A home can look clean and still be dirty. You may mop on Sundays, wipe the counters after dinner, and make the bed every morning, but none of that touches the inside of your aircon, the foam under your sofa cushions, or the rubber seal on your washing machine.
In a climate as warm and humid as ours, those hidden spots are where dust, mould, and dust mites settle in. Most of us only notice when something goes wrong. For example, when the aircon starts dripping, the laundry comes out of the wash smelling musty, or someone in the family wakes up sneezing every morning.
Some things you can definitely clean on your own in a matter of minutes, but there are others which you ought to get the pros to handle. Find out which is what, in our guide to things in your HDB flat or condo that are dirtier than they look, why they get that way, and how often you should actually be cleaning them.
1. Aircon
Image credit: Urban Company
The front panel of your aircon might look spotless, but in reality, the filter, coils, and blower wheel behind it are pulling in dust from your room the entire time you have it on. Throw in the condensation which an aircon produces in our humidity, and the inside of the unit becomes a damp, dark spot where dust and mould can build up.
You’ll usually notice one of three signs first: A musty smell when the aircon is switched on, weaker cooling even at the lowest temperature, or water dripping from the unit. That last one often means the drain pipe or tray is clogged.
Image credit: Urban Company
General servicing means opening up the unit and flushing the drainage, so it’s a job for a technician to handle. That’s where Urban Company (iOS | Android) comes in clutch with their certified aircon specialists and signature FoamJet servicing. It uses foam and high-pressure water jets to deep-clean the front and back of the evaporator coils and the blower wheel, lifting out the dirt that regular cleaning leaves behind. If you’re a new customer, get their aircon services from $20/unit with the code <TSLFOAMJET>.
How often to clean it
- Filters: Rinse every 2 weeks if you use the aircon daily. This takes 10 minutes and you can do it yourself.
- General servicing: Every 3 months for daily use.
- Chemical wash or overhaul: Every 1 to 2 years for heavily used units, or sooner if cooling stays weak after a general service.
2. Mattress
Image credit: Urban Company
Whenever you change the bedsheets, your bed feels clean, but the mattress beneath is soaking up sweat and collecting the skin cells you shed, which is exactly what dust mites feed on. A study by NUS and Dyson, covering 27 Singapore homes, found the highest concentration of dust mites in mattresses, along with mould, bacteria, and allergens.
This matters more here than in most places. In a study of around 8,000 people by A*STAR and NUS, about 80% of Singaporeans have allergic reactions to house dust mites, and roughly 40% had allergic rhinitis. If you wake up with a blocked nose that clears by lunchtime, your mattress could be part of the reason.
A vacuum lifts surface dust, but it won’t reach mites and allergens deeper in the foam. Urban Company’s sofa and mattress deep cleaning is a 6-step process: dry vacuum, foam shampoo, scrub, wet extraction, spot treatment if necessary, and drying, which gets a visible result in one visit, with prices from $49.
How often to clean it
- Washing: Wash your bedsheets and pillowcases weekly in hot water if the fabric allows.
- Vacuuming: Once a month, with the upholstery attachment.
- Deep cleaning: Every 6 months, or every 3 months if someone in the household has allergies or asthma.
3. Fabric sofa
Image credit: Urban Company
The sofa is where we snack during Netflix and chill sessions, nap after work, and let the kids, and in some cases, pets, climb all over. Fabric upholstery traps all of it: crumbs, spilt drinks, pet hair, and the same skin cells and sweat that mattresses absorb. Like your mattress, the soft padding gives dust mites a warm place to live.
The giveaway is usually the armrests and the seat you always sit on. If they’re a shade darker than the rest of the sofa, that’s a sure sign of body oil and grime that’s settled into the fibres.
Deep cleaning a sofa at home is risky. Use too much water, and the foam will stay damp, which is how a sofa starts smelling musty. Urban Company covers sofas under the same deep cleaning service as mattresses, at prices from $49, so it makes sense to book both in one visit.
