Reducing Spring Allergies in an Energy-efficient Home

The arrival of spring for many of us signals a return to the garden and hiking trails. Unfortunately, for some, it also signals the return of seasonal allergy symptoms. Pollen counts are currently at medium to high levels in most of the United States. Tree pollens, such as birch, ash, maple, and oak, are especially prevalent now, becoming airborne and leaving a noticeable layer of pollen dust on cars and waterways. Humidity levels are also on the rise, boosting dust mite populations and mold growth.

When pollen grains, dust mite droppings, or mold spores enter the nose of someone who is allergic, it can trigger a strong reaction. The immune system mistakes the pollen for an invader, and an immune reaction is triggered, causing a runny nose, itchy eyes, sneezing, and other symptoms.

Unfortunately, many allergy medications, such as antihistamines, nasal sprays, and decongestants, have side effects, including drowsiness, dizziness, and stomach problems. Some allergy sufferers find relief from natural treatments, such as stinging nettle, a neti pot, and quercetin.

Many allergy sufferers stay cooped up in their homes, remaining indoors during times of high pollen counts, with the windows closed. Window fans, although energy efficient, are not recommended because they bring more pollen into the home. You may have the urge to air out your home in the spring; however, this is not recommended for allergy sufferers, unless a heat recovery ventilator (HRV) is used.

Some allergy sufferers have found relief from symptoms using an HRV. Unlike air purifiers that filter air in one room, the HRV system filters the intake air coming into the entire home before dispersing it. The filters can remove many common allergens, including pollen, dust, and even pet hair, in addition to regulating humidity levels, therefore preventing mold and mildew issues while keeping dust mite populations down. The HRV filters are most effective when cleaned or replaced periodically; thus it is important to have a system where the filters are easy to access for optimum maintenance.

Zehnder HRVs are commonly installed in highly energy efficient homes to provide a continuous stream of fresh air throughout the year. We have one in our home in the Belfast Cohousing & EcoVillage in Maine.  Standard filters (MERV 7 to 8) remove pet dander, pollen, dust mites and droppings, auto emission particles, and lead dust, and the optional finer filter (MERV 13) removes even smaller particles.   The filters are easy to remove from the unit to either vacuum or replace.

Another helpful approach is to remove existing allergens from the home environment and discourage their accumulation. Use a vacuum equipped with a HEPA filter, avoid having wall-to-wall carpeting as it traps dust and pollen, wash bedding regularly, and clean out household vents and air ducts to avoid dust, pollen, and mold accumulation.

“I have a morning regimen where I check the pollen count, weather, and air quality,” explains Haven McClure, a life-long allergy sufferer and asthmatic. “Generally my nose will tell me more than anything else. I wear a vogmask during periods with a high pollen count, particularly in the morning.”

Another helpful tip is to be aware of when pollen is most prevalent. Pollen counts are highest on warm, windy days and lowest just after rain; thus it is helpful to consider this before opening windows and spending extended time outdoors. Avoid the urge to air out the home, particularly when pollen counts are high unless you are using an HRV system to bring fresh air into the home, or at least a window filter.

Some window air conditioner units are somewhat helpful if they contain a high-quality filter and it is cleaned or changed regularly, although outside air can leak in through cracks. Central air conditioning can be somewhat helpful, although it may constantly pull in outside air. And beware of allergens and mold collecting in the air ducts. Have the ducts cleaned annually, replace the filters, and use recycle mode to avoid bringing in outside air.

Air conditioners, dehumidifiers, and HRV systems can all be helpful at reducing moisture levels in the home, thus mitigating dust mite populations and mold growth. Air conditioners and dehumidifiers use a lot of electricity, while HRV systems are very energy efficient. Note that none of these appliances will stop an existing mold problem that has already infiltrated walls or will prevent a mold problem from developing if there is a water leak. They will, however, help keep moisture levels in a healthy range, preventing a problem from arising.

Be aware that mowing the lawn or raking can stir up large amounts of pollen. When you have spent extended time outdoors, wash your hair in the evening to avoid bringing pollen into your bed. If you are allergic to grass, keep the grass cut below two inches to prevent it from releasing pollen or replace the grass in your yard with allergen-free plants.

If you know which types of pollens trigger a reaction, you’ll know when you most need to limit your exposure to mitigate symptoms. Although tree pollen season is coming to a close this month, grass pollen season is approaching. At the end of the summer, weed pollen levels peak.

“You’re never going to eliminate 100 percent of your exposure to pollens, and in many ways, it’s not necessary,” explains McClure based on his personal experience. “What I’ve found is that if I reduce exposure, after a while, even on high pollen days, I won’t have a need to wear a face mask because I’ve built up immunity naturally without using allergy shots.”


Sarah Lozanova is a regular contributor to environmental and energy publications and websites including Mother Earth Living, Mothering, Energy International Quarterly, ThinkGreen.com, Triple Pundit, CleanTechnica, Green Business Quarterly, Natural Home, GreenBiz, Renewable Energy World, Windpower Engineering, and Solar Today.  She currently lives with her family in the Belfast Cohousing & Ecovillage.