May 15, 2022
This guide provides clear, step-by-step instructions for installing a HydroBlok™ Shower Niche within your shower system. It covers everything from preparing the wall and marking the niche location to sealing, fastening, and finishing. Following these steps ensures a precise, watertight installation that integrates seamlessly with HydroBlok™ wallboard panels. Whether you’re a professional installer or a DIY homeowner, this guide will help you achieve a clean, durable, and waterproof result.
HydroBlok™ Shower Niche Installation Guide
Before Installing Your HydroBlok™ Shower System
Perform a final floor and wall measurement check to ensure all walls are square.
Make any required adjustments before installing your HydroBlok™ shower system.
Installation Tools & Materials Required
#2 Robertson or #2 Phillips screwdriver drill bit
Tape measure
Fine-point marker
Level
Utility knife with metal ruler or straight edge
Cleaning supplies (paper towels, citrus wipes, rags, dustpan, brush)
Important:
Read all related installation guides before beginning. Contact your local dealer if you have any questions about the installation process.
Installation Steps
Step 1: Decide the Size and Placement
Confirm that your HydroBlok™ wallboard is properly installed and ready for the shower niche.
Determine the desired size and location of the niche within your shower wall.
Step 2: Frame the Shower Niche
Locate and mark your wall studs.
The niche must be positioned so that there is a stud on each vertical side to provide full support.
Step 3: Mark Placement on the Wall
Hold the niche in position with its face against the wall.
Use a level to ensure it’s straight, then trace the outline of the niche onto the wallboard using a fine-point marker.
Step 4: Cut the Opening
Horizontal Lines First
Using a utility knife, cut the horizontal lines first.
These guide cuts help ensure the vertical cuts land in the middle of a wall stud on each side.
Step 5: Confirm Stud Location
Double-check that both vertical cuts align with the wall studs before completing the vertical cuts.
Step 6: Dry-Fit the Niche
Insert the niche into the opening to ensure it fits properly.
Make any necessary adjustments before applying sealant.
Step 7: Apply Joint Sealant
Run a ½” continuous bead of HydroBlok™ Joint Sealant along all four inner edges of the wallboard opening.
Step 8: Press-Fit the Niche
Press the niche—right side up—firmly into the opening.
Smooth out any excess sealant using a HYDROBLOK standard putty knife.
Step 9: Install Washers & Screws
Secure the niche with HydroBlok™ washers and screws:
Fastener Placement
Place fasteners at each corner and along both vertical seams every 12".
Each washer should overlap half on the niche and half on the wallboard.
For Double-Wide Niches
Install additional washers and screws at the top and bottom of the center stud and along the horizontal seam.
Step 10: Apply Final Joint Sealant
Apply a final ½” continuous bead of HYDROBLOK Joint Sealant along all four seams.
Smooth it with a straight putty knife to fully cover all washers.
Ensure there is at least 1" of sealant coverage on each side of every seam.
Step 11: Apply Thinset
After approximately one hour (at a room temperature of 18°C / 65°F or higher), the HydroBlok™ Joint Sealant will skin over, and thinset can safely be applied.
