly, too, may be injured while using the range for support while cleaning. InterNACHI inspectors who inspect ovens should never leave the oven door open while he oven is unattended.
In response to this danger, the American National Standards Institute (ANSI) and Underwriters Laboratories (UL) created standards in 1991 that require all ranges manufactured after that year to be capable of remaining stable while supporting 250 pounds of weight on their open doors. Manufacturers’ instructions, too, require that anti-tip brackets provided be installed. Despite these warnings, retailer Sears estimated in 1999 that a mere 5% of the gas and electric units they sold were ever equipped with anti-tip brackets. As a result of Sears’ failure to comply with safety regulations, they were sued and subsequently required to secure ranges in nearly 4 million homes, a measure that has been speculated to have cost Sears as much as $500 million.
In summary, ranges are susceptible to tipping if they are not equipped with anti-tip brackets. Inspectors should know how to confirm that these safety devices are present.

From Anti-Tip Brackets for Freestanding Ranges – InterNACHI http://www.nachi.org/anti-tip.htm#ixzz2eV6cLDaN

10 Easy Ways to Save Energy in Your Home

10 Easy Ways to Save Energy in Your Home

by Nick Gromicko, Ben Gromicko, and Kenton Shepard 

Most people don’t know how easy it is to make their homes run on less energy, and here at InterNACHI, we want to change that. Drastic reductions in heating, cooling and electricity costs can be accomplished through very simple changes, most of which homeowners can do themselves. Of course, for homeowners who want to take advantage of the most up-to-date knowledge and systems in home energy efficiency, InterNACHI energy auditors can perform in-depth testing to find the best energy solutions for your particular home.

Why make your home more energy efficient? Here are a few good reasons:

  • Federal, state, utility and local jurisdictions’ financial incentives, such as tax breaks, are very advantageous for homeowners in most parts of the U.S.
  • It saves money. It costs less to power a home that has been converted to be more energy-efficient.
  • It increases the comfort level indoors.
  • It reduces our impact on climate change. Many scientists now believe that excessive energy consumption contributes significantly to global warming.
  • It reduces pollution. Conventional power production introduces pollutants that find their way into the air, soil and water supplies.

1. Find better ways to heat and cool your house. 

As much as half of the energy used in homes goes toward heating and cooling. The following are a few ways that energy bills can be reduced through adjustments to the heating and cooling systems:

  • Install a ceiling fan. Ceiling fans can be used in place of air conditioners, which require a large amount of energy.
  • Periodically replace air filters in air conditioners and heaters.
  • Set thermostats to an appropriate temperature. Specifically, they should be turned down at night and when no one is home. In most homes, about 2% of the heating bill will be saved for each degree that the thermostat is lowered for at least eight hours each day. Turning down the thermostat from 75° F to 70° F, for example, saves about 10% on heating costs.
  • Install a programmable thermostat. A programmable thermostat saves money by allowing heating and cooling appliances to be automatically turned down during times that no one is home and at night. Programmable thermostats contain no mercury and, in some climate zones, can save up to $150 per year in energy costs.
  • Install a wood stove or a pellet stove. These are more efficient sources of heat than furnaces.
  • At night, curtains drawn over windows will better insulate the room.

2. Install a tankless water heater.

Demand-type water heaters (tankless or instantaneous) provide hot water only as it is needed. They don’t produce the standby energy losses associated with traditional storage water heaters, which will save on energy costs. Tankless water heaters heat water directly without the use of a storage tank. When a hot water tap is turned on, cold water travels through a pipe into the unit. A gas burner or an electric element heats the water. As a result, demand water heaters deliver a constant supply of hot water. You don’t need to wait for a storage tank to fill up with enough hot water.

