Home Inspection FYI

Providing Help, Knowledge and Other Useful Information To Home Owners Everywhere

Home Inspection FYI - Providing Help, Knowledge and Other Useful Information To Home Owners Everywhere

Exhaust Fans and Bathroom Ventilation

Ventilation systems for bathrooms are designed to exhaust odors and moist air to the home’s exterior from the bathroom. Typical ventilation systems consist of a ceiling fan unit in the ceiling of the bathroom connected to a duct that terminates at the roof.

Exhaust Fan Ventilation Functions;

The exhaust fan may be controlled in one of several ways:

  • Most are controlled by a conventional wall switch.
  • A timer switch may be mounted on the wall.
  • A wall-mounted humidistat can be pre-set to turn the fan on and off based on different levels of relative humidity
    Bathroom ventilation fan Exhaust Fans and Bathroom Ventilation.

Newer exhaust fans may be very quiet but work just fine. Older exhaust fans may be very noisy or very quiet. If an older exhaust fan is quiet, it may not be working well. Inspectors can test for adequate exhaust fan airflow with a chemical smoke pencil or a powder puff bottle.
Bathroom ventilation fans should be inspected for dust buildup that can impede airflow. Particles of moisture-laden animal dander and lint are attracted to the fan because of its static charge. Inspectors should comment on dirty fan covers.

Ventilation systems should be installed in all bathrooms. This includes any bathroom with windows, since windows will not be opened during the winter in cold climates.

Defects in Poor Ventilation

The following conditions indicate insufficient bathroom ventilation:

  • moisture stains on walls or ceilings.
  • corrosion of metal.
  • visible mold on walls or ceilings.
  • peeling paint or wallpaper.
  • frost on windows.
  • high levels of humidity.

The most common defect related to bathroom ventilation systems is improper termination of the duct. Ventilation ducts must terminate at the home exterior. The most common improper ventilation duct terminations locations are:

  • mid-level in the attic. These are easy to spot.
  • beneath the insulation. You need to remember to look. The duct may terminate beneath the insulation or there may be no duct installed.
  • beneath attic vents. The duct must terminate at the home exterior, not just beneath it.

Improperly terminated ventilation systems may appear to work fine from inside the bathroom; you have to look in the attic or on the roof. Sometimes poorly-installed ventilation ducts will loosen or become disconnected at joints or connections.

Ventilation ducts which leak or terminate in attics can cause problems from condensation. Warm, moist air will condense on cold attic framing, insulation or other materials. This condition has the potential to cause health or decay problems from mold, or to damage materials such as drywall. Moisture also reduces the effectiveness of thermal insulation.

Mold and Poor Ventilation

Perhaps the most serious consequence of an improper ventilation setup is the potential accumulation of mold in attics or crawlspaces. Mold may appear as a fuzzy, thread-like, cobwebby fungus, although it can never be identified with certainty without being lab-tested. Health problems caused by mold are related to high concentrations of spores in indoor air. “Spores” are like microscopic seeds, released by mold fungi when they reproduce. Every home has mold. Moisture levels of about 20% in materials will cause mold colonies to grow. Inhaling mold spores can cause health problems in those with asthma or allergies, and can cause serious or fatal fungal infections in those with lung disease or compromised immune systems.

Mold is impossible to identify visually and must be tested by a lab in order to be confidently labeled. Inspectors should refrain from calling anything “mold” but should refer to anything that appears as mold as a material that “appears to be microbial growth.” Inspectors should include in their report, and in the inspection agreement signed by the client, a disclaimer clearly stating that the General Home Inspection is an inspection for safety and system defects, not a mold inspection.

Decay, which is rot, is also caused by fungi. Incipient (early) decay cannot be seen. By the time decay becomes visible, wood may have lost up to 50% of its strength.

In order to grow, mold fungi require that the following conditions are present:

  • oxygen;
  • temperatures between approximately 45° F and 85° F;
  • food. This includes a wider variety of materials found in homes; and
  • moisture.

If insufficient levels of any of these requirements exist, all mold growth will stop and fungi will go dormant. Most are difficult to actually kill.

Even though mold growth may take place in the attic, mold spores can be sucked into the living areas of a residence by low air pressure. Low air pressure is usually created by the expulsion of household air from exhaust fans in bathrooms, dryers, kitchens and heating equipment.

Improper Ventilationbath fan attic termination Exhaust Fans and Bathroom Ventilation

Ventilation ducts must be made from appropriate materials and oriented effectively in order to ensure that stale air is properly exhausted.

Ventilation ducts must:

  • terminate outdoors. Ducts should never terminate within the building envelope.
  • contain a screen or louvered (angled) slats at its termination to prevent bird, rodent and insect entry.
  • be as short and straight as possible and avoid turns. Longer ducts allow more time for vapor to condense and also force the exhaust fan to work harder.
  • be insulated, especially in cooler climates. Cold ducts will encourage condensation.
  • protrude at least several inches from the roof.
  • be equipped with a roof termination cap that protects the duct from the elements.
  • be installed to manufacturer’s recommendations.

The following tips are helpful although not required. Ventilation ducts should:

  • be made from inflexible metal, PVC, or other rigid material. Unlike dryer exhaust vents, they should not droop.
  • have smooth interiors. Ridges will encourage vapor to condense, allowing water to back-flow into the exhaust fan or leak through joints onto vulnerable surfaces.

Above all else, a bathroom ventilation fan should be connected to a duct capable of venting water vapor and odors into the outdoors. Mold growth within the bathroom or attic is a clear indication of improper ventilation that must be corrected in order to avoid structural decay and respiratory health issues.

More On Bathroom Fans and Ventilation

What to Know About Wood Burning Stoves

Wood burning stoves (also known as a wood stove) are heating appliances made from iron or steel that is capable of burning wood fuel. Unlike standard fireplaces, wood burning stoves are typically contained entirely within the living space, rather than inset in the wall.

stove4 220x300 What To Know About Wood Burning Stoves

Wood burning stoves come in many different sizes, each suited for a different purpose:

  • Small wood burning stoves are suitable in single rooms, seasonal cottages or small, energy efficient homes. These models can also be used for zone heating in large homes where supplemental heating is needed.
  • Medium-size wood burning stoves are appropriate for heating small houses or mid-size homes that are intended to be energy-efficient and as inexpensive as possible to maintain.
  • Large wood burning stoves are used in larger homes or older homes that leak air and are located in colder climate zones.

To ensure safe and efficient use of wood burning stoves, check out the following tips:

Never:

  • burn coal. Coal burns significantly hotter than wood, posing a fire hazard;
  • burn materials that will emit toxic chemicals, such as wood that has been pressure-treated or painted, colored paper, gift wrap, plastic, plywood, particleboard, or questionable wood from furniture;
  • burn wet wood. Generally speaking, it takes six months for cut, stored wood to dry out and be ready for use in wood-burning stoves;
  • burn combustible liquids, such as kerosene, gasoline, alcohol or lighter fluid;
  • let small children play near a lit wood-burning stove. Unlike standard fireplaces, the sides of which are mostly inaccessible, all sides of wood burning stoves are exposed and capable of burning flesh or clothing; or
  • let the fire burn while the fire screen or door is open.

Always:

  • use a grate to hold the logs so that they remain secured in the stove and the air can circulate adequately to keep the fire burning hot;
  • keep the damper open while the stove is lit;
  • dispose of ashes outdoors in a water-filled, metal container;
  • check smoke alarms to make sure they are working properly; and
  • periodically remove the stovepipe between the stove and the chimney so that it can be inspected for creosote. Homeowners may want to hire a professional to perform this service.

Wood Burning Stoves Efficiency and Air Pollutantsstovesmog What To Know About Wood Burning Stoves

While federal and state governments crack down on vehicle and industrial emissions, they do relatively little to limit the harmful air pollution emitted from wood burning stoves. The problem is so bad that, in many areas, such as Chico, California (pictured at right), the smoke from wood burning stoves is the largest single contributor to that city’s air pollution.  Smoke from wood burning stoves can cause a variety of health ailments, from asthma to cancer.

