Nick Baker
A Homeowners Guide to Furance Filters: Types and Selection
What kind of furnace filter should I buy?
As a homeowner, maintaining a comfortable and healthy living environment is a top priority. One key component to achieving this goal is selecting the proper furnace filter. Furnace filters play a crucial role in improving indoor air quality, reducing energy consumption, and extending the life of your HVAC system. This blog post will help you understand the different types of furnace filters and guide you in selecting the one that is best suited for your needs.
Fiberglass Filters

Fiberglass filters are the most basic and affordable option. They are made from spun glass fibers arranged in a flat panel design. These filters have a low Minimum Efficiency Reporting Value (MERV) rating, usually ranging from 1 to 4. This means they are primarily designed to protect the furnace from large particles like dust and lint, rather than to improve air quality.
Pros:
Inexpensive
Easy to replace
Cons:
Minimal air filtration
Frequent replacement required (usually every 30 days)
Best for: Homeowners on a budget who don't have specific air quality concerns.
2. Pleated Filters (Most Popular)

Pleated filters are made from polyester or cotton fibers folded into pleats to increase their surface area. These filters have a higher MERV rating, typically between 5 and 13, providing better filtration of smaller particles like pollen, mold spores, and pet dander. The increased efficiency does come at a slightly higher price, but the benefits may be worth it for those with allergies or respiratory issues.
Pros:
Improved air quality
Better particle filtration
Longer lifespan (usually 60 to 90 days)
Cons:
Slightly more expensive
May require more frequent replacement in high-dust environments
Best for: Homeowners seeking better air quality, especially those with allergies or respiratory issues.
3. High-Efficiency Particulate Air (HEPA) Filters

HEPA filters offer the highest level of air filtration, with MERV ratings of 17 to 20. They are made from a dense network of fibers that can capture particles as small as 0.3 microns, effectively removing bacteria, viruses, and smoke from the air. However, these filters are not typically designed for residential furnaces, as they require a specific system capable of handling the increased air pressure.
Pros:
Superior air filtration
Ideal for removing allergens, bacteria, and viruses
Cons:
Expensive
Requires a compatible HVAC system
Best for: Homeowners with severe allergies or compromised immune systems, or those living in areas with high pollution.
4. Washable Filters

Washable filters, also known as reusable or permanent filters, are made from materials like foam or aluminum mesh that can be cleaned and reused. Their MERV ratings vary, usually between 1 and 8. While these filters are more eco-friendly and cost-effective in the long run, they may not provide the best air filtration for those with specific health concerns.
Pros:
Environmentally friendly
Cost-effective over time
Cons:
Initial cost is higher
Less effective air filtration compared to pleated or HEPA filters
Best for: Environmentally-conscious homeowners without specific air quality needs.
Selecting the right furnace filter depends on your budget, air quality needs, and HVAC system compatibility. In general, pleated filters offer a good balance of performance and cost for most homeowners, while those with more specific health concerns may benefit from investing in a HEPA filter system. Remember to check and replace your filter according to the manufacturer's recommendations to ensure optimal performance and maintain a healthy living environment in your home.