To get rid of cockroaches in Malaysia permanently you need three things working together, not one product on its own: seal the entry points (drains, splashback voids, cable gaps behind appliances), kill the harbourage with professional-grade gel bait at hinges and behind the fridge, and stop using aerosol spray indoors. Done properly across three short visits inside a 14-day window, the harbourage is dead by day 14 and stays dead if the entry points stay sealed. Most Malaysian homes that keep buying Baygon every few weeks have done one of the three and skipped the other two. This is the full sequence in order.

Step 1 — Identify Which Lipas You Actually Have

Before anything else, work out which species you are dealing with. The two cockroaches that turn up in Malaysian homes need almost the opposite treatments, and the most common reason “permanent” treatments fail is that someone treated for the wrong one.

The German cockroach (Blattella germanica) is the small brown one — about 1.5 cm long, two dark stripes behind the head, lives indoors. If you are seeing them on the kitchen counter at night, behind the toaster, or scattering when you open a cabinet, that’s a German colony living in your kitchen. They breed indoors, the harbourage is inside your home, and one ootheca (egg case) carries up to 40 nymphs.

The American cockroach (Periplaneta americana) is the big reddish-brown one — about 4 cm long, flies clumsily at your face when you switch the porch light on. They live outdoors, usually in drains, gardens, and back-lane sewer systems. You don’t have an American colony in your kitchen. You have a corridor from the drain.

If you have both — and many Malaysian terrace houses do — you need to treat them differently. Indoor bait for German, drain and perimeter spray for American. More on telling the two apart in the kitchen.

Step 2 — Seal the Entry Points

This is the step most homeowners skip, and it’s the reason “permanent” never lasts. A perfectly baited kitchen with an open drain corridor to the back lane is not permanent — it’s a queue. New lipas walk in faster than the bait can kill the old ones. Before you place a single dot of gel, close the doors.

The entry points we find most often on Malaysian inspections, in rough order of frequency:

• Dry floor traps and sink U-bends. The water seal in your bathroom floor trap and under-sink U-bend is the only thing between your unit and the building’s waste riser. If nobody’s home for a week, the seal evaporates. Run water down every floor trap weekly. Pour in a cup of water before you travel.
• The silicone seal between splashback tile and counter. Cracks within 2 to 3 years. The void behind it is a German cockroach paradise. Re-silicone it.
• Cable and water-pipe gaps behind the fridge, oven, and washing machine. The conduit is always wider than the cable. Stuff with steel wool, then seal with silicone or expanding foam. Plastic-only seals get chewed through.
• Aircon condensate drain and AC pipe gland. Goes through the external wall into the splashback void or the bedroom. Almost never sealed properly by the installer.
• Cardboard from grocery deliveries. German cockroach egg cases hitchhike on cardboard from supermarket warehouses. The box doesn’t need to be from a “dirty” supplier — major Selangor supermarkets are the most common source we hear about. Unpack and bin the cardboard outside, not in the kitchen.
• The unsealed grease trap in landed houses. Usually accessible from outside, lid never properly seated, full of exactly what an American forager is looking for.

Twenty minutes of sealing with a tube of silicone and some steel wool does more for permanence than another RM50 of insecticide.

Step 3 — Remove the Competing Food

Gel bait works because the cockroach picks it over everything else available. If “everything else available” includes a film of grease on top of your cabinets, dog food left out overnight, and crumbs in the drawer seam, the bait dries out untouched and the colony continues.

This is not the auntie test about whether your house is clean. German cockroaches survive on milligrams of residue per day — they don’t need a feast. The places that matter are the ones nobody wipes:

• The top surface of your kitchen cabinets (the bit you can’t see from the floor). Grease drifts up and lands there.
• The drip tray under the dish rack. Empties slowly, never gets scrubbed.
• Pet food bowls left down overnight. Pick them up after 30 minutes.
• The rubber gasket around the oven door. Food residue collects in the fold.
• Behind the dish soap bottle, under the toaster, the crumb tray you forgot existed.

Three days of careful tidying before you bait does more for the outcome than another can of spray.

