Obs is a neighbourhood of narrow streets, terraced cottages and a Lower Main Road lined with restaurants and bars. Put two rivers, a hospital precinct and a lot of shared housing together and you get a steady diet of rat, cockroach and bed bug work.
The local picture in Observatory
German cockroaches spread through the party walls of terraced cottages, so one house treated alone rarely stays clear. Fishmoths and ants are common in the older homes.
Rows of little Victorian cottages share walls, roof spaces and sometimes back lanes, so pests move from house to house without ever going outside. Plenty have been split into digs for students and hospital staff. Restaurants and bars on Lower Main Road have cellars, back kitchens and bins in tight yards. Old suspended floors, cracked air bricks and lean-to kitchens added later are typical weak spots.
The Liesbeek and Black rivers meet on the eastern edge of the suburb, with the old River Club land and the observatory grounds alongside. Devil's Peak and Groote Schuur estate rise to the west. Winter rain runs down from the mountain toward the rivers, and the low-lying streets near the water stay damp.
Tell-tale signs
- Silvery, fast-moving insects are seen when you lift boxes, books or linen.
- Clothing, curtains or linen made from cotton, linen or silk have small holes or thinned patches.
- Wallpaper is lifting or damaged along the edges where the glue has been eaten.
- Fishmoths drop from the ceiling or come out of light fittings and cornices, a sign they are living in the roof space.
Fishmoths do not bite or spread disease, but they cause slow, steady damage. They eat the glue in book bindings and wallpaper, the starch in fabrics and paper, and the surface of photographs and documents. For offices, schools, libraries and archives, they can damage records that cannot be replaced. Their presence is also a strong clue to damp or poor ventilation that may be causing other problems in the building.
A note from the field
Fishmoths can live for several years and can survive months without food. That is why a single wipe-down does not work and why treatments that keep working in cracks are so useful.
When a technician deals with fishmoths, the first place they look is up. The roof space is often where the main population lives, out of sight, especially with the grey silverfish common in Cape Town.
What happens when we come out
Fishmoths often live in roof spaces, wall voids and behind cornices, so a fine insecticidal dust blown into the ceiling void is one of our most effective tools. Inside, we apply a targeted residual treatment into cracks, cupboard corners, skirting gaps and behind bookshelves rather than spraying open surfaces. Fishmoths are long-lived and lay eggs in hidden cracks, so treatments that keep working for a while are more useful than a quick knockdown. We pair the treatment with advice on damp, ventilation and storage, because changing the conditions is what stops them coming back.
Want the full step-by-step? See how our fishmoth control service works.
Stopping a repeat visit
- Seal cracks around skirting boards, cornices and built-in cupboards where they hide and lay eggs.
- Fix leaks under basins, around geysers and in the roof, since fishmoths need moisture.
- Vacuum regularly inside cupboards, along skirting boards and behind furniture to remove eggs and food sources.
- Avoid stacking old newspapers, magazines and cardboard boxes in cupboards for long periods.
- Improve ventilation in bathrooms and laundries with an extractor fan or by keeping a window open after showers.
Pricing, honestly
The price depends on the size of the property, how many rooms and cupboards are affected, and whether the roof space needs to be treated. Easy access to the ceiling void keeps the job simpler, while a home with lots of built-in cupboards and shelves takes more time. Offices, archives and storerooms with large amounts of paper are quoted separately, and every quote is free.
Fishmoths are active all year because they live indoors, but Cape Town's damp winters make them more noticeable as moisture rises in roofs, walls and cupboards. Grey silverfish in the roof space may become more visible in summer when the ceiling heats up and pushes them down into the rooms below.
Questions we get asked in Observatory
Why are fishmoths falling from my ceiling?
That usually means there is a population in the roof space. Treating the ceiling void with a dust is the most effective way to deal with it.
Are fishmoths and silverfish the same thing?
Yes. Fishmoth is the common South African name for silverfish, and it covers a few related species, including the grey silverfish common in Cape Town.
Do you come out to Observatory for fishmoth control?
Yes. Observatory is part of our regular Southern Suburbs route, along with Mowbray, Salt River, Woodstock, Pinelands. Most bookings are done within about 48 hours, and after-hours visits can be arranged.
Do fishmoths mean I have damp?
Often, yes. Common silverfish in particular need high humidity, so seeing them regularly in one room is a good reason to check for leaks or poor ventilation.
Do Observatory rats come from the Black River and Liesbeek?
A lot of them do. The banks give them burrowing ground and water, and the old drain network links the river to homes, so blocking air bricks and drain gaps matters here.
Can you treat a whole row of cottages in Obs at once?
Yes, and we recommend it when cockroaches or rats are moving through shared walls. Coordinated treatment stops them simply shifting next door.
Office 021 012 5825 · WhatsApp us