3. Replace incandescent lights.

The average household dedicates 11% of its energy budget to lighting. Traditional incandescent lights convert approximately only 10% of the energy they consume into light, while the rest becomes heat. The use of new lighting technologies, such as light-emitting diodes (LEDs) and compact fluorescent lamps (CFLs), can reduce the energy use required by lighting by 50% to 75%. Advances in lighting controls offer further energy savings by reducing the amount of time that lights are on but not being used. Here are some facts about CFLs and LEDs:

  • CFLs use 75% less energy and last about 10 times longer than traditional incandescent bulbs.
  • LEDs last even longer than CFLs and consume less energy.
  • LEDs have no moving parts and, unlike CFLs, they contain no mercury.

4. Seal and insulate your home.

Sealing and insulating your home is one of the most cost-effective ways to make a home more comfortable and energy-efficient, and you can do it yourself. A tightly sealed home can improve comfort and indoor air quality while reducing utility bills. An InterNACHI energy auditor can assess  leakage in the building envelope and recommend fixes that will dramatically increase comfort and energy savings.

The following are some common places where leakage may occur:

  • electrical receptacles/outlets;
  • mail slots;
  • around pipes and wires;
  • wall- or window-mounted air conditioners;
  • attic hatches;
  • fireplace dampers;
  • inadequate weatherstripping around doors;
  • baseboards;
  • window frames; and
  • switch plates.

Because hot air rises, air leaks are most likely to occur in the attic. Homeowners can perform a variety of repairs and maintenance to their attics that save them money on cooling and heating, such as:

  • Plug the large holes. Locations in the attic where leakage is most likely to be the greatest are where walls meet the attic floor, behind and under attic knee walls, and in dropped-ceiling areas.
  • Seal the small holes. You can easily do this by looking for areas where the insulation is darkened. Darkened insulation is a result of dusty interior air being filtered by insulation before leaking through small holes in the building envelope. In cold weather, you may see frosty areas in the insulation caused by warm, moist air condensing and then freezing as it hits the cold attic air. In warmer weather, you’ll find water staining in these same areas. Use expanding foam or caulk to seal the openings around plumbing vent pipes and electrical wires. Cover the areas with insulation after the caulk is dry.
  • Seal up the attic access panel with weatherstripping. You can cut a piece of fiberglass or rigid foamboard insulation in the same size as the attic hatch and glue it to the back of the attic access panel. If you have pull-down attic stairs or an attic door, these should be sealed in a similar manner.

5. Install efficient showerheads and toilets.

The following systems can be installed to conserve water usage in homes:

  • low-flow showerheads. They are available in different flow rates, and some have a pause button which shuts off the water while the bather lathers up;
  • low-flow toilets. Toilets consume 30% to 40% of the total water used in homes, making them the biggest water users. Replacing an older 3.5-gallon toilet with a modern, low-flow 1.6-gallon toilet can reduce usage an average of 2 gallons-per-flush (GPF), saving 12,000 gallons of water per year. Low-flow toilets usually have “1.6 GPF” marked on the bowl behind the seat or inside the tank;
  • vacuum-assist toilets. This type of toilet has a vacuum chamber that uses a siphon action to suck air from the trap beneath the bowl, allowing it to quickly fill with water to clear waste. Vacuum-assist toilets are relatively quiet; and
  • dual-flush toilets. Dual-flush toilets have been used in Europe and Australia for years and are now gaining in popularity in the U.S. Dual-flush toilets let you choose between a 1-gallon (or less) flush for liquid waste, and a 1.6-gallon flush for solid waste. Dual-flush 1.6-GPF toilets reduce water consumption by an additional 30%.

6. Use appliances and electronics responsibly.

Appliances and electronics account for about 20% of household energy bills in a typical U.S. home. The following are tips that will reduce the required energy of electronics and appliances:

  • Refrigerators and freezers should not be located near the stove, dishwasher or heat vents, or exposed to direct sunlight. Exposure to warm areas will force them to use more energy to remain cool.
  • Computers should be shut off when not in use. If unattended computers must be left on, their monitors should be shut off. According to some studies, computers account for approximately 3% of all energy consumption in the United States.
  • Use efficient ENERGY STAR-rated appliances and electronics. These devices, approved by the U.S. Department of Energy and the Environmental Protection Agency’s ENERGY STAR Program, include TVs, home theater systems, DVD players, CD players, receivers, speakers, and more. According to the EPA, if just 10% of homes used energy-efficient appliances, it would reduce carbon emissions by the equivalent of 1.7 million acres of trees.
  • Chargers, such as those used for laptops and cell phones, consume energy when they are plugged in. When they are not connected to electronics, chargers should be unplugged.
  • Laptop computers consume considerably less electricity than desktop computers.

