Did you know, more than half of homes in the United States have reported some problem with mold or mildew? Millions of people are highly susceptible to mold-related health issues. So, reducing excess moisture where mold spores thrive is one of the most important aspects of improving your indoor air quality.
Though mold and mildew can form anywhere excess moisture is present, bathrooms are one of the most common areas for mold growth to occur. One study of homeowners in the US found that mold was present in 49 percent of shower grouts and 50 percent of the shower walls. Finding ways to waterproof your shower's moist environment can undoubtedly help limit or even eliminate unwanted mold growth.
Below, Rise offers a complete guide on the shower waterproofing options that homeowners can use to enhance their healthy home. We will look at the best, low VOC options to ensure mold prevention in different types of showers.
Photo Credit: DGR Architecture + InteriorsWhat Shower Waterproofing Is Needed?
Most people assume that the tiles in your shower are 100 percent waterproof. Though ceramic and porcelain tiles on the floor and walls of your shower are virtually waterproof, the grout in between those tiles is not. Grout is nothing more than fine sand that is "glued" together with Portland cement and other types of adhesives. Grout does a great job at holding tiles in place. Still, it also readily absorbs water through the tiny capillary pores that are present throughout the mixture.
Without some sort of waterproof membrane beneath the layer of grout, those small masonry lines will gradually absorb water and cause water damage to whatever is underneath your shower. Plywood, drywall, and even the 2x4 studs of your wall or floor foundation are thus susceptible to wear and mold growth over time.
Below, we will talk about waterproofing methods for showers. Then we will look at the different types of membranes, coverings, coatings, or layers that can be used underneath the porcelain or ceramic tiles that make up your shower.
$269
Stiebel Eltron DHC-E 12 Classic Single or Multi-Point-of-Use Electric Tankless Water Heater - 203672
The Stiebel Eltron DHC-E 12 Classic Single or Multi-Point-of-Use Electric Tankless Water Heater - 203672 is a powerful, flexible, point-of-use water heating solution. The mighty DHC-E 12 offers high 12 kW output, in an affordable, compact package. Great for that kitchen sink at the end of a long pipe run, or for multiple low-flow sinks in a commercial application. 240/208V, 12 kW Copper Tankless electric with thermostat. DHC-E can deliver hot water to a single sink, multiple sinks, or in certain conditions, low-flow showerheads. You can control temperature simply by setting a dial. DHC-E models have the exclusive Electronic Temperature Control. This allows the temperature of the water to remain the same regardless of flow fluctuations. Features: Advanced microprocessor controls Best warranty in the industry Code compliance made easy No scalding Simple plumbing system design Sleek design fits in anywhere Seismic proof construction Proprietary technology Superior, reliable performance DHC-E models are suitable for booster applications, accepting a maximum incoming water temperature of 131 °F (55 °C).
$249
Stiebel Eltron DHC-E 8/10 Classic Single or Multi-Point-of-Use Electric Tankless Water Heater - 203671
Stiebel Eltron DHC-E 8/10 is actually two models in one - it has the added advantage of the selectable power output of 7.2 kW (Stage 1) or 9.6 kW (Stage 2) during installation via a jumper. 240V/208V - copper tankless electric with thermostat DHC-E can deliver hot water to a single sink, multiple sinks, or in certain conditions, low-flow showerheads. You can control temperature simply by setting a dial. DHC-E models have the exclusive Electronic Temperature Control. This allows the temperature of the water to remain the same regardless of flow fluctuations. Features: Advanced microprocessor controls Best warranty in the industry Code compliance made easy No scalding Simple plumbing system design Sleek design fits in anywhere Seismic proof construction Proprietary technology Superior, reliable performance DHC-E models are suitable for booster applications, accepting a maximum incoming water temperature of 131 °F (55 °C).