To mitigate these concerns, the EPA sets requirements for wood burning stoves and emissions based on the design of the stove: 4.1 grams of smoke per hour (g/h) for catalytic stoves, and 7.5 g/h for non-catalytic wood burning stoves. Some state laws further restrict airborne particulates, and many new models emit as little as 1 g/h. These two approaches — catalytic and non-catalytic combustion — are described briefly as follows:

  • In catalytic stoves, the smoky exhaust passes through a coated, ceramic honeycomb that ignites particulates and smoke gasses. Catalysts degrade over time and must eventually be replaced, but they can last up to six seasons if the stove is used properly. Inadequate maintenance and the use of inappropriate fuel result in an early expiration of the catalyst. These stoves are typically more expensive than non-catalytic models, and they require more maintenance, although these challenges pay off through heightened efficiency.
  • Non-catalytic stoves lack a catalyst but have three characteristics that assist complete, clean combustion:  pre-heated combustion air introduced from above the fuel; firebox insulation; and a large baffle to create hotter, longer air flow in the firebox. The baffle will eventually need to be replaced as it deteriorates from combustion heat.

The following indicators hint that the fire in wood burning stoves suffers from oxygen deprivation and incomplete combustion, which will increase the emission of particulates into the air:

  • It emits dark, smelly smoke. An efficient stove will produce little smoke.
  • There is a smoky odor in the house.
  • There is soot on the furniture.
  • The stove is burning at less than 300º F. A flue pipe-mounted thermometer should read between 300º F and 400º F.
  • The flames are dull and steady, rather than bright and lively.

To ensure efficiency, practice the following techniques:

  • Purchase wood burning stoves listed by Underwriters Laboratories. Stoves tested by UL and other laboratories burn cleanly and efficiently.
  • Burn only dry wood. Wood that has a moisture content (MC) of less than 20% burns hotter and cleaner than freshly cut wood, which may contain half of its weight in water.
  • Burn hardwoods, such as oak, hickory and ash once the fire has started. Softwoods, such as pine, ignite quicker and are excellent fire starters.
  • Make sure the stove is properly sized for the space. Wood burning stoves that are too large for their area burn inefficiently.
  • Burn smaller wood rather than larger pieces. Smaller pieces of wood have a large surface area, which allows them to burn hotter and cleaner.

Wood burning stoves, if properly designed and used appropriately for the space, are efficient, clean ways to heat a home.

 What To Know About Wood Burning Stoves

Dealing With Pet Allergies

Pet Allergens and What You Should

Pet allergens pose a health threat to certain individuals.

evil cat Dealing With Pet Allergies
 
Modes of Transmission

Cat dander consists of microscopic pieces of cat skin that have dried, flaked off and become airborne. Shed dander can land on and stick to bedding, curtains, carpeting, and other surfaces, including people’s skin and clothing. It contains Fel D1, a glycoprotein found in the cat’s sebaceous glands, located under their skin, and, to a lesser extent, it is found in cats’ saliva and urine. Fel D1 can cause rapid allergic reactions in sensitive individuals. Unlike cats, the dogs’ allergen, Can F1, is found in higher concentrations in their saliva than in their sebaceous glands.

Facts and Figures about Pet Allergens

  • More people are allergic to cats than they are to dogs. This may be due to the severity of the allergen Fe D1, or because dogs are generally bathed regularly, whereas cats are not.
  • Between 6 and 10 million Americans are allergic to cats, and approximately one-third of them have cats in their homes.
  • Animal dander, hair, and other organic debris in homes can also result in a significant increase in the level of dust mites, mite feces and other allergenic insect parts.
  • Allergens may be found months or years after a pet has been removed from a house.
  • Pet borne allergens commonly infiltrate places where pets have never been present, such as schools, workplaces, and other public spaces. Since dander allergens are sticky, they can be transported to these places on the clothing of pet owners.
  • Animal hair, despite popular belief, is not considered to be a significant allergen. However, hair can collect pollen, dust, mold, and other allergens.  sib Dealing With Pet Allergies
  • There are no “non-allergenic” breeds of dogs or cats. Some breeds of both species, however, are believed to be hypoallergenic; anecdotal reports claim that the Siberian, rex and sphynx cat breeds are less likely to provoke an allergic attack than most other cats. Similarly, dog breeds, such as poodles and schnauzers, have been reported to be less allergenic. None of these claims has been validated scientifically.