How often to clean it
- Vacuuming: Weekly, including under the seat cushions, where crumbs collect.
- Spot cleaning: As soon as something spills, before it soaks into the foam.
- Deep cleaning: Every 6 to 12 months, or every 6 months if you have pets and young children.
4. Washing machine
Image credit: Modori
The washing machine is one of the appliances we assume cleans itself, since it’s full of soap and water everyday. But water and leftover detergent can pool in the rubber door seal and the detergent drawer, and they rarely dry out properly, especially in laundry areas or service yards with little airflow.
Researchers at Germany’s Furtwangen University found 229 types of bacteria across 13 home washing machines, and the bacteria behind that familiar musty laundry smell turned up in 9 of the 13 door seals. If your freshly washed towels smell a bit off, the machine is the likely culprit, not your detergent.
You don’t need the pros to clean this for you. Invest in a washing machine cleaner and follow the instructions, or use the preset drum-clean setting if you have one. If your machine still smells after a couple of rounds, it’s worth getting a technician to check the filter and drain pump.
How often to clean it
- Door seal: Wipe it dry after your last load of the day, and leave the door ajar so the drum can air out. If your machine is in a poorly ventilated room, consider blowing a fan at it to help the drying along.
- Detergent drawer: Pull it out and scrub it once a month.
- Drum clean: Run an empty hot cycle with a washing machine cleaner once a month.
5. Kitchen hood & grease filter
Image credit: FUJIOH
If your household cooks regularly, your cooker hood is catching a lot of oil every week. Most of it ends up in the metal grease filter and trap underneath. Once the filter is clogged, the hood can’t pull smoke out properly, so the grease settles on your cabinets and backsplash instead.
In time, grease build-up blocks airflow and makes the fan work harder, and this can become a fire risk if the motor overheats.
Cleaning the trap and filter is a quick DIY job, and many metal filters can go in the dishwasher, though you should check your appliance manual for washing instructions. If you’ve got a part-time cleaning service, such as Urban Company’s professional cleaners, get them to handle cleaning of the hood exterior, backsplash, and cabinet tops during their weekly cleaning sessions.
Urban Company’s part-time home cleaning sends the same professional every session if you book weekly or fortnightly, so you’re not briefing a new stranger on where your floor trap is every time. They arrive fully equipped, and the price is fixed before you book, from $39 for 2 hours.
Use the code <THESMARTLOCAL> for $20 off weekly or fortnightly sessions.
How often to clean it
- Metal grease filter: Soak in hot soapy water once a month, or once every 1 to 2 months if you cook less often.
- Charcoal filter: Replace every 3 to 4 months.
- Hood exterior: Wipe down weekly before the grease turns sticky.
6. Bathroom grout, floor trap & shower head
Image credit: Urban Company
Bathrooms can stay wet for hours after every shower, and in our climate it can be hard for them to dry out completely. That’s why the grout lines between tiles slowly turn grey or black, and why the corners near the floor are often the first place mould shows up.
Two spots get missed the most. One is the floor trap, which collects hair and soap scum until water starts pooling around your feet when you shower. The shower head is the second, where a slimy film called biofilm builds up inside. A University of Colorado Boulder study of shower heads from 656 homes in the US and Europe found that biofilm often contains mycobacteria. Most of those microbes are harmless, so there’s no need to panic, but it’s a good reason to give the shower head a soak now and then.
Newly launched on the Urban Company app is their Bathroom Deep Clean service (from $65), which utilises pro-grade chemicals and equipment targeted at build-ups, stains, limescale, mould, and grout. Think: descaling pins to clear blocked shower heads, high-temp steam cleaners with detail attachments, and eco-safe disinfectant on high-touch zones.
In other words, this is for the grime that a regular clean can’t fix.
How often to clean it
- Floor trap: Clear out hair weekly.
