How Do You Remodel a Shower?

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How Do You Remodel a Shower?

Recently, I was visiting a customer for a bathroom remodel in Irvine, California.  She asked me if there was more than one way to remodel a shower.  If yes, which is the best?

When considering how to remodel a shower, there are 5 primary methods:

  • Green board drywall.
  • Cement board.
  • Polyethylene.
  • Polystyrene.
  • Mortar.

A shower is fundamentally a mini swimming pool.  All tile and grout permeate moisture.  In other words, regardless of tile or grout quality or sealers used, all tile and grout will absorb moister.  This moister can, over time, penetrate beyond the tile and grout.  As long as the right installation methods are used, this does not cause a problem.  The most important part of any tile project is the preparation of the tiles sub-surface.  The sub-surface is what’s behind the tile keeping it strong, durable, and water resistant.  As with anything, the foundation is always the key to safety, quality, and durability.

Greenboard Drywall

How Do You Remodel a Shower?

This is perhaps the worse method of all.  Why?  Drywall (sheetrock) falls apart when it gets wet.  Installing a product like this when you remodel a shower is a bad idea.

Many years ago, this was a fairly common and acceptable practice.  Greenboard drywall was originally made for wet applications.  This included showers, bathtubs, steam rooms, etc.  It’s moisture and mold-resistant properties made it an ideal and super inexpensive product.  As time passed, it became apparent that, although well intentioned, was a bad idea.

These systems failed as they became wet.  As a result, homes were damaged due to moisture, mold, and rot.  This type of application is now illegal and not to code.

It really is a bad idea and can cause destructive damage to your home.  This system can also be extremely harmful to your health and safety.  It’s the least expensive way to tile a shower.  However, it’s also the worst.

Cement Boards

How Do You Remodel a Shower?

Cement boards are a combination of cement and reinforcing fibers.  These are formed into 3 by 5 feet sheets, 1⁄4 to 1⁄2 inch-thick that are typically used as a tile backing board. These boards can be nailed or screwed to wood or steel studs to create a substrate for vertical tile surfaces.

The most common are HardiBacker®, Durock®, and WonderBoard®.  Although preferred by many tile installers and contractors for its ease and speed of installation and lower cost, they will leak – I’ve seen it myself.  The problem?  Look at the picture.

What do you see?  You see lots of seams, nail, and screw penetrations.  Something you can’t see is that the walls are not plumb and square because these panels are installed directly over the wall studs.  When the tile and glass enclosure are installed, this becomes visible as the finished product has an “off” and unpolished appearance.

Polyethylene Sheets

How Do You Remodel a Shower?

Polyethylene is a waterproofing layer that protects moisture-sensitive substrates.  This type of system uses sheets of polyethylene.  The seams are covered using an unmodified thin-set mortar or other suitable trowel-applied waterproofing materials.  Common names are Schluter®-Kerdi Waterproofing Membrane and Schluter® Systems Kerdi.  This product comes in rolls and is applied directly over drywall or cement board.

Using thin-set mortar, tile can be applied directly over polyethylene.  Prior to installing the tile, all the seams receive a coating of thin-set mortar.  Shower drain and valve openings are covered using prefabricated polyethylene seals.  These too are applied using thin-set mortar.

This system is becoming increasingly popular with tile installers and contractors.  Why?  Like its cement board cousins, its ease and speed of installation and lower cost are great selling points.  What’s the reality?  Anything with a seam can fail.  Have you ever seen a swimming pool with a seam?

Polystyrene Foam Panels

Schluter®-KERDI-BOARD panels come in eight different thicknesses.  It is a multifunctional tile substrate and building panel.  These extruded polystyrene foam panels are designed to replace solid backing panels (i.e., gypsum board, cement backer board).  Can you imagine the weakness and reliability of 1/2-inch foam panel walls behind your tile?  How about the shower dam and pony walls?  These are prefabricated hollow sections of foam!  How strong and durable is this?

Using thin-set mortar, tile can be applied directly over these foam panels (they contain no cement).  Prior to installing the tile, all the panel seams, corners, and screw attachments are covered using 5-inch wide by 5mm (about 3/16 inch) thick strips of Polyethylene using thin-set mortar.

According to the manufacturer, these panels are “impact-resistant” and waterproof.  This system is also becoming increasingly popular with tile installers and contractors.  Why?  Like its cement board and polyethylene cousins, its ease and speed of installation and lower cost are great selling points.  What’s the reality?  Anything with a seam or hole can and will fail.  Returning to the pictures, look at all patched corners, seams, and holes.  Does this look like a secure, waterproof system to you?

Lath and Mortar

DAD's Construction Best Shower RemodelThis How Do You Remodel a Shower?process uses a water-resistant tile underlayment.  This consists of a vapor retarder, galvanized steel lath, and Portland cement mixture.  This system is an extremely effective moisture vapor retarder.  It is very strong, durable, and allows for plumb, square, and level walls.  This is the only system that was used for decades before other products promising similar results at less cost and faster installation were introduced.

There are no seams.  With a properly applied pan hot mopping application, creates the required “swimming pool”.  This keeps water from escaping into the homes wall and floor structures.  I’ve never seen a properly performed mortar system leak, crack, or deteriorate.  Mortar systems that were 50 plus years old still looked great.  They exhibited no water vapor damage or cracks in the tile.  It works – and it passes the test of time.

When Remodeling Your Shower, Don’t Make This Mistake.

How Do You Remodel a Shower?This is an example of a shower remodel using methods other than lath and mortar.  How long after the original remodel did this take?  It only took 5 years for this level of destruction.

You can easily see there was no hot mop.  It’s also evident that the shower pan and shower itself used a sheeting product.  Don’t believe hype and a low price!

The cost of the original shower remodel, repairing this damage, then doing the job right, far exceeded what it would have cost to do the shower correct the first time.  There was no savings whatsoever – only lots of extra cost.  The frustration of being without a shower (again) added to the client’s aggravation and anxiety.  Do it right the first time and save big!

How Can I Receive More Information On Remodeling My Shower Correctly?

If you would like more information on enjoying the best shower remodel experience, call DAD at (949) 380-0177 or at for a free in home consultation (DAD’s serves all of South Orange County California including Lake Forest, Mission Viejo, Foothill Ranch, Portola Hills, Ladera Ranch, Irvine, San Clemente, Dana Point, San Juan Capistrano, Rancho Santa Margarita, Coto de Caza, Dove Canyon, Laguna Niguel, Laguna Hills, Newport Beach, and Aliso Viejo).

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Daniel A. Derkum is the owner of DAD’s Construction, a leading South Orange County, California design-and-build remodeling and renovation contractor,  © DAD’s Home Services & Construction, Inc.  All Rights Reserved.