The Danger of Drilling Blindly
Hit a concealed PVC water pipe and you get an instant flood through the wall and floor; hit an electrical conduit and you risk a hard power trip, a damaged bit, and a real fire and shock hazard. Both turn a 10-minute DIY job into a repair bill many times the cost of doing it right the first time.
How to Locate Hidden Pipes
In HDB bathrooms and kitchens, water pipes usually run vertically directly from the ceiling to the sink or shower mixer. Never drill directly above or below a water outlet!
Use a Stud & Wire Detector
Invest in a reliable wall scanner that detects live AC wires and metal pipes. Always scan the intended drilling spot in an X-pattern before making the first hole.
Not sure if it's safe to drill? WhatsApp us for a quick checkKnow Your HDB Wall Before You Drill
Not every HDB wall behaves the same way, and that changes how deep you can safely go. Internal partition walls in most flats are lightweight blockwork or dry partition (gypsum on a metal frame), while the structural shear walls and the wet-area walls in bathrooms and kitchen yards are dense reinforced concrete. The riskiest spots are the wet-area walls: behind the tiles run concealed PVC cold/hot supply pipes and, in older flats, embedded conduit feeding the water heater and bathroom point. As a rule, treat any tiled wall within 300 mm of a tap, mixer, water heater, switch or power point as a no-drill danger zone unless you have scanned it thoroughly.
Conduits in HDB flats almost always run vertically or horizontally in straight lines from a switch, socket or DB box, never diagonally. So if you can see an outlet, mentally extend a straight line up, down and sideways from it and avoid drilling along that path. The same logic applies to a water tap or heater — the feed pipe runs straight to it.
How Deep Is Safe? A Quick Diagnosis
Most TV brackets and shelves only need 40–50 mm of bite into the wall. Concealed services usually sit 15–30 mm below the plaster or tile bed, which is exactly why shallow holes are safer. Set a depth stop (or wrap masking tape around the drill bit) so you never plunge deeper than the anchor needs. Drill on the rotary setting only — switch the hammer action off near suspected services, because hammer mode is what punches clean through a PVC pipe before you feel any resistance.
Danger Zones & Safer Alternatives
| Location in flat | What's likely hidden | Safer approach |
|---|---|---|
| Above/below a switch or socket | Live electrical conduit | Shift 200 mm to the side of the outlet |
| Bathroom / kitchen tiled wall | PVC water supply pipe | Drill into the tile grout line, scan first |
| Near the water heater | Hot/cold pipes + heater wiring | Avoid the whole panel; call a pro |
| Living/bedroom partition wall | Usually clear; light fixture wiring up high | Lowest risk — scan, then drill shallow |
When to DIY vs Call a Handyman
Reasonable DIY: a single shelf bracket or a picture hook on a dry living-room or bedroom partition wall, where there's no outlet or tap nearby and you've scanned the spot in an X-pattern. Call a pro if any of these apply: you're mounting a heavy TV (a dropped 55-inch set is far more expensive than a callout), the wall is in a wet area, you found a positive reading on your scanner, you're unsure whether the wall is structural, or you don't own a verified live-wire detector. A trained handyman carries a proper multi-scanner, knows typical HDB conduit routing, mounts to the right anchor for your wall type, and absorbs the liability if something goes wrong — and you get a written quote before any drilling starts.
Indicative FixMove handyman rates: a standard drilling and mounting job is typically from S$80, a TV bracket mount from around S$90–S$150 depending on size and wall type, with the final figure confirmed on site after the technician assesses the wall. If you do strike a pipe, a plumber callout to fix a burst concealed line starts from around S$120 and can climb fast once tiles have to come off — which is exactly why scanning beforehand pays for itself.
For full job-by-job ranges, see our handyman cost guide and book a mounting job through the FixMove handyman service. If you suspect concealed wiring near your drill spot, our electrician cost guide and plumbing service page cover what a recovery job actually involves.