- Tiles and grout: Scrub weekly, and use a mould remover on the grout once a month.
- Shower head: Soak in vinegar every 3 months to clear limescale and film.
7. Window tracks & grilles
Image credit: Window Grill Singapore
Run a finger along your sliding window track and it might come back black. That’s a mix of dust, traffic grime and rainwater that’s settled into the groove, and it builds up fastest if you live near a main road or an expressway, or have ongoing construction nearby. Window grilles collect the same dust on every bar, which then blows straight into your home when you open the windows.
There’s also a safety concern when it comes to keeping the tracks clear. Sliding windows that can’t move smoothly along their tracks are one of the causes the Singapore Building & Construction Authority (BCA) has flagged in cases of fallen windows, and homeowners can be fined up to $10,000 if a window falls from their unit due to poor maintenance.
Wiping tracks and grilles is easy to add to a regular cleaner’s list, so you don’t have to necessarily do it yourself. Window repairs, on the other hand, will need the services of a BCA-approved window contractor.
How often to clean it
- Window tracks: Vacuum and wipe monthly. Use an old toothbrush to get into the corners.
- Grilles and panes: Wipe down monthly, or every 2 weeks if you live near a main road.
- Safety check: Every 6 months, which is what BCA and HDB recommend. For casement windows, check that the rivets aren’t corroded and the screws aren’t loose. For sliding windows, check that the safety stoppers and angle strips are in place.
8. Fridge door seal
Image credit: Fridge Seal
The next time you open your fridge, gently pull back the rubber seal around the door. The folds are where drips of sauce, milk, and condensation collect, and because the seal is cold and slightly damp, it’s a common spot for black mould to grow without anyone noticing.
A dirty seal is also a leaky one. Grime and stiffness stop the door from closing tightly, so cold air escapes and the compressor runs harder than it needs to.
How often to clean it
- Door seal: Wipe the folds with warm soapy water once a month, and dry them properly.
- Shelves and drawers: Clear out and wipe down every 3 months, ideally when the fridge is emptiest.
- Quick seal test: Close the door on a sheet of paper. If it slides out easily, the seal needs cleaning or replacing.
This is a 15-minute DIY job. If the seal is cracked or still won’t close properly after cleaning, contact your fridge service centre for a maintenance or replacement check.
The TL;DR cleaning schedule you need
| How often | What to clean |
| Daily | DIY:
|
| Weekly | DIY:
Professional:
|
| Every 2 weeks | DIY:
|
| Monthly | DIY:
Professional:
|
| Every 3 months | DIY:
Professional:
|
| Every 6 months | DIY:
Professional:
|
| Every 6 to 12 months | Professional:
|
| Every 1 to 2 years | Professional:
|
One company to clean the whole house
Image credit: Urban Company
It’s terribly troublesome to look up a cleaner for each of the household items we’ve mentioned on this list. That’s multiple vendors, quotations, and inquiries you have to look through, just to find the best of each.
If that sounds unappealing to you, Urban Company is your one-stop shop covering everything from aircon servicing and repairs, to sofa and mattress deep cleaning, as well as post-reno cleaning and home repairs. And it all sits in one nifty app to sort you all out.
All of their professional cleaners are background-checked, trained, and reviewed, with backups on standby for when your cleaner cannot make it. You won’t be blindsided by hidden costs, and you don’t have to worry about providing any cleaning supplies either.
If you’re looking for routine cleaning, you can even request the same cleaner, so you don’t have to deal with a new stranger in your home each time. Best of all, it takes a mere few taps on your phone for instant confirmation.
The next time you’re looking to outsource your cleaning and repair jobs, check out Urban Company, and don’t forget to use <THESMARTLOCAL> for $20 off weekly or fortnightly cleaning, and <TSLFOAMJET> for aircon servicing from $20/unit for new customers.
Book your Urban Company cleaning service here
This post was brought to you by Urban Company.
Cover image adapted from: Urban Company, Lazada
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