Step 4 — Switch From Spray to Gel Bait

Here is the unpleasant but useful bit of cockroach biology that makes permanent removal possible. They eat their dead. Nymphs especially, because they need protein. So one forager that eats a dot of gel bait, walks home, dies, and gets eaten by 30 of its harbourage-mates does the work of 30 sprays. Biologists call this horizontal transfer. It is the only mechanism that reliably collapses a German cockroach colony from the inside.

The actives in modern professional gel bait — fipronil, indoxacarb, hydramethylnon — are slow-acting on purpose. The forager has to make it home before it dies. A fast-acting spray kills the messenger and warns the rest of the colony to run.

How to place gel bait properly in a Malaysian kitchen:

1. Buy professional-grade gel, not aerosol. Maxforce FC Magnum, Advion Cockroach Gel Bait, or Goliath Gel — all available in larger Malaysian hardware shops and online. A small tube treats a whole flat and keeps for a year.
2. Pea-sized dots, not lines. One dot at each cabinet hinge (top and bottom — they harbour on hinges). One behind the fridge near the warm motor housing. One in the crack between stove and wall. One inside the cutlery drawer joint. 6 to 10 dots is enough for a typical kitchen.
3. Stop spraying. Pyrethroid spray near gel bait makes the bait smell wrong. The cockroaches won’t eat it. If you must spray for American cockroaches outside, restrict it to outdoor drains and the perimeter wall — never inside the kitchen.
4. Don’t wipe the dots. Mop the floor normally but leave the gel alone. It needs 2 to 3 weeks of working time.

The combination rule. Gel bait inside, at cabinet hinges and crevices. Non-repellent residual or pyrethroid spray outside, at drains and outdoor perimeter walls. Never swap the two around. Never spray over bait.

“I rented an apartment beside waste chamber, for 2 years being spraying consistently but to no avail. But this service clear the root problem by give bait to main points around the house so that even the little ones baited.”

— Afiq Zamanhuri (Google review, Nov 2024). Two years of spray, no result. One round of baiting at the right entry points, problem solved.

Step 5 — Three Visits in 14 Days, Not One

Most online guides quote 4 to 6 weeks between treatments to “match the egg cycle.” It’s a textbook answer that doesn’t survive a real Malaysian kitchen. Four weeks gives the surviving harbourage a month to find new food and rebuild. The faster cadence works better.

Three visits inside a 14-day window keeps fresh bait in front of the colony at every stage — adults dying, nymphs hatching, stressed survivors flushing into new corners. The colony never gets a quiet week:

1. Day 0 — initial bait placement at all known harbourages, perimeter treatment outside, entry-point seal-up.
2. Day 7 — refresh the dots (the first round has usually been eaten down), bait the second-tier harbourages that emerged as survivors flushed.
3. Day 14 — final flush, lift the fridge, pull the stove, torch the cabinet voids. Any nymphs from eggs hatched during the window now have fresh bait waiting.

By day 14 the harbourage is empty. This is the cadence Nomobug runs on the 3-visit 14-day plan — day 0, day 7, day 14 — and it’s the same logic you can apply to DIY if you commit to refreshing the dots properly on day 7 and day 14.

A recent job in Cheras — homeowner had been spraying Baygon every 2 weeks for over a year. Dead lipas every fortnight, never stopped. We pulled the stove out on inspection. About 80 German cockroaches in a 4-inch crack between the stove and the wall. Three gel dots inside the crack, two more at the cabinet hinges. By the second visit on day 7, no live adults found. Third visit was a formality.

— Job notes, Nomobug field team

Step 6 — Keep Them Out After the Kill

Permanent isn’t a one-time event — it’s the state you maintain after the harbourage is dead. The work that keeps the lipas out is small but it has to actually happen:

• Run water down every floor trap and U-bend weekly. Fill before you travel.
• Re-bait once every 3 months at the same hinge and behind-fridge points. A pea-sized dot is enough as preventive maintenance.
• Spray the outdoor perimeter — drains, back-lane wall, manhole covers — every 3 months with a residual pyrethroid. This is where pyrethroid spray actually earns its keep.
• Unpack supermarket cardboard outside, not in the kitchen. Bin the boxes the same day.
• Wipe the tops of cabinets and the oven gasket every 3 months. That’s the schedule, not “whenever you remember.”

What This Costs — DIY vs Professional

Honest market range for cockroach treatment in KL and Selangor in 2026: