Having your windows cleaned: how often, safety at height and what the window cleaner does

Clean windows may seem like a detail, but they largely determine how light and well kept a home feels. Anyone who has ever cleaned the windows of a second floor from a ladder also knows that it is not a job you quickly do in between other things. This article explains how often windows need cleaning and why that differs per home, what a professional window cleaner does and which methods they use, what a clean includes, which safety rules apply to working at height, and who arranges and pays for the outside of the windows if you live in an apartment or a rented home.

How often should you have the windows cleaned?

There is no fixed rule. Many window cleaners work with a regular round and come by once every few weeks to once a quarter; how often it is really necessary depends mainly on the surroundings. Glass manufacturers advise cleaning facade glazing at least once every six months in any case. A more frequent rhythm makes sense if the windows get dirty quickly or if you value clear glass, for example with large glass doors on the garden side. A less frequent rhythm can work for a home in a quiet, green area with an overhang that protects the windows from the rain.

Besides the glass itself, the frames also need attention. Dirt and algae on the paintwork hold moisture, and regular cleaning helps the paintwork last longer. So if you have the windows cleaned, it is best to have the frames done at the same time. How to make the paintwork itself last as long as possible is explained in Exterior painting: when to paint and what the painter does.

Why windows get dirty: traffic, sea, trees and new builds

The speed at which windows get dirty depends mainly on the surroundings:

• Traffic and railways. On a busy road, a grey film of soot and fine dust settles on the glass. Along the railway, fine metal particles from brakes and overhead lines can also end up on the glass; these are often difficult to remove with water alone.
• Sea and wind. On the coast, the wind carries salt with it. After drying, a dull salt deposit remains that comes back quickly, especially after stormy weather.
• Trees and gardens. Pollen, aphids and honeydew from trees leave a sticky layer, and bird droppings and cobwebs do the rest.
• Rain and weather. Rain does not rinse the glass clean. Raindrops pick up dust from the air and leave spots after drying; this is most obvious on the side facing the weather.
• New builds and renovations. After construction, there are often residues of cement, lime, sealant, paint or plaster on the glass. This construction dirt calls for a separate post-construction clean. Scraping dry glass with a blade or scraper can cause scratches, especially if there are grains of sand in between; glass manufacturers warn that scraping with a blade always carries a risk of scratching, especially with coated glass, and that damage to toughened glass can be particularly noticeable. Have this done by a window cleaner with experience in post-construction cleaning, or ask the contractor whether it is included in the handover.

Lime deposits from new brickwork or concrete can also run onto the glass and frames when it rains, especially in the first period after construction. Residues of cement, mortar and concrete are highly alkaline and can etch the glass surface if they are not rinsed off quickly.

What a window cleaner does: three working methods

Professional window cleaners choose, per home and per window, the method that works best and most safely. In practice there are three.

1. Traditional with applicator and squeegee. The glass is soaped with an applicator and then dried in fixed strokes with a rubber squeegee; the edges are finished with a chamois or cloth. This method gives a crisp result and is suitable for ground-floor windows and for everything that can be reached from a safe standing position.
2. Telescopic pole with demineralised water. More and more window cleaners work with a long telescopic pole with a brush at the end, through which demineralised or osmosis water is pumped. This is water from which virtually all minerals have been removed. Because it contains no lime or soap, it dries without streaks and the glass does not need to be squeegeed dry. The window cleaner stays with both feet on the ground and can reach windows up to several storeys high this way. An additional advantage is that the brush cleans the frame as well.
3. Aerial work platform, cradle or rope access. For tall buildings, apartment complexes and facades that are hard to reach, the window cleaner uses an aerial work platform, or works from a building maintenance unit or cradle mounted on the roof. Some buildings use rope access techniques, in which the window cleaner descends the facade on ropes. Under the Arbobesluit (the Dutch Working Conditions Decree) this is only allowed if safer means are not reasonably possible, and it requires specific training and two separately anchored lines, usually attached to fixed anchor points on the roof.

Which method is most suitable depends on the height, the ground around the home, accessibility and the type of glass. A good window cleaner explains on the first visit how they will tackle the different windows.

What does a window clean include?

