How Many Air Purifiers Do I Need: One For Every Room? Really?

A single air purifier unit won’t be enough to take care of the atmosphere of an entire house. If you got multiple rooms, and you want to ensure healthy and harmless air is spreading into the air, and ask yourself how many air purifiers do I need, this article will help you decide.

While one for every room might not always be necessary, in some cases, there will be no alternative. The number of air purifiers required to clean the atmosphere of a house properly depends on factors the size of the house, type of purifier, CADR rating, pollutant type, etc.

However, you’ll need to have a good understanding of how these factors come into play to assess the correct number of air purifiers you need for your house. So stick to the end of this article to get all the tips and knowledge necessary about this topic.

One For Every Room: Doesn’t It Seem Excessive?

A good quality air purifier can cost a good amount, especially the higher the capacity, the higher its price will go. So, should you have an air purifier in each room? It sounds a bit extravagant, right? 

In reality, you probably won’t need one purifier for each room of the house. But it might be necessary if the rooms are larger than standards or if you’re using HEPA filter purifiers.

Many other factors need to be considered when determining how many air purifiers should you have in your home. Overall, you’ll need to prepare a proper plan as well as a good understanding of the purifier’s capacity that you’re about to buy. 

In fact, a strategic purchase of products and placement can save you from a lot of unnecessary expense and hassle while having effective purification.

Keep an eye out for the CADR rating of a purifier. It can greatly help with assessing questions like how many air purifiers you need for your apartment.

For air purifiers, the higher the CADR value, the better. It’s measured by multiplying the cubic feet volume of air the purifier blows per minute with the purifier’s efficiency.

As air keeps getting contaminated continuously, the purifier must be apposite of CADR value to keep a large room’s atmosphere constantly pristine. Therefore, the larger the room, the higher the value should be.

How Many Air Purifiers Do You Need Basing on CADR Rating

The table below will give you an idea of what CADR rating purifier (HEPA filter) will cover what amount of area in an ideal setting.  

Room Dimension (ft x ft)Total Volume (cubic ft) (Ceiling height 9 ft)Suitable CADR valueRecommended No. of Purifiers
36324261 purifier, small
49441361 purifier, small
64574461 purifier, small
81729591 purifier, small
100900731 purifier, small
1211089881 purifier, small
14412961051 purifier, medium
16915211231 purifier, medium
19617641421 purifier, medium
22520251631 purifier, medium
25623041861 purifier, large
28926012102 purifiers, medium or 1 purifier, large
32429162452 purifiers, medium or 1 purifier, large
36132492682 purifiers, medium or 1 purifier, large
40036002982 purifiers, medium or 1 purifier, large
44139693352 purifiers, medium or 1 purifier, large

It is apparent that as the size of the room keeps increasing, so does the recommended CADR rating. People often ask, can you use two air purifiers in the same room? If the room is large enough, you may have to.

Another important thing to notice is, for rooms larger than 2600 m3 volume, the table suggests 2 medium purifiers or 1 large purifier.

In such cases, getting 2 medium purifiers will be a more effective choice for cost-efficiency and better cleanliness.

Impact of Different Purifier Types on Determining the Required Number of Purifiers

Although purifiers with HEPA filters are considered the most effective type, using other types can give you an upper hand in certain situations. Let’s take a look at how different types of purifiers determine how many of them you’ll need in your home.

  • HEPA Filter Air Purifiers

For an average-sized house, you’ll probably need one HEPA purifier for every room.

HEPA purifiers use a fan to draw the air in and then filter it into three distinct layers. The greater the number of pollutants in the air contains, the less amount of air these filters can process at a time.

Another issue with HEPA filters is that they can’t work effectively across rooms, even if you keep the door open. But the good news is that these purifiers are not that costly, especially the small or medium ones.

If you get one small or medium-sized purifier for each room that you spend the most time in, you can enjoy a fresh and healthy atmosphere almost all the time.

