A leaky shower drain can wreak havoc on the framing underneath. If you have a plastic shower base, you can replace the drain from inside the shower.
Introduction
I got a call to look at a problematic leak in a neighboring house some time ago. The drywall in the ceiling was bulging and there was a steady drip coming down from the bulge, indicating that water was pooling on the other side. A catastrophe was just waiting to happen; the drywall wouldn't last much longer.
The leak was directly underneath the upstairs bathroom, which had a pre-fab vinyl shower. It quickly became clear the shower was the culprit because the dripping intensified whenever anyone used it. I had to replace the ceiling drywall anyway. I could have gotten access to the shower drain plumbing, but it turned out I didn't need to.
A closer inspection revealed that the leak was caused by water seeping past the outside perimeter of the shower drain cover. The good news was that it's easy to fix that from inside the shower. The problem stemmed from the fact that the shower pan wasn't properly supported — probably because the installers forgot to lay a mortar bed — and it flexed whenever anyone stood on it. Eventually, the seal around the drain cover broke, and water began to seep around the drain perimeter.
Replacing the Shower Drain Without Access Below It
It took a specialty drain cover to complete this repair. Other manufacturers may supply them, but the one I used was from WingTie. It has a rubber O-ring that seals around a 2-inch drain pipe (adapters are available for 1 1/2- and 2-inch copper pipe) and four screw anchors that fix it to the shower floor. This is pretty much the only type of drain cover you can install without going underneath the shower.
What's a Compression-Style Shower Drain?
A compression-style shower drain cover seals onto the shower pan via compression (not glue). Most have a threaded flange onto which you screw a large nut from underneath the shower base. Instead of threads and a nut, the WingTie drain cover has anchors that you can tighten from above.
When to Call a Plumber
If your shower isn't leaking from the drain cover, but from somewhere else, you might need a plumber's help. The drain pipes could be leaking, or water could be spraying from one of the supply lines. You'll probably also need a plumber if you have a tile or stone shower and the drain is leaking, because WingTies aren't designed for anything other than plastic or fiberglass shower bases.
Tools Required
- Flat-head screwdriver
- Phillips screwdriver
- Putty knife
- Rags and/or paper towels
- Rotary tool with saw or grinder attachment
- Tape measure
Materials Required
- Silicone caulk
- Soap and water
- Top-mount shower drain
Project step-by-step (5)
Step 1
Remove the old drain flange
Use a flat-head screwdriver to pry off the drain strainer. You may have to remove a screw before it will come off. The section to which the strainer attaches is called the drain flange, and you must remove it before installing a new drain cover.
Step 2
Clean up the drain opening
Scrape old plumber’s putty or silicone caulk away from the drain opening, using a screwdriver or a putty knife. When you’ve removed all the residue, wash the area around the drain thoroughly with soap and water and let it dry.
Step 3
Prepare the new drain
The new drain comes fitted with a rubber gasket that fits snugly around the waste pipe. Turn it over and apply a bead of silicone caulk to the underside of the flange. Push the four anchors flush against the side of the drain, so they don’t get in the way as you place the drain onto the waste pipe.
- Pro tip: You can use plumber’s putty instead of silicone caulk. It doesn’t seal quite as well, but it does make the drain easier to remove if you have problems in the future.
Step 4
Install the drain
Insert the tapered end of the drain into the drain opening, fit it around the waste pipe and push down to seat the flange onto the bottom of the shower pan. Keep pushing down to keep the flange as close to the shower pan as possible while you tighten the four anchor screws in turn, using a Phillips screwdriver.
As you tighten the screws, the anchors will draw the drain snugly against the shower base, and caulk will begin to ooze out. Tighten each screw until a uniform amount of caulk oozes from the drain perimeter and the screws are hard to turn, then clean off the excess caulk with paper towels or with a rag.
After you’ve cleaned off all the caulk (I usually wipe many times to be sure it’s all gone), snap the strainer onto the drain. You can turn on the water immediately, even before the caulk has set, to ensure no water seeps through around the drain perimeter. If you see seepage, remove the strainer and tighten the screws a little more.
Step 5
FAQs
How much does it cost to replace a shower drain?
A drain you can install from the top of the shower base costs about $40, and a tube of silicone caulk costs less than $10. If you do the installation yourself, your cost will be less than $50, but if you hire a plumber, the cost may be from $150 to $300, depending on the labor rate.
What are the different types of shower drains?
Shower drains come in four styles: round, square, linear and tie-in. Linear drains have a narrow, rectangular shape, and tie-in drains, which are designed to be covered by the same material as the shower floor, can be square or rectangular. Both have to be built in when you’re constructing the shower base.
Most pre-fab shower bases have a round depression around the drain hole and will only accept a round drain, although some have square depressions for a square drain.
Are shower drains a universal size?
Most shower drains have a standard 2-inch outlet to fit a 2-inch drain pipe. The size of the actual drain opening can vary depending on whether it’s a linear, tie-in, round or square drain.
What’s the best way to unclog a shower drain?
Soap and hair are the main causes of shower drain clogs, and the best way to remove them is to remove the strainer and fish it out with a cable-tie drain cleaner. An enzymatic drain cleaner can dissolve what you can’t reach. Pour in the recommended amount, wait several hours, pour in some more, and then wait overnight and flush the drain with hot water.
Originally Published: November 18, 2019
