Air duct cleaning in Leidschendam-Voorburg

Offices and care: the profile of Leidschendam-Voorburg

Leidschendam-Voorburg has 78,229 inhabitants and ranks 49th of the 342 Dutch municipalities. Around 33 km² of land houses 2,399 people per km². There are 125.5 establishments per 1,000 inhabitants, more than in neighbouring Zoetermeer (115.2).

At 13.6%, trade and hospitality is smaller here than in most cities. The centre of gravity lies with offices and public facilities, and therefore with supply air and dry dust, not with grease.

After a renovation: why new ducts are not automatically clean

Anyone renovating an office or adding a wing often assumes that new ducts are clean. That is not always true. In its process manual for Fresh Schools (Frisse Scholen), the Netherlands Enterprise Agency (RVO) reports that air ducts in newly completed schools turn out to be contaminated with construction dust. The same risk exists in any renovation where ducts lie open while sawing and sanding take place.

Three handholds:

• Inspection at handover. According to TÜV Nord, an initial hygiene inspection belongs before a new installation is put into use and after a major modification.
• Cleanliness of new ducts. In annex A, EN 15780:2025 contains a separate table for new ducts, next to the tables for cleanliness classes, inspection intervals and acceptable levels.
• Arrange access during construction. Have inspection hatches fitted while the ceiling is still open. Eurovent recommends a maximum of 10 metres between openings.

Particularly when renovating an office building, it pays to include this in the specification beforehand. More about office buildings under office ductwork cleaning.

How much dust may an office duct contain?

An office manager wants a number. We have not consulted the text of the standard itself, but trade publications and a Finnish classification give guide values:

The Finnish values are measured with a pre weighed filter cassette. After cleaning you can demonstrate cleanliness with a surface comparison or a gravimetric vacuum test according to NADCA. Choose in advance which value you will work to and record it in the maintenance contract, so everyone knows when a duct counts as clean.

Duct cleaning Leidschendam-Voorburg in an occupied office

Most offices in the municipality stay in use during maintenance. That calls for an approach in which staff notice nothing.

1. Work after office hours or floor by floor. That keeps the rest of the building available.
2. Seal off what you are not cleaning. Duct balloons close off part of the duct; foam caps seal valves and diffusers.
3. Maintain negative pressure. Every section you clean stays under continuous negative pressure from an extraction unit, with HEPA of 99.97% at 0.3 µm if you discharge indoors.
4. Choose the brush for the material. Soft brushes for duct board and delicate sheet metal.
5. Leave the ceiling tidy. Resealable inspection hatches make the next round easier.

Everything for steps 2 and 3 is found under duct sealing and extraction in practice. For the machines themselves, look at duct cleaning kit explained.

What to agree with the tenant or occupier

• Which floors are worked on which evenings, and who opens the building.
• Where the extraction unit stands and where it discharges.
• Which ceiling tiles may be lifted and who puts them back.
• How the result is reported and which dust value was agreed.

Care and education in the town centres

With 1,955 establishments, government, education and care is the second largest sector in the municipality. For schools, every classroom must have a CO2 meter (article 3.143 of the Building Works Living Environment Decree, Bbl), and Fresh Schools calls for periodic technical and hygienic maintenance. With decentralised ventilation the installer has to visit every classroom to replace filters.

In care buildings with air humidification, legionella comes into play: article 4.87b of the Working Conditions Decree (Arbobesluit) sets out the measures, and the employer records them in a management plan. VDI 6022 mentions a hygiene inspection every 2 years with humidification and every 3 years without. Combine that inspection with the cleaning plan, but preferably have it done by a different party from the cleaner.

Ventilation duct cleaning Leidschendam-Voorburg and the neighbouring municipalities

Den Haag borders the municipality directly and, at 6,868 inhabitants per km², is far more densely built up; see ductwork cleaning for Den Haag businesses. Zoetermeer has a higher share of industry and energy (14.2%); see air duct cleaning in Zoetermeer.

An overview of all municipalities can be found under air duct cleaning by city in practice. For a quote, a callback request or a question about equipment, contact Lamers in Zelhem, or ask for duct cleaning advice for businesses straight away. Mention whether your buildings are mainly offices, schools or care premises, and whether a renovation is coming up.