Before you begin shower drain pipe installation, there are a few things to consider. First, determine the existing drainage pipeline size.
What type of drain you install depends on whether you are replacing an existing wet-area drain or installing a new one. A wet-area drain requires larger pipes than shower drains do, since it must accommodate for sink installation.
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Installing the Drain Body
Installing a new shower drain to your bathroom is an essential DIY project if you want to enhance its aesthetic and functional qualities. There are various types of drains available, but you must choose which one best suits your requirements.
The drain body of a shower drain is the flange that sits atop the pipe under your shower. It usually includes a P-trap assembly to prevent sewer gases from entering your home through the drain line. A P-trap consists of two pieces: a coupler that fits two pipes together and an upright piece with 90 degree downward curve known as a trap weir.
To install a P-trap, first cut away the old shower drain pipe with either a hacksaw or plastic tubing cutter. This will leave a section of pipe that needs extending to accommodate your new P-trap.
Before you can remove the old drain, however, you must cut away its entire flange which is typically attached to the pipe. Doing this makes pushing out the old pipe much easier and allows you to access the drain body itself.
Once the drain pipe has been cut out, you can replace it with a new shower drain. There are two varieties of shower drains – solvent-glued and compression-style – so you’ll need to decide which works best for your requirements.
Solvent-glued shower drains are usually constructed out of PVC and come in a range of styles to match. They can be used with steel, fiberglass, and acrylic shower bases.
When installing a solvent-glued drain, be sure to follow the manufacturer’s instructions for installation. Furthermore, test-fit the pieces before adhering them together.
If you don’t have access from below your shower base, a special fitting tool can be used to install a compression-style drain. This type of drain is simpler to install than solvent-glued ones, though it may take more effort.
Once your drain body is installed, the next step is to lay a bottom mortar bed. This thin layer of mortar sits below the drain body and creates an angle away from walls toward the drain opening. Apply this mortar bed several inches below shower floor level as soon as possible after installing your shower drain.
Installing the Drain Pipe
If your home has a shower drain, it is essential to install the pipe correctly. Doing so will guarantee all water entering the shower drains properly and won’t cause any harm to walls or floor surfaces.
To begin installing a shower drain pipe, you must prepare the subfloor by taking out the old drain and P-trap and cleaning up any debris. After applying mortar around the opening of the drain, create an angle of 1/4-inch away from walls towards it; once dry, you can cover this area with waterproof membrane liner.
Another popular choice is a solvent-glued drain, which attaches the drain pipe to the shower floor with glue and silicone caulk. However, this type of drain requires access to the shower area such as from basement or crawlspace.
Solvent-glued drains come in a range of styles. Most feature a strainer, an upper drain body with female threads that screw into the lower body, and a smooth socket glued onto the pipe. You’ll also need fiber gaskets, rubber gaskets, and nuts for holding the body to its pipe.
Once all the pieces are collected, it’s time to put it all together. Make sure you have a pair of water pump pliers and the correct size wrench in order to unscrew the compression nut that secures your drain assembly to the waste pipe.
Depending on the type of shower drain you use, you may have to trim the pipe length to fit through an opening in the pan. This may require extra work on your part so be prepared for some extra effort.
If you’re unsure how to proceed, hiring a plumber might be your best bet. They have all of the necessary tools and expertise to guarantee your shower drain works as intended.
Installing the Drain Grates
Installing a shower requires proper installation of the drain grates. Failure to do so could cause water damage, rot and mold growth in your bathroom – rendering it unsanitary.
Shower drains come in a range of styles, such as linear grates and center drains. Both offer their own advantages; however, a linear drain has more placement options.
Linear drains can be installed on the floor, in the center of a shower, or across its entrance. Like traditional center drains, these can have metal covers that match or blend in with the tile work.
To prepare the area for drain installation, apply waterproofing onto the subfloor. This will protect it from absorbing any moisture from shower pan mortar mix. After the waterproofing has dried, you can install drain pipe.
Place the drain pipe in a smooth socket on the lower body of the drain, making sure there is an upward slope between its base and bottom. Apply plastic pipe primer along both outside edges of both pipe components before applying solvent glue on both surfaces. Gently slide in each pipe until secure; repeat for other holes as needed.
To prevent water from seeping under the grate, you should also lay down a layer of tar paper over the subfloor. With a utility knife, cut this layer so it covers all shower walls and corners.
Once this step is completed, you can begin the shower pan installation process. Be aware that this task requires a substantial amount of labor so be prepared to put in some extra hours working on it.
Once the shower pan is installed, you can begin tiling the rest of the shower. For best results, leave the top of the drain 1/16-inch below where tiles meet so that water drains away quickly and efficiently from your enclosure. This also helps ensure water doesn’t pool up on top as it runs downhill during heavy downpours.
Installing the Wet-Area Drain
A shower drain pipe is an essential component of the shower. It prevents water from pooling on the floor and creating a puddle, while also keeping moisture away from walls and floors.
If your drain pipe is leaky or damaged, replacing it is necessary. There are various methods for doing this but most often, using a special shower drain pipe works best.
Begin by taking out the shower pan. This will enable you to take out the drain strainer and compression nut that secures it to the drain body. To loosen this nut, wedge a flat-head screwdriver underneath it and pry it up.
Before diving in, it’s a wise idea to unplug any electrical outlets nearby. Additionally, using a drain snake can help break up clogs in the drainage pipe.
Once the nut is exposed, remove it by turning counterclockwise with a screwdriver. Alternatively, you can tap it with a hammer to loosen it further.
Next, cut a piece of drain pipe that extends from the top of the shower base up to approximately 3/4-1 inch below the lip of the drain (follow manufacturer’s instructions for proper height). Trimming is easiest with a hacksaw; however, if you don’t possess one, plastic tubing cutters can also be used instead.
Now, you must assemble and connect the new pipe to the existing drain pipe. To do this, you’ll need couplers and straight pipe. Additionally, you will require a P-trap assembly consisting of a coupler, 90 degree downward curve known as the trap weir and dip that shoots up into shower drain opening.
Finally, glue the P-trap assembly onto the new pipe. Be sure to rotate both components until they line up with a 90-degree elbow on your waste pipe.
Before attaching the P-trap and coupler pieces to the drain pipe, you may need to trim them slightly. This will enable the pipes to line up more closely with each other and create a tighter seal.