$42.69-$99.12
Niagara Conservation Earth Spa 3-Spray Handheld Showerhead (2 Pack)
All Niagara Conservation hand showers and showerheads come with a patented internal pressure compensator which enables a consistent output and flow of water regardless of available water pressure. Professionals and consumers prefer Niagara Conservation products because of their ability to conserve energy and water without sacrificing quality. Features: 2.0 GPM flow rate for efficiency without sacrificing performance 3-function showerhead provides a satisfying assortment of sprays to choose from 72 in. extra long stainless steel hand shower hose with anti-siphon valve is durable and flexible for ease of use Available in: Brushed Nickel or Chrome
$39.99
Brondell VivaSpring Filtered Showerhead in Chrome with Obsidian Face
Your Style. Filtered. You’re not just washing with H2O! Scary, right? Chlorine, lead, and mercury are all contaminants that can be found in your shower water. Protect yourself with the VivaSpring filtered showerhead, so you are not absorbing them through your skin or inhaling them through your shower steam. The VivaSpring showerhead uses patented technology to reduce these contaminants, and as a bonus, the process also has a mild anti-bacterial effect. This means you’re using safe, clean water when washing your most vulnerable and precious commodity – yourself! Certified filtration delivers smoother, younger-looking skin and silkier, shinier hair Wide soothing rain spray All metal connection for durability Metal ball joint for angle adjustment of the showerhead Easy clean silicone nozzles WaterSense certified Filtration tested & certified to NSF/ANSI standard 177
$124.19-$147.19
Evolve Technologies Tub Spout System With Shower Head
Featuring ShowerStart TSV technology, the ADTS delivers hot water up to 2X faster and provides more hot water for showering while saving up to 15 gallons per shower. Revive your bathroom with this forward-thinking tub spout and shower head combo to enjoy the definitive fusion of comfort, convenience, and conservation. Features Reduces wait times by delivering hot water up to 2X faster and automatically diverts hot water to the showerhead when it arrives. It helps your hot water last longer - saves gallons every shower. Enjoy the freedom to multitask instead of waiting, waiting, waiting for your hot water to arrive. The anti-leak design eliminates tub spout leaks while showering. High-pressure full body spray (single function version) or add massage and soap up pause with our multifunction version. Standard showerheads and handheld styles are available. This product can help a building earn Water Efficiency points in the LEED Green Building Rating System. Ideal for multifamily properties participating in Green Loan programs.
$149.99-$179.99
Nebia Corre Four-Function Handheld Shower Head, 1.5 gpm
There’s more to saving water than simply taking shorter showers. The Nebia Corre Four-Function Handshower features patented nozzle technology, resulting in 50% water savings as compared to standard 2.5 gpm showerhead sprayers without compromising water pressure or rinsing capability. That’s right—Corre’s nozzles are engineered to offer industry-leading water conservation while providing optimal spray velocity for absolute pampering, so you’ll never miss out on luxury. Toggle easily between the 4 different modes, from soft showerhead spray to high-pressure spray, and enjoy a shower that’s always tailored to your needs.Installation takes only a few minutes without fancy tools or plumbing experience. Simply remove your existing showerhead and hand-tighten the Nebia Corre Handshower dock onto your existing shower arm. Includes a 72 in / 183 cm hose and magnetic mounting for a secure hold and easy release. Prefer a fixed showerhead option? Up to 50% more efficient than a standard showerhead Engineered for optimal warmth, rinsing, and body coverage Toggle between 4 separate spray modes Designed for easy, DIY installation
$119.99-$149.99
Nebia Corre Four-Function Fixed Shower Head 1.5 gpm
There’s more to saving water than simply taking shorter showers. The Nebia Corre Four-Function Fixed Showerhead features patented nozzle technology, resulting in 50% water savings as compared to standard 2.5 gpm showerhead sprayers without compromising water pressure or rinsing capability. TCorre’s nozzles are engineered to offer industry-leading water conservation while providing optimal spray velocity for absolute pampering, so you’ll never miss out on luxury. Toggle easily between the 4 different modes, from soft showerhead spray to high-pressure spray, and enjoy a shower that’s always tailored to your needs.Installation takes only a few minutes without the need for fancy tools or plumbing experience. Simply remove your existing showerhead and hand-tighten the Nebia Corre Showerhead onto your existing shower arm. Up to 50% more efficient than a standard showerhead Engineered for optimal warmth, rinsing, and body coverage Toggle between 4 separate spray modes Designed for easy, DIY installation
$209.30-$272.30
PULSE ShowerSpas AquaPower Shower System - 1054
The PULSE AquaPower gives your bathroom a fresh and modern look by simply replacing your showerhead. The soft tips on the over-sized showerhead and handshower clear mineral buildup for long lasting performance and provide a soothing rain shower experience. You can enjoy a relaxing massage-like shower with the 5 PULSE AquaPower Sprays. The handshower’s 3 functions can be changed with a click of a button and the magnetic technology allows for easy return to the handshower holder. Easily switch between the showerhead, handshower and AquaPower sprays via the conveniently located diverter at the bottom of AquaPower. Features: Surface mounted and completely pre-plumbed, easily retrofit your existing shower without a remodel Oversized showerhead with soft tips to clear mineral buildup for long lasting performance Showerhead with air infusion technology Exclusive PULSE AquaPower Spray 3-function wand handshower Magnetic handshower and holder 180° horizontal pivoting shower arm
$112-$129.50
PULSE ShowerSpas PowerShot Shower System – 1056
The PULSE ShowerSpas PowerShot Shower System is the perfect showerhead and handshower combo to enhance your shower experience. The curved multi-function showerhead and it’s wide design provides a soothing rain shower, waterfall or PowerSpray. Conveniently switch to the multi-function handshower for those hard to reach areas or to assist you with household tasks such as cleaning your shower or showering your pet. The showerhead and handshower are designed to be used in tandem or independently. The PowerShot Shower System is designed be installed as a retro-fit and can also be used in a complete remodel. Mixing valve not included. Features: Surface mounted and completely pre-plumbed, easily retrofit your existing shower without a remodel 8” rain showerhead 3-function showerhead (waterfall, rain showerhead and PowerShot) 3 function handshower Unique and modern curved showerhead Conveniently located function selector Easily accessible diverter Drill-less installation
$465.35
Moen Velocity Brushed Gold Two-Function 8" Diameter Spray Head Rainshower
The rainshower experience that you can control is available in the Velocity showerhead with Immersion technology. A flip of a lever allows either a calming rain rinse function or a self-pressurized spray. Features: brushed gold pairs rich, warm tones with lush texturing for a timeless finish LifeShine® finish assures the ultimate in durability and is guaranteed not to tarnish, corrode or flake off generously sized 8" diameter rainshower for exceptional water coverage advanced, self-pressurizing Moen Immersion™ rainshower technology channels water through the showerhead with three times more spray power than most rainshowers for a more thorough rinse two-function full spray; concentrated rinse limited lifetime warranty
How To Tell If Your Shower Is Waterproof
So how exactly can you tell if your shower has sufficient waterproofing underneath the tile? Some tell-tale signs of a leaky shower include rotting floorboards, skirtings, door frames around the shower, water damage in floors and ceilings in adjacent rooms, dampness in carpets around the bathroom, the presence of cockroaches, silverfish, and other moisture-loving pests. However, before these severe issues occur, there are ways to detect a potentially leaky shower without ripping out tiles.
Some common indications that your shower is probably leaking water include:
- Visible holes or cracks in the grout between individual tiles on both the flooring and the walls;
- Cracking along the border and floor tile joints;
- No silicone used along the joints between tile floors and walls;
- Lack of silicone seals around the tapware studs of your shower;
- Incorrectly installed puddle flange connected to the drainage system of your shower.
Suppose you (or a hired plumber) detect any of these issues. In that case, it is highly likely that your shower is improperly waterproofed and may be leaking water.
What Is The Best System For Waterproofing A Shower Floor?
There are several different ways to waterproof the floor beneath your shower tiles. In the past, most contractors used a rubber or copper shower pan liner that was installed below a traditional mortar base. This system essentially allowed water to seep through the mortar joints slowly. The pan liner collected this excess moisture to protect the subfloor beneath. A potential risk of using this type of system is that shifting or settling of the shower can affect the liner's slope. This problem leads to the pooling of excess moisture, thus leading to the inevitable growth of mold.
Today, most contractors have ditched the rubber or copper pan liner in favor of some waterproof membrane technology. These different waterproof membranes are placed directly beneath the tile layer to avoid any water penetration into the cement or mortar subfloor. There are four main types of waterproofing membranes in use today including sheet membranes, liquid membranes, foam wallboards, and foam shower bases. We'll dive into them below.
Sheet Membranes
Sheet Membranes are manufactured from different blends of plastic compounds attached directly to the tile backer board and shower surface. Most sheet membranes have a "peel and stick" technology for easy installation.
RedGard. Photo Credit: Home DepotLiquid Membranes
This liquid membrane is essentially a waterproof paint for your shower. These products are applied with a simple paint roller. Once dried, the membrane becomes an elastomeric layer that stays flexible. RedGard offers one of the most popular and easy-to-apply products for a quick waterproofing of your shower.
Kerdi Board Shower Construction. Photo Credit: SchluterFoam Wallboards
Foam wallboards are installed as tile backers that offer structural stability. Because they are made from extruded polystyrene foam, they also provide a waterproof shower membrane. Kerdi Board is one of the most popular types of foam wallboards used for waterproofing showers.
Foam Shower Bases
Foam shower bases are often sold as kits that come with a foam shower curb that is waterproofed in the same way as the base. The equipment might also include a membrane bonding shower drain and seam tape. The foam used in these kits is often the same as the foam wall boards mentioned above.
The best system for waterproofing your shower floor will depend mainly on your budget and the remodel you are doing. If you are not entirely renovating your shower, liquid membranes are the easiest and quickest to install. If you are replacing a shower, opting for one of the other options will most likely add an extra defense layer against potential future water damage.
Photo Credit: Drip Drop WaterproofingIs Cement Board Necessary To Waterproof A Shower?
Cement board is a common backer used for showers and bathtubs. However, the cement board is water-resistant and not waterproof. This feature is an important distinction that should be taken into consideration. If minor leaks are quickly detected, the cement board should stay intact even though its core is not waterproof. However, extended leaks will often lead to permanent damage to the cement board. You should always use another type of waterproof membrane together with a cement board backing.
How Are Screw Holes Sealed In Shower Wall Waterproofing Membrane?
The waterproof membranes we reviewed above were mainly concerned with stopping water penetration through the tiles' grout lines. However, if you screw or drill holes into your wall or floor tiles, an extra coat of waterproofing will be required. The best way to waterproof screw holes is to correctly mark your holes, use the right size drill bit, and pre-fill the holes with silicone before installing the anchors. Once the anchors and screws are installed, add another coat of silicone around the screw hole. Check out this Rise guide for the best low-VOC adhesives and sealants for your home.
How Many Coats Of Waterproofing Should Be Applied In A Shower?
If you are using a liquid waterproofing membrane for your shower (most common for DIY projects), you should install at least two coats. Most liquid membranes will come with directions related to how long you need to wait between applying coats. In most cases, you should wait 24 hours before applying the second coat and then another 24 hours before using the shower. When properly applied, liquid waterproofing membranes for the shower should last at least ten years before needing a resealing.
Photo Credit: Borden InteriorsHow To Finish Waterproofing For Top Edge Of Shower
At the top edge of your shower, where the tile recedes to the wall, you should take extra care to add an extra layer of waterproofing. Drops and spray of water from your shower can accumulate at this critical point. If not properly sealed, moisture can penetrate underneath the tiles and cause damage to the cement board or other backing underneath the tiles. The easiest way to waterproof this top edge of the shower is with silicone caulking. If the gap is more than 1 cm thick, consider using a backer rod, a type of foam material used for this purpose.
Photo Credit: Construction 2 StyleHow To Install Waterproofing Membrane In Shower Walls
Liquid waterproof membranes can be applied to shower walls in the same way as to the flooring. You will want to go slow and apply a small amount to the paintbrush or paint roller you are using to make sure that it doesn't run down the wall. Alternatively, self-adhesive waterproofing sheets are another easy way to waterproof your shower walls. Sealing Solutions (SAM) offers unique, self-adhesive waterproofing sheets with a ten-year warranty on water tightness. You can apply these sheets to concrete, cement screeds, dry screed, existing ceramics (tiles), plasterboard, and even wood.
What Kind Of Tape Is Best For Cement Board Seams When Waterproofing a Shower?
Another critical element to waterproofing your shower is using the right type of waterproof seam tape at the connections between your backer boards. A simple, 2-inch alkali-resistant mesh tape should do the trick. You can also use a PVC self-adhesive caulking sealing tape.
What Type Of Shower Waterproofing Is Best?
The best type of waterproofing for your shower will depend on several different factors. In general, liquid waterproof membranes can be applied by homeowners for a simple, quick, and cost-effective way to waterproof your shower. If you are looking for a more robust and longer-term solution, opting for some sheet membrane or foam backer board is probably your best bet. For new shower construction, these more durable backer membranes are only nominally more expensive. You can combine them with liquid membranes for double the waterproofing effect.
Article By: Tobias Roberts
Tobias runs an agroecology farm and a natural building collective in the mountains of El Salvador. He specializes in earthen construction methods and uses permaculture design methods to integrate structures into the sustainability of the landscape.