Cat and Dog Pet Allergy Symptoms

These include:

  • itching;
  • sneezing and congestion;
  • redness, itching, swelling and watering of the eyes;
  • post-nasal drip, itching or hoarseness, and the need to clear the throat often;
  • itchy rashes or hives;
  • itching, plugging or popping in the ears; and
  • coughing, wheezing, tightness in the chest, frequent bronchitis, and a shortness of breath.
How to Test If a Cat or Dog Has Been in a Building

A pet can be forbidden by many lease agreements, which may then be violated by tenants who secretly house cats or dogs. Also, cats may visit a residence at night to forage for food or gain shelter. The following detection methods may be used:

  • Smell for the animal. If the cat is an indoor cat, a litter box must have been used somewhere in the building, and they almost always produce an odor. Even after they are removed, the smell from a litter box may linger for quite some time. If a male cat was present in the building and he has urinated on or “marked” any areas, the odor will be very strong.
  • Look for hair. Somewhere in the building, especially where the cat likes to sleep or rest, there will be large amounts of hair.
  • Use a blacklight to check for pet urine.

Cleaning Tips for Buildings Previously Occupied by Cats and Dogs

Pet allergen cleanup by clients who are looking to buy a home but are concerned about the air quality in their prospective new home should take not of the following suggestions:

  • Obtain a thorough, professional duct cleaning.
  • Commercially steam-clean, professionally dry-clean, or use very hot water to launder clothing.
  • Wash and use a HEPA vacuum for interior surfaces. Note that ordinary vacuum cleaners, which cause allergenic particles to become airborne, are ineffective and may even worsen the problem for sensitive occupants.

Advice for People with a Pet

A combination of approaches—medical control of symptoms, good housecleaning and planning—is most likely to succeed in allowing an allergic person to live with a pet. For allergic people who won’t give up their pet, check out these following tips:

  • Take allergy medication. Most fall under one of the following three categories:
  • antihistamines, such as over-the-counter Claritin or Benadryl, or the prescription drugs Allegra or Zyrtec;
  • decongestants, such as OTC Sudafed or prescription Allegra-D; or
  • prescription steroids, such as Flonase or Nasonex sprays.
  • Get allergy shots. These are not always effective, however, and completing treatment can take years.
  • Bathe your pet on a weekly basis. Cats can get used to being bathed, but it’s critical to only use products labeled for them.dog pet sleep couch Dealing With Pet Allergies
  • Keep the pet outdoors as much as possible.
  • Allergic individuals should not hug, pet or kiss their pets.
  • Have your pet spayed or neutered. The allergen produced by a cat is highest in unaltered males and lowest in altered males.
  • Remove clothing worn after grooming or playing with pets.
  • Litter boxes should be placed in an area unconnected to the air supply to the rest of the home, and should be avoided by allergic individuals.
  • Design a cleaning regimen that can substantially reduce those levels, ranging from discarding materials to HEPA-vacuuming to washing certain surfaces.
  • Maintain adequate ventilation.
  • Remove as much carpet from the home as is feasible. The less dander-catching furnishings, such as cloth curtains and blinds, the better.
  • Clean frequently and thoroughly to remove dust and dander, washing articles such as couch covers and pillows, curtains and pet beds.
  • Create an “allergy-free” zone in your home—preferably, the allergic person’s bedroom—and strictly prohibit the pet’s access to it. Consider using impermeable covers for the mattress and pillows.
  • Keep pets off furniture, especially upholstered furniture where dander can be easily transferred.

Irritation and contamination caused by pet allergens can be limited by proper care of their hygiene, homes and owners.

Thanks to by Nick Gromicko and Rob London of InterNACHI

 Dealing With Pet Allergies