Do they understand the surface?
A good exterior cleaner should be able to explain how they intend to clean your particular surface.
Cleaning block paving isn't the same as cleaning render, timber, UPVC or roof tiles.
Be wary of anyone who suggests exactly the same method for everything.
Do they have appropriate insurance?
Exterior cleaning involves water, machinery, cleaning products and sometimes working at height.
It's reasonable to ask whether the company has appropriate insurance for the work they carry out.
A professional business should be comfortable answering this question.
Do they use the right equipment?
Professional equipment can make a difference, but expensive machinery isn't automatically a guarantee of quality.
What's more important is whether the equipment is being used appropriately.
The right nozzle, pressure, cleaning solution and technique can all affect the finished result.
Do they protect surrounding areas?
A professional cleaning job should consider what is around the surface being cleaned.
Depending on the job, this may include:
- Plants and lawns
- Windows and doors
- Garden furniture
- Vehicles
- Neighbouring surfaces
- Drainage areas
Preparation and protection are important parts of the job rather than an afterthought.
Do they give realistic advice?
A good contractor shouldn't promise that every stain will disappear or that every surface will look brand new.
Some staining is permanent, some surfaces have already weathered, and some materials have limitations.
Honest advice is much more useful than unrealistic promises.
Is the quote clear?
A good quote should make it reasonably clear what work is included and whether anything additional may be required.
For example, block paving may require re-sanding after cleaning, while particularly heavy contamination may require additional treatment.