Clean your front exterior.

Professional exterior cleaning, often referred to as "soft washing" or "facade restoration," removes these organic growths and stains safely. This guide covers everything from typical costs for 2025 to the specific regulations you need to know to protect your home’s kerb appeal.

What Does the Work Involve?

• Site Assessment: A technician inspects the facade material (e.g., K-Rend, brick, or stone) to determine the safest cleaning pressure and chemical ratio.
• Surface Protection: Masking off external power sockets, covering vents, and pre-wetting nearby plants to protect them from cleaning solutions.
• Chemical Application: Applying a specialist biocide or detergent using low-pressure "soft wash" equipment to kill organic spores at the root.
• Agitation: Using soft-bristled telescopic brushes to gently lift stubborn dirt and carbon deposits without scouring the surface.
• Controlled Rinse: Rinsing the walls, windows, and frames with deionised water or low-pressure steam to leave a streak-free finish.
• Grounds Tidy: Washing down the driveway, steps, and paths to remove any run-off debris or chemical residue.

Typical Costs

Pricing for exterior cleaning depends heavily on the size of the property and the level of organic growth. Most UK contractors charge based on the number of storeys and the total surface area to be treated.

Note: Prices include VAT at 20%. Factors such as heavy ivy removal or the need for a water bowser (if your external tap is inaccessible) will increase the final quote.

How Long Does It Take?

• Small Terrace: 2–4 hours. This usually involves a single operative using a water-fed pole system.
• Semi-Detached: 4–6 hours. This allows for chemical "dwell time" to ensure all algae is neutralised.
• Large Detached: 1–2 days. Larger projects often require multiple stages of cleaning and rinsing to ensure a uniform finish.

DIY or Professional?

While hiring a pressure washer might seem cost-effective, it is the most common cause of damage to UK homes. High-pressure water can strip the finish off modern renders, blow mortar joints in old brickwork, and force water into wall cavities, leading to damp issues.

Expert Tip: Professional "soft washing" uses chemicals rather than pressure. This is far safer for your home's structural integrity and keeps the surface clean for significantly longer by killing the spores.

Professional tradespeople also carry the correct insurance and have the reach equipment to clean second-storey windows and gables safely without the risk of falls.

Choosing the Right Tradesperson

• Check Qualifications: Look for City & Guilds accreditation in the Safe Use of Biocides or membership in the Professional Outdoor Cleaners Association (POCA).
• Insurance: Ensure they have Public Liability insurance (minimum £2 million) that specifically covers "damage to the property being worked upon."
• Method Statement: Ask for a written description of how they intend to clean your specific wall type—avoid anyone who suggests "blasting it" with a high-pressure nozzle.
• Questions to Ask:
  • Are your cleaning chemicals biodegradable and safe for pets?
  • Do you provide a guarantee against the return of algae (usually 12–24 months)?
  • Will you be using your own water supply or do you need access to my outdoor tap?

UK Regulations

• COSHH: Contractors must follow Control of Substances Hazardous to Health (COSHH) regulations when handling biocides and bleach-based cleaners.
• Work at Height: Any work above ground level must comply with the Work at Height Regulations 2005, prioritising ladders or poles over more dangerous methods.
• Environmental Agency: It is illegal to allow certain chemicals to enter the main surface water drainage system; pros should use "bunding" or neutralising agents.

Common Problems

• Chemical "Tiger Stripes": Caused by uneven application of detergents, leaving visible vertical streaks on the render.
• Plant Die-back: If plants aren't properly shielded or pre-soaked, chemical run-off can kill lawns and flower beds.
• Window Seal Damage: Excessive heat from steam cleaners or high pressure can perish rubber seals, leading to misted double glazing.
• Efflorescence: Incorrect cleaning can draw salts out of brickwork, leaving white, powdery stains that are difficult to remove.

Frequently Asked Questions