Roof cleaning: compare quotes and prices

When is roof cleaning worthwhile?

Light discolouration and isolated moss patches may mainly be cosmetic. The situation differs when leaves or growth obstruct drainage, deposits collect around junctions or an inspection identifies a specific need. Not every roof therefore needs routine cleaning of its entire surface.

Leaks, broken tiles or a badly aged covering call for an assessment of repairs or replacement first. Cleaning does not fix those defects. Conversely, moss alone is not sufficient reason to replace the whole roof.

Define the scope: the entire roof, selected affected areas or just drainage points. A local patch of dirt should not automatically turn into a large cleaning package.

The roof material sets the limits

Tiles, metal, slate, fibre cement and membranes do not tolerate the same treatment. Coating and condition also matter. The contractor should follow the guidance for the particular covering and assess a suitable test area where necessary.

• Older fibre cement. It may contain asbestos. Do not brush or pressure-clean it yourself. Have a specialist establish whether cleaning is appropriate and under what conditions. Asbestos-containing sheets should preferably be replaced rather than cleaned where possible.

Clean gently and manage the residues

A quick visual improvement does not prove that a method is suitable. Pressure, water direction and mechanical action must suit the material. Excessive force can damage surfaces or drive moisture beneath the covering. Pressure washing is therefore not a universal recommendation.

In Switzerland, biocidal products against algae and moss must not be used on roofs. A product advertised as a roof treatment is not automatically permitted. Ask what method will be used and how the contractor will address local requirements.

Removed material should not simply be washed into the gutters. Collection, removal and management of cleaning water need planning. Even without added chemicals, material removed from the roof can contaminate the water. Clarify drainage protection, the surrounding area and disposal before work starts.

Before the appointment, agree what access and working space the contractor needs and whether an on-site water supply will be used. Clarify who will move vehicles or garden furniture out of the work area and protect sensitive features. The contractor sets out the restricted area; children and pets stay outside it during the work. Also agree how a weather-related postponement will be communicated and whether it could incur charges.

A coating is not an obligatory next step

Cleaning, impregnation and coating are different services. A coating does not restore structural strength to crumbling material or repair the roof build-up. A more uniform appearance is not enough to justify applying it.

If an additional treatment is proposed, ask about its specific benefit, compatibility and possible drawbacks. Clarify effects on the covering, future work and disposal. A separate quotation lets you decide without implicitly buying an extra package.

How much does roof cleaning cost?

Area, shape, height, access and workload determine the price. The relevant quantity is the roof surface being cleaned, not the living area or simply the building footprint. Existing documents or an estimate are enough initially; the contractor can establish exact measurements.

Two Swiss provider examples checked in October 2026 use different models: one publishes an indicative CHF 8–17 per m²; another lists CHF 12 per m² with a CHF 1’200 minimum. Their service pages do not fully clarify VAT and all additional costs. These are neither confirmed totals nor a general market price range.

Under the second model, an assumed 60 m² would calculate to CHF 720, but the minimum makes it at least CHF 1’200. Unresolved extra costs and VAT must still be clarified before ordering. A seemingly cheap square-metre rate can therefore mislead for a small area.

• Access and protection. Scaffolding or platform, safety, protection of surroundings and setup time.
• Work. Defined area, soiling, cleaning and any local additional tasks.
• Completion. Residues, cleaning water, surrounding-area cleanup and documentation.
• Price terms. Travel, minimum charge, VAT and separately approved extra work.

Prepare a useful enquiry without unnecessary effort

Roof shape and material, approximate area, building height, known access and the reason for cleaning help with an initial quote. An unidentified material can remain open for assessment. You do not need to climb onto the roof or take a sample yourself.

The contractor then checks the covering, condition, safe access and protective measures. A roof hatch or existing anchors alone do not establish that work can be carried out safely. On a green roof, distinguish vegetation to retain from unwanted growth.

Agree who records visible damage and how it will be handled. Gutters, solar panels and repairs are included only when expressly commissioned. The appropriate outcome is a clearly defined service, not an unsupported promise of an as-new roof.

An enquiry might read: “Our two-storey house has a tiled gable roof. Existing documents indicate about 130 m² of roof area. We can see moss on the north side and leaves collecting near the gutter; we are not aware of any leaks. There is a carport beside the house and access is narrow. We have photographs taken from the ground. Please assess which areas actually need cleaning and itemise access, protection and waste removal. Quote separately for gutter cleaning; we do not currently want a coating.” This is an example to start the discussion, not a specification of the method or price.

At completion, ask to see the treated areas and any sections left out through agreed photographs or a brief report. Have the specified deposits been removed, affected outlets cleared and the work area tidied with residues removed? Record pre-existing damage separately from newly identified defects. Some discolouration may remain visible after cleaning; clarify outstanding points and any next steps with the contractor rather than climbing onto the roof to inspect it yourself.