7. Install daylighting as an alternative to electrical lighting.

Daylighting is the practice of using natural light to illuminate the home’s interior. It can be achieved using the following approaches:

  • skylights. It’s important that they be double-pane or they may not be cost-effective. Flashing skylights correctly is key to avoiding leaks;
  • light shelves. Light shelves are passive devices designed to bounce light deep into a building. They may be interior or exterior. Light shelves can introduce light into a space up to 2½ times the distance from the floor to the top of the window, and advanced light shelves may introduce four times that amount;
  • clerestory windows.  Clerestory windows are short, wide windows set high on the wall. Protected from the summer sun by the roof overhang, they allow winter sun to shine through for natural lighting and warmth; and
  • light tubes.  Light tubes use a special lens designed to amplify low-level light and reduce light intensity from the midday sun. Sunlight is channeled through a tube coated with a highly reflective material, and then enters the living space through a diffuser designed to distribute light evenly.

8. Insulate windows and doors.

About one-third of the home’s total heat loss usually occurs through windows and doors. The following are ways to reduce energy lost through windows and doors:

  • Seal all window edges and cracks with rope caulk. This is the cheapest and simplest option.
  • Windows can be weatherstripped with a special lining that is inserted between the window and the frame. For doors, apply weatherstripping around the whole perimeter to ensure a tight seal when they’re closed. Install quality door sweeps on the bottom of the doors, if they aren’t already in place.
  • Install storm windows at windows with only single panes. A removable glass frame can be installed over an existing window.
  • If existing windows have rotted or damaged wood, cracked glass, missing putty, poorly fitting sashes, or locks that don’t work, they should be repaired or replaced.

9. Cook smart.

An enormous amount of energy is wasted while cooking. The following recommendations and statistics illustrate less wasteful ways of cooking:

  • Convection ovens are more efficient that conventional ovens. They use fans to force hot air to circulate more evenly, thereby allowing food to be cooked at a lower temperature. Convection ovens use approximately 20% less electricity than conventional ovens.
  • Microwave ovens consume approximately 80% less energy than conventional ovens.
  • Pans should be placed on the matching size heating element or flame.
  • Using lids on pots and pans will heat food more quickly than cooking in uncovered pots and pans.
  • Pressure cookers reduce cooking time dramatically.
  • When using conventional ovens, food should be placed on the top rack. The top rack is hotter and will cook food faster.

10. Change the way you do laundry.

  • Do not use the medium setting on your washer. Wait until you have a full load of clothes, as the medium setting saves less than half of the water and energy used for a full load.
  • Avoid using high-temperature settings when clothes are not very soiled. Water that is 140° F uses far more energy than 103° F for the warm-water setting, but 140° F isn’t that much more effective for getting clothes clean.
  • Clean the lint trap every time before you use the dryer. Not only is excess lint a fire hazard, but it will prolong the amount of time required for your clothes to dry.
  • If possible, air-dry your clothes on lines and racks.
  • Spin-dry or wring clothes out before putting them into a dryer.
Homeowners who take the initiative to make these changes usually discover that the energy savings are more than worth the effort. InterNACHI home inspectors can make this process much easier because they can perform a more comprehensive assessment of energy-savings potential than the average homeowner can.

From 10 Easy Ways to Save Energy in Your Home – InterNACHI http://www.nachi.org/increasing-home-energy-efficiency-client.htm#ixzz2d16392rU