Floor Drains & Open Showers in a Bali Villa

Most villas in Sanur have an open or semi-open shower where water runs straight onto the tile and into a single floor drain. That setup is lovely in the dry season but puts real strain on the trap, the slope, and the pipe below during months of heavy rain. A few simple habits will keep it flowing and stop insects from working their way up into your bathroom.

Open-Air Showers: What Makes Them Different

In Sanur you will rarely find a fully enclosed Western-style shower cubicle. The typical layout is a raised wet area with a glass panel on one side (if any) and a large open face looking out over the garden or pool. All that water has exactly one exit: the floor drain set into the tile.

Because the shower is exposed, sea-salt air settles on every surface. Over time that salt, combined with PDAM tap water or well water that can be quite hard, leaves a mineral film inside the drain channel and around the trap seal. Add soap scum and hair, and the passage narrows month by month.

The Floor Drain and Its Trap

A proper floor drain in a Bali villa usually has two parts: a removable grate (the 'trap cover') you lift off to reach the channel below, and a P-trap or U-bend further down the pipe that holds a small amount of water to block sewer gas from rising into the room.

Lift the grate once a week during the rainy season and pull out the hair-and-grit plug that forms at the bottom. Rinse it under a hose. If the channel itself looks coated in white scale, soak a cloth in white vinegar, lay it over the opening for twenty minutes, then scrub with an old toothbrush. Avoid pouring chemical drain cleaners down a septic-tank system; they kill the bacteria your tank depends on.

If water still sits in the shower area after you turn the tap off, the problem is likely below the grate—either a partial blockage in the first metre of pipe or a collapsed trap seal. That is when a plumber's camera inspection saves you from digging up tile.

• Lift and clean the grate weekly in the wet months, bi-weekly in the dry season.
• Never mix chemical drain opener with any other product; if you smell gas or see unusual bubbling, stop and call a professional.
• Keep a spare grate and rubber gasket in your utility cupboard—salt air corrodes them faster than you expect.

Slope: The Detail Most Renovations Get Wrong

Water only moves toward the drain if the tile surface actually falls that way. In older Sanur villas built before 2010, the slope was sometimes poured at 1–2 % instead of the recommended 3–4 %, or it dips slightly away from the drain because the original screed settled unevenly over the years.

To check, pour a thin sheet of water across the shower floor (a garden hose on low works). Watch where it pools for ten seconds. If a puddle forms more than 15 cm from the drain and does not flow toward it, the slope is insufficient.

A small dip can be corrected by re-grouting the affected tiles with a self-levelling compound to add a few millimetres of fall. A major issue means lifting the wet-area tiles and re-pouring the screed—a job best left to a builder who has done Bali villa bathrooms before, because the waterproof membrane underneath must stay intact.

Keeping Insects Out of Your Drain

Bali's humidity means any standing water in a trap becomes mosquito breeding ground within two days. Cockroaches and small ants also travel up through open drains, especially after heavy rain when their outdoor burrows flood.

The simplest fix is to make sure the P-trap always holds its water seal. If you have not used the shower for several weeks (say, during a trip back home), run the tap for thirty seconds before leaving so the trap refills. A dry trap is an open highway.

Fit a fine stainless-steel mesh screen over the grate opening—cheap at any hardware shop in Sanur. It stops leaves, sand from the beach, and larger insects while letting water pass freely. Replace it if it starts to rust; salt air will eat thin wire quickly.

• Run water through the drain every 5–7 days if the shower sits unused.
• Add a mesh screen over the grate to block debris and crawling insects.
• During the rainy season (November–March), check the trap weekly for stagnant water and algae.

A Simple Maintenance Rhythm

You do not need a complicated schedule. Think of three moments: weekly, seasonal, and 'something looks wrong.'

Weekly: lift the grate, pull out hair and grit, rinse the channel. Two minutes with a bucket and a brush.

Before the rainy season (around October): give the whole drain line a good flush with hot water, inspect the gasket under the grate, replace the mesh screen if corroded, and confirm the P-trap holds water.

After an especially heavy downpour: walk past the shower area and look for damp patches on the tile or a musty smell at floor level. If you notice either, clean the trap immediately—standing water in a poorly sloped area is where mould starts in a tropical climate.

'Something looks wrong': slow drainage, gurgling from the toilet when you shower, or a persistent foul smell despite a full trap means there may be a partial blockage further along the pipe or a cracked connection to your septic tank. Send a photo of the grate and the surrounding tile to a local plumber for a quick assessment before it becomes a flooded bathroom.

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