Merv 13 Filter

MERV 13 furnace filters

For allergies, asthma, and smoke season.

• Catches the finer particles a MERV 8 or 11 lets through
• Pollen, pet dander, mould spores, dust mite debris
• Helps with the fine particles in wildfire smoke
• The usual step up when someone in the house has trouble breathing
• Older furnace? Call us first. It isn't the right filter for every system.

What you need to know

Do I actually need a MERV 13?

For most homes, no. A MERV 8 or a MERV 11 gives you clean air without asking much of your furnace, and that's what we sell the most of.

Where a MERV 13 earns its keep is when someone in the house has allergies, asthma or another breathing condition, or when you live somewhere with a lot in the air. If that's you, the extra few dollars a filter is money well spent.

Will it be hard on my furnace?

It can be. A filter that catches more also slows the air down, and your blower has to push harder to move the same amount of air. On a newer system with well sized ducts, that's usually fine. On an older system, or one that already struggles on cold nights, it's worth thinking twice.

If you're not sure, ask the person who services your furnace. It's a thirty second question for them.

Does a MERV 13 stop smoke and viruses?

Partly, and it's worth being clear about this.

A MERV 13 catches a good share of the fine particles in wildfire smoke, which is why it helps during smoke season. What it does not do is remove the gases or the smell. For that you need a carbon filter, and that's a different product.

Same idea with viruses. Viruses travel on droplets and fine aerosols, and a MERV 13 captures a meaningful share of those as they pass through. It reduces what's circulating in your ducts. It is not a medical device and nobody should treat it as one.

How much more does it cost?

A MERV 13 usually runs a few dollars more per filter than the same size in MERV 11. On a one inch filter changed a few times a year, you're talking about the price of a coffee a month.

Can I trust the number on the box?

Not always, and this is the part most people don't know. Nobody checks it. There's no inspector and no rule that says a filter has to be tested before someone prints MERV 13 on the packaging.

Buy from manufacturers who put their name, their address and their country of manufacture on the box. Camfil is one of them, and it's the brand Canadian hospitals use.

So should I buy one?

Short version:

• Allergies, asthma, pets, or a smoky summer: go MERV 13.
• An older furnace or airflow you already worry about: stay at MERV 11.
• Neither of the above: a MERV 8 or 11 is plenty, and you'll save money.

Still on the fence? Call (888) 315-0105. We do this all day, and we'll tell you honestly if you don't need the more expensive one.