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How Healthy Humidity Levels In Your Home Can Protect You

Thursday, September 12th, 2019

A healthy humidity level inside your home doesn’t just happen naturally. Just as you usually wouldn’t be comfortable simply letting the indoor temperature match outdoor readings, leaving indoor humidity to chance isn’t a strategy for a healthy, comfortable indoor environment, either.

The interaction between water vapor in the air and a healthy home occurs at both low and high humidity levels.

  • Airborne particulates like bacteria, spores and viruses are more active at certain humidity levels. Colds and flu viruses, for example, actually thrive in dry environments where relative humidity is 35% or lower. Mold spores and active mold growth, conversely, as well as certain bacteria types, are activated when humidity rises above 50%.  When humidity is maintained within the 35% to 50% target range, allergic symptoms, respiratory illness and other heath issues may be reduced.
  • Indoor humidity is also linked to increased levels of gases known as volatile organic compounds (VOCs). These substances—formaldehyde is the best-known example—are ingredients in many building materials as well as carpeting, paint and furniture. When exposed to indoor humidity above 50% for extended time periods, many of these products emit higher levels of VOCs into the air you breathe. Long-term exposure to volatile organic compounds is a known health risk.  

When Humidity Is Too Low …

Low indoor humidity often occurs in dry winter conditions. Gas-fired heating dries indoor air further, causing humidity levels to drop into the unhealthy range. Use of individual room humidifiers—or installing a whole-house humidifier that adds water vapor to the HVAC airflow to maintain precise indoor humidity levels—are the best recourse to keep the indoor environment healthy.

When Humidity Is Too High …

Indoor humidity above 50% is often related to a naturally humid outdoor climate. To keep the indoor environment drier and healthier, these methods are helpful.

  • Air-sealing the home to reduce infiltration of moist outdoor air.
  • Installing a whole-house dehumidifier in the HVAC system to control humidity.
  • Annual maintenance check-up of the central air conditioner to ensure that the unit’s humidity extraction function is operating up to specs.
  • Installing exhaust fans in kitchens and bathrooms where water vapor originates.

Moist Home? Your Health May Be At Risk…

Thursday, September 5th, 2019

Excessive moisture can turn your home into an unhealthy—not to mention uncomfortable—living environment. Chronic indoor dampness may simply result from high levels of water vapor in the air or from persistent sources of moisture that aren’t properly identified and resolved. The Environmental Protection Agency recommends that indoor humidity should ideally stay below 50% most of the time and never exceed 60%.  When indoor dampness frequently rises above that level, the risk of certain health issues likewise increases.  

Some of the health-related consequences of a damp house include

  • Mold and mildew. Fungus including toxic mold and mildew require moist conditions to activate and spread. Airborne spores released by growing mold fed by high indoor moisture levels may trigger allergies and even serious illness when inhaled by occupants.  
  • Dust mites. Tiny dust mites thrive in moist indoor environments where humidity reaches 60%. Easily stirred up into the air by human activity, these insects are a frequent cause of nagging allergic responses.
  • Pests and vermin. Many unwanted and unhealthy creatures are attracted to chronically damp conditions inside a house including disease-carrying rodents, mosquitoes and parasitic worms.  

To get a handle on dampness, consider these frequent contributors to unwanted indoor moisture:

  • In locales where outdoor relative humidity frequently exceeds 50%, excess humidity may infiltrate the house through structural cracks and gaps.
  • Rooms that produce high water vapor such as the kitchen and bathroom require exhaust fans to remove damp air.
  • A professional roof inspection of the exterior of the roof as well as inside the attic can identify hidden leaks that cause chronic moisture.
  • Ongoing leaks in plumbing lines routed through areas such as the crawl space or basement can create a continuous source of dampness.  
  • In locales with a high natural water table, rising groundwater can keep the crawl space chronically wet or push water into the basement through foundation cracks.
  • Air conditioner issues such as short-cycling, low airflow or insufficient refrigerant charge may inhibit proper extraction of water vapor from the air.

