Skip to main content
Stesso
Project

Install Waterproofing Corners — Waterproof Seams with Banding

Beginner8 hours

Part of project

How to Install a Waterproof Foam Shower Niche · Step 6 of 6

Helpful?

In this video

Apply thin-set mortar to all inside and outside corners where the walls meet the pan and curb. Embed the pre-formed waterproofing corner pieces into the mortar. Use a flat trowel or putty knife to press the corners firmly, ensuring there are no air bubbles. Clean excess mortar with a damp sponge.

Goal: Waterproof critical junctions

  • Installing corners before the main wall membrane simplifies the process and ensures a fully sealed layer underneath the main sheets.

Used in this video

  • Putty Knife (Tool Type: Hand Tools) — Smoothing and embedding the corner pieces into mortar.
  • Grout Sponge (Tool Type: Cleaning Tools) — Cleaning up excess thin-set mortar.
158.3K views65630 minutes
Home Repair Tutor

671K subscribers

View Channel

FAQs

The project is listed as 'beginner' difficulty, but 8 hours seems like a long time. What makes this project take so long, and is it truly suitable for a first-timer?

While the individual steps are straightforward, the 8-hour estimate accounts for careful measuring, precise framing, allowing sealant to cure, and meticulous waterproofing. Rushing these critical steps can lead to leaks, so taking your time to ensure everything is perfect makes it beginner-friendly by emphasizing accuracy over speed.

The required tools list several different drills. Do I need multiple drill/drivers, or will one standard cordless drill suffice for this project?

You only need one capable cordless drill/driver, such as the RYOBI ONE+ 18V Cordless 1/2 in. Drill/Driver, to complete this project. The multiple listings provide options for suitable tools. Ensure your chosen drill has enough power to drive screws into wood studs and backer board efficiently.

What is the most critical step to ensure the shower niche is completely waterproof and won't leak?

The most critical step is the meticulous waterproofing of all seams, especially where the niche meets the backer board. Apply a continuous bead of high-quality waterproof sealant like DAP Ultra Clear, and then properly embed waterproofing banding over all seams and fasteners. This creates a monolithic, leak-proof barrier essential for preventing water damage.

What if my existing wall studs aren't perfectly spaced for the pre-fabricated niche? Do I need to modify the framing?

Yes, you will likely need to modify your wall framing using 2x4 lumber to create a precise, sturdy opening for the niche. This often involves cutting existing studs and installing horizontal blocking to perfectly frame the niche's dimensions, ensuring a flush and stable installation. Accurate framing is crucial for long-term stability and waterproofing.

Transcript
Hide

then you clamp it in with this clamping ring and then you're good to go. No need to do any bonding flanges. Next we're going to install all of our inside and outside corners. I know typically people do corners last but you have to bear with me because I think you're going to like this method and that's why it's a little bit different.

Auto-generated transcript. May contain errors.