  • PCO Air Purifiers

Unlike HEPA filter purifiers, PCO purifiers have a larger range and don’t require to be placed in every room.

One PCO air purifier can easily maintain a large estate-sized room or 3 average-sized rooms at a time. In addition, if you leave the purifier room door open, a PCO purifier will effectively clean the air of the adjacent rooms as well.

  • Ionizers and Electrostatic Air Purifiers

A lot of people confuse ionizers and electrostatic air purifiers as being the same type. But in reality, they’re quite different. They both purify air via ionized particles, but the mechanism is different.

These purifiers have a great working range, like the PCO purifiers. A medium-sized ionizer can clean the air of up to 3000 sq ft. area with an average height ceiling.

And as ions flow with the air until they attach themselves to a pollutant, ionizers can clean adjacent rooms with the dispersed ions. But, of course, the doors must be kept open.

Besides a greater range, ionizers are also easier to maintain. But the problem is these ions can cause unwarranted chemical reactions with various materials in the air and generate toxic materials.  

Impact of Some Important Factors on Determining the Required Number of Purifiers

Besides types of purifiers, there are several other important factors that should come into play when you’re planning to buy purifiers for your house.

Considering these factors will help you get a cost-effective and efficient purifier setup for the whole house. Let’s dive in.

  • Covering the Important Rooms

You don’t spend an equal amount of time in every room of your house. Some rooms are just there for occasional use, like a guest room or a game room. So buying a purifier for a room you use occasionally isn’t necessary.

Rather focus on rooms that you spend the most amount of time in a day, like your bedroom. Also, there are rooms that are more susceptible to getting air pollution, like your kitchen, basement, etc. These rooms will definitely require purifiers.

  • Placement of Air Purifiers

The placement of the purifier in a room is vital in determining the number of purifiers required. If you can set up a purifier correctly, it can also effectively purify the atmosphere of the adjacent rooms.

Make sure to place your purifier where it faces no hardship when it’s sucking air in and filtering it out. Placing your purifier in a room where you spend the most amount of time while the purifier also cleans the adjacent rooms that you spend less time in is the best value you can get. So, plan accordingly.

  • Types of Pollutants

If you’re living beside a busy street or in a highly industrialized area, the air quality around you will be very poor. For such cases, the average measurement might not work for you.

Buy purifiers with a bit higher CADR rating than recommended if you find the air around you gravely polluted because you’ll need the extra power to eliminate all the extra contaminants.

Moreover, if you’re using HEPA filter purifiers, make sure you change the filter earlier than the recommended time.

Frequently Asked Questions

1. Is it better to have multiple air purifiers or one big one?

For larger rooms, you’ll need purifiers with a higher CADR rating. Well, you can get one large air purifier or two smaller ones. But, large or small, the total CADR value must add up to the recommended value.

Getting multiple air purifiers is more cost-effective than getting a large unit. It also offers a slightly more efficient purification. But the maintenance work will be much more for multiple units.    

2. Do air purifiers work for the whole house?

Yes, there are purifiers that can clean the air of your entire house. Unfortunately, such units are exceptionally large and expensive.

If your house is not that big, getting a standard PCO purifier and setting it up strategically should work fine for the entire house. For small homes with corridors, setting up the purifier somewhere suitable in the corridor should be adequate.

Final Words

If you don’t have proper placement planning and don’t get an adequate number of purifiers for your whole house, using a purifier would be nothing but a waste of money and resources.

So, based on the above-mentioned information, ask yourself how many air purifiers do I need to make the best out of the investment.

It’s better to get multiple purifiers for every room instead of a large central one. If the extra maintenance seems a hassle to you, you can get a central unit but make sure it covers the whole house. 

Last Updated on November 11, 2022

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Billy J. Weber

Hi. It’s Weber, founder and author of this site Currently you are reading. I am dedicated to provide valuable insights and practical tips to air enthusiasts and anyone interested in improving their indoor air quality.

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