How to Manage Humidity in Your Home this Summer

Tuesday, June 18th, 2019

High outdoor humidity is a fact of life during summer in many locales. Often, it doesn’t stay outdoors. In addition to being a source of discomfort to occupants, persistent indoor humidity degrades building materials and triggers growth of toxic mold. Because your air conditioner runs longer to maintain indoor comfort when humidity is high, monthly cooling costs are also elevated.

How High Is Too High?

The Environmental Protection Agency (EPA) recommends maintaining the indoor humidity level at a range of 50% to 60%. During summer, most locations in the U.S. exceed that level in either morning or afternoon measurements. Therefore, special effort is required to keep the indoor environment less humid than outdoors. Here are some things you can do to reduce excessive humidity in the house this summer:

  • Maintain the air conditioner. Indoor humidity control is an important function of the air conditioning process. Dry air cools more efficiently than humid air. Schedule annual professional A/C maintenance including servicing the indoor evaporator coil that extracts water vapor from air and checking refrigerant charge to ensure optimum humidity reduction. Also, change the air filter monthly to keep system airflow up to specs.
  • Air seal the house. Outdoor humidity naturally migrates into drier zones indoors. Small cracks and gaps in the structure of the house allow humid air to leak into the interior and raise indoor levels. Check the weatherstripping around doors and windows and replace if its worn or missing. Look for cracks in the structure around exterior walls and gaps along the baseboard; seal with silicone caulking.
  • Exhaust humid rooms. High levels of water vapor in kitchen and bathrooms are common and should be controlled with ceiling exhaust fans. Make sure the fan exhaust duct extends all the way to the exterior of the house, not just into the attic.
  • Install a whole-house dehumidifier. These units, connected to your central HVAC ductwork, automatically extract water vapor from the system airflow to keep indoor humidity levels at the desired setting. All air circulating through the entire house is continuously dehumidified as long as the system is running.

How to Keep Indoor Humidity High Enough in Winter

Tuesday, February 19th, 2019

Cold weather outdoors and low indoor humidity seem to go hand-in-hand. It’s a natural fact of physics that cold air doesn’t retain moisture as efficiently as warm air. Thus, winter months tend to be periods of reduced humidity. Generally speaking, humidity inside the house should average around 40% if possible, year-round. When levels drop below that comfort zone, however, a number of consequences occur:

  • Physical symptoms such as dry skin and scratchy throat are common.
  • Airborne viruses like cold and flu thrive longer in dry air and are thus more likely to infect occupants.
  • Annoying static electricity shocks occur frequently.
  • Because the house feels colder in low humidity, furnace thermostat settings are often adjusted upwards to compensate and heating costs rise. Forced air furnaces also remove some humidity from the air, further exacerbating the dry conditions.
  • Shrinkage and splitting may occur in wooden components such as flooring and cabinetry.

Preserving a comfortable, healthy indoor environment in winter requires some pro-active steps to compensate for the dry conditions outdoors.

  • Outside air seeping inside contributes to overly dry conditions in a house during winter. Seal air leaks to prevent infiltration of cold, dry air. Renew worn weatherstripping around doors and windows. Locate cracks and gaps in exterior walls and the ceiling and fill with caulking.
  • Consider adding a whole-house humidifier. Installed inside your HVAC ductwork, the unit continuously monitors indoor humidity and automatically adds water vapor when required to maintain the desired setting. Because the entire indoor air volume circulates through the ductwork multiple times each day, consistent humidity control throughout the entire home is assured. Plumbed directly to the household water system, these units operate continuously and do not require user effort such as adding water or cleaning.
  • Room humidifiers add humidity to limited individual spaces (such as a bedroom). These portable units can be moved from room-to-room if necessary. Most models include a water reservoir which must be manually refilled, usually on a daily basis.

