Cockroaches are the single most common pest complaint we get across Mumbai, Navi Mumbai and Thane. Two species dominate: the small German cockroach that lives inside kitchen cabinets, appliance motors and hinge gaps, and the larger American cockroach that travels up from drains, chutes and basement pipe shafts.
The distinction matters, because the treatment is completely different. German cockroaches are an indoor breeding problem and need bait. American cockroaches are an entry problem and need drain treatment plus proofing. Spraying the floor helps neither.
Step 1: Work out which cockroach you have
If the roaches are 10–15 mm long, light brown, with two dark stripes behind the head, and you mostly see them near the stove, sink or fridge motor, they are German cockroaches. If they are 30–40 mm, reddish brown, and you see them at night near drains, bathrooms or the utility area, they are American cockroaches.
A mixed infestation is common in older buildings, and it needs both approaches in the same visit.
Step 2: Remove the three things that keep them alive
- Water: fix dripping taps, dry the sink at night and wipe under the fridge and water purifier. Cockroaches survive weeks without food but only days without water.
- Food film: grease behind the stove and under the platform is a food source. Degrease those surfaces, not just the visible countertop.
- Harbourage: cardboard cartons, old newspaper stacks and unused appliance boxes are prime nesting material. Clear them out before any treatment.
Step 3: Use gel bait, not spray, in the kitchen
Odourless gel bait is applied as small dots inside hinge gaps, drawer runners, appliance motor housings and cable entry points. Cockroaches feed on it, return to the harbourage and the active ingredient passes through the colony including nymphs you never see.
Spraying the same area actually works against you: it repels the cockroaches deeper into voids, scatters the colony to neighbouring rooms and contaminates the bait so they stop feeding on it. If you have sprayed recently, tell your technician — bait placement has to shift to untreated surfaces.
Step 4: Treat drains and shared shafts
American cockroaches enter through floor traps, the kitchen chute and pipe shafts shared with neighbouring flats. Treating only your flat means reinfestation within weeks in a building where the shaft is untreated.
Fit drain covers on unused floor traps, seal the gap around the pipe where it passes through the wall, and raise a common-area treatment with your society committee. Society-wide shaft treatment is where most permanent results come from in Mumbai high-rises.
Step 5: Expect the timeline
Gel bait does not kill on contact. You will typically see dead cockroaches from day 2, a visible drop by day 7, and near-total control by days 14–21. Seeing a few roaches in the first week is normal and is actually a sign the bait is drawing them out.
If activity is unchanged after three weeks, the likely cause is missed harbourage — usually the fridge motor, the chimney duct or a neighbouring flat feeding the population back in.
When to call a professional
Call for a treatment if you see cockroaches in daylight (a sign of overcrowding), if egg cases keep appearing after cleaning, if there is a smear or musty odour in cabinets, or if a shop-bought treatment has already failed once. RPS cockroach gel baiting for a 1 BHK starts around ₹1,199 and carries a 90-day warranty.
Need this handled professionally?
RPS Pest Control has served Mumbai, Navi Mumbai and Thane for over 15 years with CIB-approved treatments, same-day service and written warranties.