Shower Remodeling

A shower is a small waterproof box built inside a house that is otherwise designed to stay dry. Everything about building one well comes down to that: keeping water inside a defined assembly and getting it to a drain.

Most of the shower work we do in Essex and Union County is replacing a shower that failed. Usually it failed because the waterproofing was never really there.

Why showers fail

Grout is porous. Water passes through it in normal use, which is expected and fine, because the layer behind the tile is supposed to catch it. When that layer is missing, wrong, or badly detailed at the corners, the water reaches the substrate, then the framing, then the ceiling below.

The specific failures we find most often:

• No waterproof membrane at all. Tile set directly on cement board, which is a stable substrate but not a barrier.
• A failed liner or pan. Old lead or PVC liners crack, and the pre-slope beneath them was frequently omitted, so water sits rather than draining.
• Tile over drywall or greenboard. Common in work from the 1970s onward. Greenboard is moisture-resistant paper-faced drywall and it turns to mush in a shower.
• Bad corner detailing. Membranes fail at changes of plane, at the curb and at the drain connection, because those are the hard parts.
• Rigid grout in movement joints where flexible sealant belongs, which cracks and then admits water.

What a rebuild involves

Demolition down to the studs and subfloor in the wet area. That is when we find out how far the damage travelled: soft sheathing, rotted plates, wet insulation, damaged joists. In an older house it is normal to find some of this and it is better to price the repair honestly than to build a new shower over compromised framing.

Then plumbing. If the valve is old, this is the moment to replace it with a pressure-balancing or thermostatic mixing valve, which is required in showers and prevents the scald when a toilet flushes elsewhere. If the supply lines are galvanized steel and closing up internally, this is the only convenient opportunity to replace them.

Then the assembly: pan, waterproofing, backer, tile.

Shower pans

The floor of a shower has to slope to the drain at roughly a quarter inch per foot, and it has to be waterproof. Two approaches are standard now.

A mortar bed with a membrane is the traditional method done properly: a sloped pre-slope layer, a waterproof liner over it connected to a clamping drain, then a second mortar layer on top to receive tile. It is labor-intensive and it works. The critical detail is the pre-slope, because without it water that reaches the liner sits there permanently.

A pre-sloped foam pan paired with a bonded sheet or liquid membrane is the more common modern approach. The pan comes with the slope built in, the membrane bonds directly to it and up the walls, and the drain is a bonding-flange type designed for the system. Installed to the manufacturer's specification it is reliable and faster.

Either works. What does not work is mixing components from different systems, which voids the manufacturer's warranty and, more to the point, tends to fail at the transitions.

Waterproofing the walls

Cement backer board is a substrate. It does not rot and it holds tile, but water passes straight through it. It needs waterproofing either behind it as a vapor barrier or, more commonly now, over it as a bonded membrane.

Sheet membranes are bonded to the backer with thinset and taped at the seams and corners. Liquid-applied membranes are rolled or troweled on in multiple coats to a specified thickness, with reinforcing fabric at the corners. Both are proven. Both depend entirely on the corners, the curb, the niche and the drain connection being detailed correctly, because that is where every failure starts.

Drains, valves and controls

A standard center drain is the simplest and works with any pan. A linear drain sits along one edge, allows the floor to slope in a single direction, and permits larger-format tile on the shower floor because it only needs one plane of slope. Linear drains are what make many curbless showers practical.

On controls, a single-handle pressure-balancing valve is the standard requirement. A thermostatic valve holds a set temperature and allows multiple outlets: a shower head plus a hand shower on a diverter, for instance. If you want two outlets running at once, the supply piping and the valve have to be sized for it, which is a decision made at rough-in.

A hand shower on a slide bar is worth adding on almost any project. It makes cleaning the shower far easier, it helps with washing children or pets, and it is the single most useful accessibility feature you can install without changing the room.

Niches, benches and glass

A niche gets framed between studs, which means its position is constrained by where the studs are and by whether the wall contains plumbing. The sill should be sloped slightly so water drains out rather than pooling. Waterproofing a niche is fiddly and it is exactly where a rushed job leaks.

A bench can be a full built-in, a floating bench cantilevered off the wall, or a fold-down seat. Built-in benches need the top sloped very slightly toward the drain and need waterproofing carried over the whole assembly. They also eat floor space, so in a small shower a floating bench or a fold-down seat is usually better.

Glass is measured after the tile is finished, because it is cut to the actual opening. Frameless panels look best and cost most; semi-frameless is a reasonable middle. A fixed panel with no door, a walk-in screen, avoids the swing clearance problem entirely in a small room, at the cost of a little more spray.

Tile choices for showers

Wall tile can be almost anything rated for wet areas. Floor tile has to be safe underfoot when wet, which means texture or a small tile format where the grout lines themselves provide grip. A polished large-format tile that looks beautiful on the wall can be genuinely dangerous on a shower floor.

Small mosaics on the floor follow a sloped plane easily, which is why they are traditional in a shower with a center drain. Large-format floor tile needs a single plane of slope, hence the linear drain. More detail on the bathroom tile page.

What drives shower cost

• Size and tile coverage, including whether you tile to the ceiling.
• Hidden damage found at demolition, the genuine unknown in every shower job.
• Pan type and whether the entry is curbed, low-curb or curbless.
• Plumbing changes, including a relocated drain or replacing old supply piping.
• Valve selection. A thermostatic valve with multiple outlets costs more than a single pressure-balancing valve.
• Niches, benches and shelves, each of which adds waterproofing detail.
• Glass. Frameless is a significant line item on its own.
• Tile format and pattern, since small mosaics and complex patterns are far more labor.

Related work

If the tub is coming out anyway, look at a tub-to-shower conversion. If you are keeping a tub, see bathtub replacement. If the whole room is dated, a full remodel is often better value than doing it in pieces.

Shower work across our service area

We rebuild showers in Irvington, Maplewood, Union, Bloomfield and across our full service area. Back to bathroom remodeling.

Every town has its own bathroom remodeling page covering the housing there and what it means for a project. See the full service area.