A frameless shower is designed to have small gaps in the seams of the glass panels and around the door. Gaps exist because the unit lacks the thick metal frames found on traditional framed shower products. The custom nature of a frameless shower also lends itself to less lenient tolerances than prefabricated framed units. Although a frameless shower should never be considered a completely airtight enclosure, there are some techniques that can be followed to minimize the amount of moisture coming out of the shower.
One technique to minimize the amount of water that leaks through the seams of a frameless unit is to use polycarbonate inserts that create seals between the panels or between the glass and the surrounding walls of the enclosure.
A standard single door (less than 30″ wide and 78″ high) has a 3/16″ gap between the wall and the door glass where the door hinges to the wall. On the handle side of the a gap of 3/16″ from the door. A gap between the door and the wall is recommended for the door to swing properly. Finally, a 7/16″ gap is left between the sill and the bottom of the door glass.
To prevent water from seeping under the door, a polycarbonate sweep is attached to the bottom of the glass. The sweep directs water into the shower and acts as a weatherstrip under the door.
There are gaps on both sides of the door. However, unless the shower head is pointed directly into the gaps, an extremely minimal amount of water, if any, will escape. The potential for minimal leakage is the tradeoff between heavy glass frameless showers and less custom thin glass framed units.
When your shower configuration includes a door and panel, there is an open space between the door and the panel. This space can be virtually eliminated through the use of a strike. When the door is closed, it rests against the lock that is attached to the panel, sealing the gap.
There are a multitude of other polycarbonate parts that can be used in certain situations to seal gaps. Consult your local glass company for non-standard needs.
In addition to using polycarbonate seals, building your opening so that the walls are plumb, level, and square helps ensure that all the pieces of the enclosure fit together better.
A third extremely critical technique to prevent water leaks is to eliminate any flat surfaces in the shower where water can collect. This is done by creating slopes with the tile so that the water returns to the shower.
There are two areas where the tile should be installed with a 5 degree slope. The first area is the seat (if applicable) that the return panel glass sits on. The return panel is usually where the shower head is pointing directly. If your enclosure has a seat, water will naturally collect as it splashes onto the return panel. If your mosaic job is done correctly, you shouldn’t have any major problems. However, poor tile work can easily be taken advantage of if water sits and sees through the grout joints. To prevent water from pooling on the seat, make sure the seat plate is gently tilted back in the shower at about 5 degrees.
The second area that water can exploit if not built correctly is the sill or curb. The sill is usually a single piece of marble that runs along the bottom of the shower opening. It is usually located a few inches from the floor and is the threshold you cross every time you get in and out of the shower.
When the water hits the door or in-line panel, it rolls down the glass. The door sweep has a sloped end that directs water away from the door. Rolling off the sweep end, the water hits the sill. A properly constructed shower door sill will have a slope of about 5 degrees so that water will roll off the door, off the sweep flap, down the sill and back into the shower.
If the sill is not sloped, the water will pool and the pressure of moisture falling above will slowly force it to find an exit around the door. Even the smallest spaces in the enclosure are large enough for water to flow out and into the surrounding bathroom. The amount of water that escapes from use may not be very noticeable. However, over time, the continual presence of water outside the shower can cause noticeable damage to wood and other surfaces.
You must be especially careful with fiberglass shower trays. While it’s okay to install a frameless shower door in a tiled opening that uses a fiberglass pan as a base, the online specifications for these products don’t mention whether the sill is sloped. If it’s not sloped, water has the potential to pool and increase your frameless shower leaks.