The best and most obvious allergy relief is to remove or reduce the amounts of allergens you breathe.
To reduce dust.
Clean you air ducts every 3-5 years. With a new home clean before moving in to remove sheet rock and wood sanding dust. Better filtration – dust will enter from the outdoors. To remove outdoors dust use HEPA filters in the home. Either room models HEPA filters or a whole house HEPA filtration unit that works in conjunction with your air ducts. Carpets also collect dust. When or if possible use hard surface flooring or clean the carpet every 3 months using a quality carpet cleaning service that extracts all water.
To reduce mold.
Keep a clean, dry crawlspace. Who ever goes in their crawlspace? If you don’t, like most people, it would be wise to call and have someone inspect and assess the crawlspace. No open soil, no wet block walls, no condensation on the air ducts. A dry crawlspace means less mold not just in the crawlspace but less mold in the home, over time as much as 30% of the crawlspace air can infiltrated the home. Keep your HVAC coil clean, mold growth in this dark wet area and then when the blower comes on it will blow the mold and mold odors into the living spaces. Keep a dry basement, not just dry but with low humidity. All indoor air quality organizations agree that 45%-55% relative humidity prevents mold while providing human comfort. Less that 30% can cause dry eyes and dry sinuses cavities. When lowering humidity for mold, 45-55% will do. To remove outdoors mold spores that nature constantly produces use HEPA filters in the home. Have a professional assessment if you are not sure to use a room model or whole home unit. Air testing and a quality inspection provide the best information specific to your home on what can be done to lower the mold spore counts.
To reduce dust mites.
Remove carpets, because carpets collect dust. When or if possible use hard surface flooring or clean the carpet every 3 months using a quality carpet cleaning service that extracts all water. Keep the humidity low, dust mite population go up with higher humidity levels. All the water a dust mite needs is humidity in the air. Low humidity, again 45-55%, and the dust mite population drops. You still need to remove the residual dust mites. Use a good vacuum that has a HEPA filter and use HEPA air filters in the home. Either rooms models HEPA filters or a whole house HEPA filtration unit that works in conjunction with your air ducts.
To reduce Chemical gases (VOCs Volatile Organic Compounds)
Store chemical outdoors. Use low VOC cleaners in your home. Choose low VOC paints. Choose low VOC Flooring. Every new home starts out with elevated VOCs. All the manufactured plywood’s, OSB board, cabinets, wood flooring, carpet, furniture, and flex ducting have increased VOC counts. Only time and ventilation removes the VOCs. This take 2-3 years. During that time, you can use a HEPA filter with a VOC carbon reduction filter to lower the VOCs. The filter will need to be change frequently to keep removing the VOCs (Monthly for the first 3 years).
To reduce other particulates.
Pet dander, pollen, grasses, etc. Use a good vacuum that has a HEPA filter and use HEPA air filters in the home. Either rooms models HEPA filters or a whole house HEPA filtration unit that works in conjunction with your air ducts. Clean your air ducts every 3-5 years.