Attic Bathrooms - Can They Work?

Believe it or not, you can fit a full bathroom including a tub, vanity, and toilet in pretty much any attic. Homebuilders don’t usually make attics with bathrooms in mind, however, which means you’ll have to alter this space considerably to set up your ideal attic bathroom. Learn all about the special considerations you’ll need to make as you build an attic bathroom and the steps you’ll take to make your remodeling dreams come true.

Special Considerations for Attic Bathrooms

Adding an attic to your bathroom is much more complicated than building a bathroom in any other part of your house. Here are some of the considerations you’ll need to keep in mind as you embark on this project:

Location

If your attic is anything like the norm, its roof slopes down on two, three, or even all four sides. With this type of layout, finding the right spot for your new bathroom can be hard.

While it would be ideal to put your bathroom in the center of your attic, this approach would limit the accessibility of the remaining space in this part of your home. Bathrooms on the edges of your attic can have windows, but in this type of attic bathroom, the roof might slope all the way down to the floor.

Permits

Depending on where you live, your local building codes might require you to get a permit to build a bathroom in your attic. Instead of assuming there aren’t any relevant codes, check in with your local planning office to make sure you’re in compliance.

Structural Support

There’s probably no greater home renovation nightmare than building a brand-new attic bathroom only to have your tub crash through the floor the first time you fill it up. Most attic floors aren’t designed to bear considerable weight on a regular basis, which means you’ll need to add structural support to the floor in your new bathroom to avoid disasters.

You can use a joist span table to determine how much added support you’ll need in your new bathroom. Keep in mind that live weight is very different from dead weight; when you expect to have a lot of foot traffic in your attic, you’ll need to support your floors accordingly.

How to Build an Attic Bathroom

Here are all the steps you’ll need to follow to install a stylish and comfortable bathroom in your attic:

1. Collect Your Tools

You’ll need quite a few different tools and supplies to pull off your new attic bathroom project:

• ½-inch or ¾-inch plywood for subflooring
• 2x4s for flooring support and walls
• Floor covering
• Drywall sheets
• Drywall screws
• 14-gauge and 12-gauge electrical wiring
• GFCI outlets
• Plumbing supply lines and drainage lines
• Toilet
• Bathroom vanity
• Bathroom sink
• Shower
• Bathtub

2. Create a Floorplan

Before you proceed with building your new bathroom, you’ll need to design a floorplan. If you want to go all-out, you can use a 3D design suite like AutoCAD, but there are also plenty of handy mobile apps you can use to make great floorplans.

First, you’ll need to determine exactly how much space you’ll allot for your new bathroom and decide how long each wall will be. Next, determine where each bathroom feature will be based on size. Your tub will be the largest feature in your bathroom closely followed by your vanity.

If your original calculations don’t afford enough room for each of your bathroom features, you can revise the overall dimensions of your bathroom. Keep in mind that you can save space with bathroom feature options like pedestal sinks and wall-mounted toilets.

3. Construct the Subfloor and Walls

Now that you know exactly where everything will go in your attic bathroom, it’s time to start making your new room into a reality. After you’ve strengthened the joists in your bathroom area, lay down full sheets of plywood to construct the subfloor. Depending on the size and shape of your new bathroom, you may need to cut multiple plywood sheets to fit snugly against your new walls.

Next, frame the interior, non-load-bearing walls with 2x4s. After you’ve mounted your drywall sheets on both the interior and exterior walls, you’ll have a bonafide room. Just don’t forget the door.

4. Set up the Electricity

You’ll need to run at least two 20-amp circuits into your new bathroom. Plus, you’ll need an overhead light, and you’ll probably want to install a fan even if it isn’t required in your local building codes. If you don’t install a fan in your new bathroom, you’ll have to install a window that can open, which can be tricky in a sloped space like an attic.

5. Install the Plumbing

While setting up supply and drainage lines in an attic bathroom is relatively easy, venting can pose a vexing problem to many DIY-friendly homeowners who want to take care of their attic plumbing themselves. If you don’t vent your attic plumbing lines effectively, you could experience drainage issues throughout your house, so you should probably hire a professional plumber to lend you a hand for this step.

6. Install Your Flooring

The flooring in your attic bathroom should be relatively light to avoid adding any unnecessary loads. While this consideration means that solid marble tiles are probably off-limits, you can still install some attractive vinyl flooring or even set up some lightweight hardwood floors that will make your new space extra comfortable.

7. Install Your Features

Now that your new attic bathroom has walls, plumbing, and electricity, the only step left is to populate your grooming space with bathroom features. Take care of the hardest part first; begin by taking your tub up the stairs and finagling it into position. Next, install your vanity and sink, and if you plan to have a separate shower, install it right after the toilet.