MERV 8 vs MERV 13 Air Filters: What’s the Difference?
- Feb 10
- 4 min read
When it comes to MERV 8 vs MERV 13 air filters, more isn’t always better. Indoor air quality upgrades have to balance filtration performance with airflow and equipment health.
Many facility managers boost building filtration without confirming HVAC capacity first—and run into serious problems later.
In this guide, we dive into the technical differences between MERV 8 and MERV 13 air filters so you can choose the right option for your building—risk-free.
What is a MERV Rating?
MERV stands for Minimum Efficiency Reporting Value. The MERV rating system measures how well air filters remove particles of different sizes.
MERV ratings range from MERV 1-16
Higher MERV ratings capture more types of particles
Higher ratings also increase airflow resistance
Filters are tested under controlled conditions to earn their MERV rating
MERV Scale
Feature | MERV 8 | MERV 13 |
Particle Size Captured | 3.0–10.0 microns | 0.3–3.0 microns |
Dust & Lint | ✔ Yes | ✔ Yes |
Pollen & Mold Spores | ✔ Yes | ✔ Yes |
Fine Particulates (PM2.5) | Limited | ✔ Yes |
Bacteria | Limited | ✔ Yes |
Aerosols That May Contain Viruses | ✖ No | ◐ Partial |
Pressure Drop | Low | Moderate to High |
Energy Impact | Minimal | System dependent |
System Compatibility | No verification required | Verification required prior to installation |
What Particles Does a MERV 8 Filter Capture?
MERV 8 air filters are common in commercial HVAC systems because they offer reliable filtration and very minimal airflow resistance.
MERV 8 filters are proven to capture:
Dust and lint
Pollen
Mold spores
Large airborne particles
Types of Facilities That Typically Use MERV 8
Office buildings
Retail establishments
Warehouses
Many older buildings
Most older rooftop units (RTUs)
Because MERV 8 filters have low pressure drop, they put less strain on fan motors and help buildings maintain airflow and energy use.
What Does a MERV 13 Filter Remove from the Air?
MERV 13 air filters offer much higher filtration efficiencies, particularly for smaller airborne particles.
In laboratory testing, MERV 13 filters have been shown to capture:
At least 90% of particles between 1.0 and 3.0 microns
At least 50% of particles between .3 and 1.0 microns
Does MERV 13 Kill Viruses?
MERV ratings measure filtration efficiency based on particles. Bacteria and virus particles are far too small to be captured by a MERV filter.
There is one caveat to the above statement. Virus laden aerosols produced when people cough or sneeze will attach to larger particles that ARE captured by MERV filters. Here is a more detailed explanation.
MERV 13 filters are capable of capturing:
Common airborne particulates (dust, lint, pollen, mold spores)
Fine particulate matter (PM2.5)
Smoke
Many types of bacteria
Airborne virus-containing aerosols when they attach to larger particles
Why Does This Matter?
MERV 13 filters provide:
Higher static pressure
Greater fan horsepower requirements
Potentially lower airflow across coils and throughout the building
If your HVAC system isn’t designed or verified for MERV 13 filtration, these factors can contribute to:
occupant complaints about being too hot or too cold
increased electricity use
fan motor overheating
HVAC not working evenly throughout the building
shorter lifecycle for your HVAC equipment
Proper filtration upgrades require testing and verification. They shouldn’t be based on guesswork.
MERV Ratings: Which One Should You Choose?
If your HVAC system was designed with MERV 13 filtration in mind or has been properly tested and verified for use with MERV 13 filters, there is likely no reason to continue using MERV 8 filters.
When in doubt, it’s safer to stick with MERV 8.
If you’ve never verified fan capacity and static pressure at MERV 13 filtration levels:
Don’t upgrade filtration!
It could do more harm than good!
MERV Ratings: Filter Replacement
MERV 8: Every 3-6 months
MERV 13: Every 2-3 months
Because MERV 13 filters restrict airflow more than MERV 8 filters, they typically need to be replaced more frequently. How often you change your filters depends on:
Amount of traffic in the building
How much outside air your system uses
Quality of air around the building
MERV rating
Actual depth of the filters
Color of the filter rack
Instead of guessing when to change filters based on time, monitor filter pressure drop and change them when necessary.
The Bottom Line: MERV 8 vs MERV 13
MERV 8 vs MERV 13 isn’t about choosing the highest number.
When done incorrectly, upgrading your building’s filtration can damage equipment, waste energy, and degrade comfort.
It’s about choosing the right filter for your system.
Don’t risk damaging your HVAC system. Talk to a Specialist.
FAQs
Do I need MERV 13 filters?
That depends on your HVAC system. Many systems are not designed to handle HEPA filters. Doing so could decrease airflow and potentially damage your equipment.
Does MERV 13 use more energy?
It can. Restricted airflow typically requires more energy to push air through the system.
Who requires MERV 13 filters?
It depends on the type of building, local building codes, and how the building is being used. Using MERV 13 filtration does not automatically improve indoor air quality.
Can I upgrade my building filters to MERV 13?
We recommend against it unless you have verified fan capacity with a qualified HVAC technician.
Will MERV 13 filters improve IAQ?
MERV 13 filters can improve indoor air quality if proper attention is given to airflow restrictions.
Can I just replace my filters with MERV 13 and be done?
No. Replacing your building filters with MERV 13 without properly ventilating your system could damage your HVAC equipment.
Is MERV 13 better than MERV 8?
MERV 13 removes more contaminants from the air. However, if your system isn’t designed to accommodate MERV 13 filters, it will likely restrict airflow and put more strain on your HVAC system.
Will switching to MERV 13 filters save me money?
Not necessarily. Higher MERV ratings can increase energy use if your HVAC system isn’t designed for them.
Does MERV 13 increase electricity usage?
Possibly. Higher MERV filters increase air pressure which can cause your fan motors to use more electricity.
Is MERV 13 good for HVAC?
MERV 13 can work well if your HVAC system has been designed or evaluated for those types of filters.
How do I know what MERV rating to use?
Contact Burban Air Systems and we’ll help you to determine what MERV rating is best for your building.