How and When to Use a Humidifier Indoors

Tuesday, October 16th, 2018

room humidifierBecause dry air is far more common during winter in most parts of the country, that’s usually the time of year when most people consider adding a humidifier to their home. The most common motivation is relief from physical symptoms—itchy skin, sore throat, dry eyes, cough and other discomforts are associated with low humidity. Indoor humidity below 50% is proven to promote replication of airborne viruses including cold and flu. Other household issues also arise: painful zaps from static electricity are more frequent and wooden building materials such as hardwood floors tend to shrink, causing gaps between planks and splintering.

How Dry Is Dry?

The Environmental Protection Agency recommends keeping indoor humidity levels between 30 and 60 percent. Humidity dropping below 30% will often cause one or more of the above dry air symptoms. Humidity above 60%, conversely, degrades indoor comfort and raises a different set of health concerns such as mold and mildew become an issue

Once the need to raise indoor humidity is established, you have two options:

Room Humidifiers

These units add humidity to the air in limited enclosed spaces. They are free-standing, generally portable and require addition of water to the reservoir tank on a daily basis, as well as periodic cleaning. Small room humidifiers can treat rooms up to 300 square feet, while the largest models placed centrally inside a home can handle up 1,000 square feet.

Room humidifiers are typically available in two types:

  • Warm mist models include a heating element to boil water in the reservoir into steam, which is then released as water vapor directly into the air.
  • Cool mist units emit a stream of room-temperature mist composed of ultra-fine water particles.

Whole House Humidifiers

Mounted directly inside your home ductwork, these units add humidity directly into the HVAC air flow that circulates throughout every room in the house. Most are directly plumbed to a household water line and require no refilling or other daily user input. Automatically operated by a wall-mounted humidistat—much like a thermostat—the whole house humidifier allows precision setting of desired humidity in the entire residence.

4 Situations Where Using a Humidifier Makes Sense

Tuesday, June 5th, 2018

humidifierAccording to the Environmental Protection Agency, the household humidity level should ideally range between 40% and 60%. Due to seasonal changes and other factors, however, the “ideal” may be hard to maintain. In winter, outdoor air is naturally drier and forced-air heating installed in most homes lowers humidity even more. During summer, extended use of the air conditioner also extracts humidity from the air and may overly dry the indoor environment. A humidifier can help restore balance and keep household levels within the EPA-recommended range. Here are some scenarios where use of a humidifier makes sense:

  • When you experience dry skin. Dry air often results in dry, chapped skin that itches and causes other irritations. Restoring proper humidity to the air is often a more long-term solution than using topical skin lotions that offer only temporary relief.
  • When allergy symptoms occur. When air is excessively dry, certain microscopic allergens such as common dust, mold spores and lint particles are more likely to be stirred up and remain airborne where they may be inhaled. Increasing humidity generally keeps airborne particulate counts lower.
  • When your home is getting creaky. Older houses are often affected by conditions of chronic low humidity. Building materials shrink and split over the years as wood naturally dries out. Paint also dries up and flakes and caulking that seals windows and other joints becomes hard and deteriorates. Squeaky wooden floors are another sign of a dry environment and resultant shrinkage may also cause gaps between floorboards. A humidifier keeps humidity levels more consistent in all seasons and prevents drying of wooden structure.
  • When static electricity is a problem. When indoor air is overly dry, an electrostatic charge builds up as you walk across materials like carpeting or slide across a sofa. Touching a conductive surface like a doorknob then zaps you with a shock that is painful and annoying. Higher indoor humidity causes static electricity to naturally dissipate and makes daily life less shocking.

What Window Condensation Tells You About Your Home’s Humidity

Friday, December 22nd, 2017

window condensationOne way to tell if your home needs humidity control is to look out the window. Condensation on window glass in the form of droplets or fog can be a warning sign that indoor humidity levels are trending high. Water vapor in the air naturally condenses when it contacts any surface colder than the dew point. On a chilly winter day, the inside of window glass is typically one of the coldest exposed surfaces in the house.

