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How Big Should a Powder Room Be?

How Big Should a Powder Room Be?

A powder room can be a great addition to your house. It offers convenience and comfort for your guests and enhances the privacy of your family. A powder room can also add to your home’s resale value and elevate its style quotient. 

If you are looking to build a powder room in your house, a question you may have struggled with is how big should a powder room be!

The International Residents Code (IRC) states that a powder room has a minimum size of 11 square feet. Although the average powder room tends to be closer to 20 square feet, the room needs to be adapted to work with the rest of the house’s layout.

With that in mind, here are all the factors you need to keep in mind when determining the size of the powder room!

Factor #1 – Existing Space

Many newly constructed homes have powder rooms built into the floor plan. However, adding a powder room to an existing home can have its challenges.

Hence, the most critical factor is looking at your house’s layout and finding the space to put in a powder room. 

You can decide how big your powder room can be based only on the existing space you have in the current floor plan of your home.

There are creative ways to add powder rooms in the smallest of spaces. You can also go all out and add a luxurious powder room. However, it all depends on how much space you have to spare.

Other than the amount of space, a crucial factor to consider is the location. Your powder room will require running water and drainage. Ideally, the powder room should be located close to the existing plumbing of your house to keep the costs down.

However, this may mean you have to make do with a smaller space for your powder room.

Factor #2 – Minimum Requirements

While you have full creative freedom to design the powder room of your dreams, there are a few minimum requirements you need to keep in mind.

These requirements are decided by the International Residential Code (IRC). This code is in use in 49 states and the district of Columbia.

The average size of a powder room is about 20 square feet. However, as per the IRC, you can have a powder room that is as small as 11 square feet.

Some of the other measurements that you have to be mindful of are:

  • There should be a distance of at least 15 inches between the nearest wall and the toilet centerline.
  • The powder room must have a headroom of at least 7 feet.
  • The clearance in front of the toilet should be at least 21 inches.
  • The width of the door must not be less than 32 inches.
  • The powder room needs to be ventilated by a window or a fan. 
  • The window should measure at least 3 square feet, and half of it must open to let fresh air in.
  • In the absence of a window, you must use a fan that provides ventilation of 50 cubic feet/minute.

I strongly recommended that you check these requirements with the IRC or your local building department before you start construction.

These regulations are revised regularly, so it is good to check for any new changes you may need to factor into your plans.

Factor #3 – Desired Features 

In addition to simply making it work inside of your home’s layout, the size of the powder room also depends on the features and fixtures that you want.

Here are some critical factors you need to consider before you finalize the size of the powder room:


There are no guidelines by the IRC on whether the door should swing in or out. So you are free to decide how you want it to be as long as you meet the minimum width requirements (minimum 32 inches).

If you want the door to swing inwards, the powder room will have to be slightly bigger to ensure it is easy to get in and out of.

If you are tight on space, you can go for doors that swing outwards or look at sliding doors.


Toilets come in a variety of sizes and styles. There are also different configurations, such as one-piece or two-piece. The toilet you choose will significantly impact the size of your powder room.

If you are keen on installing a two-piece toilet, the size of your powder room will increase. It is also important to remember that you need to follow the guidelines on minimum distances from the nearest wall, the sink, and the legroom.

Pro Tip: You can go for a smaller powder room if you choose a slimmer toilet that can be wall-mounted.


The sinks in powder rooms are for quick hand washing. It means that you can make do with sinks that are very small in size. Some sinks occupy as little as 12 inches of space and can be wall-mounted.

If you choose these smaller options, you can reduce the size of your powder room significantly.

However, if you’re someone who likes to have accessories on the sink, such as tissue holders and soap dispensers, you may need a larger sink with some counter space to hold these things.

Storage Cabinets

If you want the powder room to have a cabinet to store things such as towels and toilet paper rolls, you will need a bigger powder room.

These cabinets can be stacked against a wall or put under the sink. Some variants are small, light, and can be wall-mounted for space optimization. The typical depth of these cabinets varies from 16 inches to 24 inches. They can be as high as 36 inches. 

You will need to factor in these measurements before finalizing the size of your powder room. If you prefer to keep your powder room basic with no cabinets, you can keep the size compact.

Conclusion on Powder Room Size

A powder room can be a valuable upgrade for your house. It can be as small as 11 square feet.

However, how big a powder room should be will depend on factors such as the existing space in your floor plan, the location of your plumbing, and the features you want.

With careful planning and a dash of creativity, you can have a stellar powder room that is functional and doesn’t take up too much space!

Lindsay Reed

Hi, I'm the founder of! I created this website to be a resource for everyone who wants to make the best home possible.