This project started as a challenge to fix a three decade old custom shower with some cool Miami Vice features like a glass block wall and wall-mounted water jets. It turned into a masterclass for how to renovate shower waterproofing. The shower showed signs of leaking. The demo revealed why.
But first, the before. This shower was pretty 1970s groovy but also had some not so cool ‘features’ like grungy and uneven floor tile.
Click on this “How to Renovate a Tile Shower” link if you’d like to skip ahead to the tile install and final result pics. But for details on how to renovate shower waterproofing, keep reading!
The Diagnosis
These folks in Austin, TX, had persistent mildew on the outside of the brick exterior wall where the showerhead was located. There were no symptoms of a sudden water pipe leak. If a pipe in the wall had suddenly developed even a small drip-leak, the gallon or more of water per day put into the wall would have melted the entire adjacent interior drywall. This was a shower waterproofing problem putting an ounce or so of moisture into the wall every time the shower was used.
This shower was more than 30 years old. And the clients were not the first owners, so they had no idea what kind of waterproofing it had. The clients had bought the house just a few years prior, and suspected it had been flipped just before they bought it.
These were all clear signs that they needed to renovate the shower waterproofing by going down to the studs. Ripping everything out and starting over would reveal any homeflipping shennanigans. The trick on this project would be figuring out how to preserve the cool 1980s -style glass block wall. This would save $2,500 or more in replacement glass cost.
The Plan
The clients needed to completely renovate the shower waterproofing, which meant going to the studs and concrete slab slubfloor. But they wanted to maximize their renovation budget. So here was the creative cost savings plan to make a large spa shower renovation:
- Demo the original shower to the studs BUT preserve the original glass block wall and alcove entryway
- Repair any water damage to the wall framing
- Create a large vertical niche space
- Install new shower fixture plumbing and a Kerdi drain system
- Install concrete backerboard for the walls and a custom-sloped deck mud shower floor
- Waterproof the shower walls with RedGard and the shower floor “pan” and glass wall base with Kerdi
- Install new wall tile, floor tile, and grout for a fabu new shower experience!
Did it all go according to this plan? Read on if you’re curious about how to renovate shower waterproofing. Or, skip ahead to this “How to Renovate a Tile Shower” post if you’re just wanting to know how it all turned out!
STEP ONE: Demo
Taking a leaky shower down to the studs is the only sure way (short of x-ray vision) to know what’s going on underneath the tile. This demo quickly revealed the problem. The shower “pan” waterproofing was a thick custom installed fiberglass liner. This is great for traditional shower waterproofing, especially for a shower originally installed in the late 1980s.
What wasn’t so great was the complete lack of any preslope for the fiberglass pan. You need to slope the waterproofing towards the drain! The moisture absorbed by the concrete layer underneath the shower floor tile instead flowed away from the drain. So, water pooled all around the preimeter of the shower base.
The whole perimeter of the shower floor was still a moist mildewy mess even though the clients hadn’t used the shower for a whole month before demo. The lack of a shower pan preslope also really exacerbated this major problem:
There used to be a shower bench in that corner properly wrapped in fiberglass to integrate it into the rest of the shower waterproofing. But during the home flip just before the home was sold to my clients two years previous, the shower had been ‘updated’ to eliminate this bench. Whomever did the ‘remodeling’ simply sawed through the fiberglass waterproofing and then just patched the surface tile to blend.
The surface finish work was done so well that even I hadn’t spotted it initially. What wasn’t done well? Not fixing the bigass hole left in the shower waterproofing.
Tile and grout are not waterproof. Sawing through the fiberglass shower pan put moisture directly into the wall every time the shower was used. The skillful visible work blending the patch tile with the original wall and floor tile hid a super shoddy leaky shower dryrot mess underneath:
STEPS TWO and THREE: Reframe and Re-Plumb!
Renovating a leaky shower always requires framing carpentry repair. The dry-rotted exterior wall sill plate needed to be replaced. But carpentry work gives an opportunity to completely renovate your shower and make a spa.
These folks decided to re-frame an interior wall for a new super-tall tiled niche. They also chose to reframe and replumb with fancy German fixtures for a true spa shower experience. Their new shower would have three stacked inset body sprays and a control manifold to send water in three different directions:
The basic piping was pretty simple, but the fixtures themselves were very exacting to install. The in-wall body spray nozzles and housings required really tight tolerances for a flush and level finish with the wall tile.
STEP FOUR: Drain Plumbing and Floor Slope
Installing the drain-side plumbing was easy in comparison. After verifying that the original conventional shower drain was in good shape, I simply used a Kerdi adapter kit to convert the drain to a Keri-compatible system. Here are pictures of the step-by-step conversion process:
Getting the shower floor slope right took a bit more work. The shower had a very large 4×9 footprint, and the glass block wall made a U-turn into the shower to form a kind of entryway vestibule. So I had to install, pack, and slope the shower floor slope concrete in sections.
The good thing about drypack concrete is it’s very forgiving. If you have the patience to pack and shape a sandcastle, then making a properly sloped shower floor only requires a little bit of added math and some cut to length guides.
STEP FIVE: Backerboard and Waterproofing
The clients chose to use concrete backerboard with RedGard paint-on waterproofing for the shower walls and Kerdi waterproofing fabric for the shower floor and curb. Waterproofing the masonry base of the glass block walls required a creative combo of both materials (along with a generous helping of Sika masonry sealant):
Maybe not pretty, but definitely effective! Kerdi for a shower base and RedGard on concrete backerboard for shower walls creates a completely waterproof shower install that will last a lifetime. It’s the equivalent of a metal roof for your house. If done right, you’ll never have to think about it again.
This shower is now ready for tile. To see how the rest of this tile shower renovation went (and to see pics of the final result), just click on this “How to Renovate a Tile Shower” link!