What a clean includes differs per company. So agree in advance what you expect. Consider:

• Outside of the windows. That is the standard. With homes, the inside is often only included on request or a few times a year.
• Frames, windows and doors: the paintwork, the bottom sills and the external sills. With the telescopic method this is often done automatically; with the traditional method it is sometimes a separate task.
• Roof windows and dormers, which can only be reached from the roof, with an aerial work platform or with a long pole.
• Conservatory, canopy and roof lantern. Glass roofs and polycarbonate sheets call for a gentle approach; polycarbonate scratches easily and must not be cleaned with aggressive products.
• Solar panels. In the Netherlands, rain washes a lot of dirt off the panels, but with a flat installation, a lot of falling leaves or birds, cleaning can make sense. Professionals work with demineralised water and a soft brush, without a pressure washer or abrasives. Before cleaning, first check the manufacturer's warranty conditions. More about panels in Having solar panels installed.
• Gutters and facade. Some window cleaners also offer gutter cleaning, facade cleaning or cleaning of roller shutters and sun blinds. That is usually a separate service.

Also agree what happens with windows that cannot be reached, for example because of planting, an extension or a neighbouring garden. A clear overview of which windows and components are and are not included prevents discussion afterwards.

Subscription or a one-off clean?

Most window cleaners work with a periodic subscription: they come by on a fixed round, for example every so many weeks, and you do not have to be at home if the outside is accessible. The advantage is that you do not have to think about it and that the windows never get really dirty, so every clean goes faster. With a subscription, pay attention to the notice period, to what happens if a clean cannot go ahead because of the weather and to how often the inside is included.

A one-off clean is handy after a renovation, before a move or sale, as a spring clean or for windows that you cannot reach safely yourself. A one-off clean of heavily soiled glass takes more time than a periodic clean, because deposits and construction dirt often have to be removed in several steps.

Working safely at height: what applies to the professional

Window cleaning is often work at height, and that is tightly regulated. The Arbobesluit requires employers, and for these rules also self-employed people without staff, to take measures against the risk of falling. With a possible fall height of 2.5 metres or more, under the Arbobesluit there is in any case a risk of falling and measures are mandatory; measures must also be taken at a lower fall height if there is a risk of falling, for example because of risk-increasing circumstances or openings in the floor. Collective measures, such as scaffolding, an aerial work platform or railings, take precedence over individual measures such as a harness.

According to the rules, a ladder is mainly a means of getting somewhere, not a workplace. A ladder may only be used as a workplace at height if safer work equipment is not justified, because of the low risk and either the short duration of the work or features of the location that cannot be changed. The ladder must then be stable, properly secured against slipping and the user must always have a firm handhold. That is an important reason why many window cleaners have switched to the telescopic pole: the tradesperson stays on the ground.

For you as the client this means: a professional window cleaner decides for themselves how to reach a window safely, and may refuse a window or suggest an aerial work platform if it cannot be done safely. That is not unwillingness, but professionalism. A company that starts working from a wobbly ladder on the third floor without any provision is precisely a reason to walk away.

Cleaning the windows yourself: the risks of the ladder

The health and safety rules apply to employers and the self-employed, not to you as a private individual. The risks, however, are just as real for you. According to the RIVM (the Dutch National Institute for Public Health and the Environment), consumer products play a role in around 60,000 accidents a year requiring emergency care, and about five percent of the victims fall from a portable stepladder or ladder. Cleaning windows is a typical scenario: you reach sideways, your hands are wet, the ladder stands on a slippery tile or soft ground and you have a bucket in your hand.

If you still want to clean the windows yourself, follow these rules of thumb:

• Clean everything you can reach from the ground, possibly with your own telescopic pole, and leave the rest to a tradesperson.
• Use a ladder in good condition on a flat, firm surface, at the right angle, and have someone hold the ladder.
• Do not reach far to the side; move the ladder one extra time instead.
• Do not climb a ladder in wind or rain or if you do not feel fit, and never work from a chair, table or window sill.
• Upstairs windows that you can only reach from the outside are better left to a professional. Tilt-and-turn windows can often be cleaned on both sides from the inside.

Which other jobs in and around the home you can do yourself and where you are better off calling in a tradesperson is explained in What can you do yourself during a renovation, and what is better left alone.

Apartment and VvE: who arranges the outside?

In an apartment complex, you often cannot reach the outside of the windows yourself. In many complexes, the vereniging van eigenaren (VvE, owners' association) therefore centrally arranges a window cleaner for the outside, and the costs are paid from the periodic contribution to the VvE. Whether that is the case for you depends on the deed of division and the division regulations: these state which parts of the building are common and which are private, and who bears which maintenance. Frames and windows in the facade are counted among the common parts in many regulations, but not everywhere. Decisions of the general meeting can also regulate how often the window cleaner comes.