Condensation on windows creates two immediate problems:

  • Wooden window frames and sills that are frequently wet due to condensation run-off often harbor mold growth and prematurely deteriorate.
  • Moist, dripping glass always looks streaked and spotted and is difficult to keep clean.

Window condensation can also represent a more serious long-term red flag, however. While glass usually provides an early signal of indoor condensation, it’s not the only spot where it occurs. Warm, overly humid indoor air seeping into cold exterior wall cavities during winter, for example, may condense and trigger toxic mold growth concealed inside the wall. Also, heated air rising in living spaces may penetrate the ceiling and condense as it enters the cold attic, saturating attic insulation and activating mold.

Home humidity control to reduce condensation involves keeping humidity at the lower end of the recommended range of 30% to 50%. Here are ways to make it happen:

  • Vent humid rooms. All bathrooms plus the kitchen should have vent fans that remove humid air and vent it to the outside through dedicated ducts.
  • Install a whole-house dehumidifier. Mounted inside your heating/cooling ductwork, these units continuously sense indoor humidity and maintain it to the setting entered on a digital humidistat. Permanently plumbed into the household drain system, they require no daily user maintenance.
  • Consider a heat recovery ventilator. An HRV provides balanced fresh air ventilation in winter without opening windows. Incorporating a central heat exchanger, the unit recovers up to 70% of heat from indoor air before it is exhausted, then transfers that heat to incoming cold fresh air.

For more about home humidity control to prevent mold contamination, contact Rytech, Inc.

How To Control Extreme Humidity In Your Home

Thursday, October 26th, 2017

excess humidity
Humidity control helps preserve the house and its contents, as well as keeping the indoor environment healthier. Because today’s homes are built to higher energy efficiency standards, they are very tightly sealed. This means accumulating water vapor can rise to extreme levels that cause ongoing damage such as warping/rotting wooden structural components and peeling paint as well as triggering growth of toxic mold. Overly humid homes also feel hotter in summer and clammy cold in winter, raising cooling and heating costs.

The Environmental Protection Agency recommends maintaining indoor humidity “ideally between 30% and 50%.” Here are some methods of humidity control to keep your house in the ideal range.

  • Exhaust humid rooms. Bathing and cooking are sources of high indoor humidity. Exhaust fans should be installed in bathrooms and kitchen to vent water vapor through dedicated ducts all the way to the exterior of the house. Also make sure the clothes dryer is adequately vented to the outdoors and the vent is regularly cleared of lint.
  • Maintain your HVAC system. A forced-air furnace helps dry out humidity in winter and an air conditioner extracts water vapor during summer. Proper airflow through the system is critical to this process so make sure the filter is changed regularly in all seasons and that HVAC ductwork is intact and does not leak conditioned air.
  • Check the crawlspace. Rising groundwater that keeps soil under the house chronically moist can form a source of water vapor that migrates up into living spaces. Installing a vapor barrier to contain soil moisture reduces humidity infiltration. Also look for ongoing plumbing leaks as well as uninsulated pipes that “sweat” and produce large amounts of condensation.
  • Consider a whole-house dehumidifier. Installed in your HVAC ductwork, the system continuously senses humidity level in the airflow and extracts excess water vapor. Because all air volume in the house passes through the ductwork multiple times daily, comprehensive humidity control is achievable. These units are permanently plumbed into the household drain system and require only annual cleaning.

Prevent moisture damage and mold with effective humidity control.

Understanding the Process for Home Mildew Removal

Tuesday, June 24th, 2014

mildew removalSooner or later, homeowners may need some advice about mildew removal. While many varieties of mold can grow in a household environment, mildew is certainly the most common. However, its familiarity doesn’t reduce the potential for damage, health consequences and/or just very unsightly appearance.  (more…)

Understand How Moisture Enters Your Home and Builds Up to Create a Problem

Wednesday, September 25th, 2013

moisture-condensation in homeIt’s about the path of least resistance for moisture, which will seep or flow into your home from cracks in the walls and other openings. You may also find it condensing on windows and pipes or collecting from steam due to a lack of ventilation. (more…)