If you want it done more often than the VvE arranges, you can usually hire a window cleaner yourself for the inside and the accessible parts. The VvE decides on work on the facade, such as fitting anchor points or a facade installation. More about the rules in an apartment complex in Renovating in a VvE apartment.

Rented home: what is the tenant's responsibility?

In a rented home, maintenance is divided between the tenant and the landlord. The tenant's small, day-to-day maintenance tasks are set out in the Besluit kleine herstellingen (Minor Repairs Decree). It states that washing and keeping clean the inside and outside of the window panes, frames and door posts is the tenant's responsibility, insofar as they are accessible to the tenant. The Dutch central government also lists washing and keeping clean the inside and outside of the window panes as a task for the tenant.

For windows that the tenant cannot reach themselves, such as the outside of windows high up in a block of flats, things are different: cleaning them is not one of the tenant's minor repairs. If the landlord has these windows cleaned, then according to the policy of the Huurcommissie (Rent Tribunal) they may only pass on the labour costs of the cleaning as service charges, and only if this has been agreed in the tenancy agreement. The costs of making the windows accessible, for example with an aerial work platform or cradle, remain at the landlord's expense. If in doubt, check your tenancy agreement and the overview of service charges, or ask your landlord or the Huurcommissie.

Weather and season

Window cleaners work all year round, but the weather does determine what is possible. In frost, the water on the glass can freeze and cleaning usually does not take place; in strong wind, working with long poles and ladders is unsafe. In light rain, many window cleaners using the telescopic method simply carry on, because after rinsing with demineralised water the glass contains no soap residue; a heavy shower straight after the clean can, however, leave spots again. With the traditional method, bright sunshine is actually a problem: the soapy water then dries too quickly and leaves streaks.

Many people have the windows done thoroughly in spring, after the winter with its road salt, soot and storms, and again in autumn after the falling leaves and the summer pollen. In the Maintenance calendar for your home you can see which other jobs combine well with this, such as cleaning gutters and checking the paintwork.

Choosing a reliable window cleaner and making good agreements

The window cleaner comes regularly, often when you are not at home, and sometimes walks through your garden. Reliability is therefore just as important as a clean result. Pay attention to the following:

• Registration with the KvK. A company should be registered in the Commercial Register of the Kamer van Koophandel (KvK, Chamber of Commerce); you can look this up yourself.
• Liability insurance. Ask whether the company has business liability insurance. A ladder that slides against a gutter, a scratch in a glass door or a damaged plant happens quickly. How insurance works for work on your home is explained in Renovating and insurance.
• Clear agreements about the frequency, which windows and components are included, inside and outside, what happens in bad weather and how and when you pay. Preferably have those agreements confirmed on paper or by email.
• Trade association and quality mark. The trade association for cleaning and window cleaning companies is Schoonmakend Nederland. Member companies carry the Keurmerk Schoon quality mark, which since 2022 has been the name of the former OSB quality mark; the mark sets requirements for, among other things, the financial and personnel administration, the application of the collective labour agreement and insurance, and is audited at least once a year by an independent inspection body. Window cleaning companies can also obtain the additional Glas & Gevel (Glass & Facade) certificate, with extra requirements for working safely at height. The register on the quality mark's website is authoritative. A quality mark is not a guarantee, but it is a sign that the company allows itself to be checked. Small self-employed window cleaners without a quality mark can also deliver excellent work; in that case, pay extra attention to the other points in this list.
• Working method and equipment. Ask how the company reaches the higher windows and whether it works with osmosis water, ladders or an aerial work platform.
• References. Ask neighbours or people in your street; window cleaners often work by neighbourhood.

For the back of the home, the window cleaner needs to be able to get into your garden. Agree how that works: via a gate that stays open or for which the company gets a key, via a back path or only when you are at home. If you hand over a key, record who has the key, how it is kept and that it will be returned if you cancel. Also think about a dog in the garden, loose garden furniture or plants in front of the windows, and an outside tap or power point if the window cleaner needs one.

A window cleaner by definition looks into your home from close by. If you want the clean to take place only on certain days or at certain times, for example not early in the morning by the bedrooms, agree on that. A regular round on a fixed day makes it predictable. A professional rings the bell or announces themselves when they start working in the garden, and does not leave ladders or equipment unattended.

In summary: choose a rhythm that suits the surroundings of your home, agree precisely what a clean includes, leave the high windows to a professional who works safely, and with an apartment or rented home, first check who arranges the outside. On VerbouwPro you post your job free of charge, and window cleaners from your region respond.