Identify the surface
Establish whether the boards are timber or composite and note age, wear and previous finishes.
Southampton · Bournemouth · Hampshire · Nearby Dorset
Professional decking cleaning, built around the material.
Timber and composite decking can respond differently according to age, surface condition, previous coatings, organic growth and weathering. We inspect those factors before choosing how to clean the surface rather than subjecting every deck to maximum pressure.
Cleaning
From £6/m²
Minimum charge
£150
Choose Decking in the existing Exterior Care estimator.
Material identification · Controlled cleaning · Clear expectations · Practical aftercare
Control the clean
Match treatment, flow, pressure, distance and technique to the deck rather than using one setting.
Set realistic next steps
Review drying, remaining marks and any future protection without assuming every deck needs a coating.
Common decking conditions
Understand the boards before choosing the method.
Dirt and general weathering
Foot traffic, airborne dirt and repeated exposure can leave boards dull, uneven-looking or discoloured.
Green algae and organic film
Shaded or damp areas can develop surface growth that changes appearance and may feel slippery underfoot.
Moss and heavier build-up
Organic matter can gather between boards, at edges and in sheltered areas, sometimes needing targeted preparation.
Grime in grooves and texture
Board profiles and textured finishes can hold contamination that needs careful cleaning rather than a rushed pass.
Local staining
Food, planters, metal furniture and other sources can leave marks that may improve without disappearing completely.
Previous oils, stains or coatings
An existing or failing finish can change how the surface responds and may limit the result available from cleaning alone.
Why the material matters
Timber and composite decking need different care.
The safest effective method starts with the boards themselves—not an assumption that every deck will respond in the same way.
Timber decking
Read the grain, wear and previous finish.
Age and overall condition, grain, surface vulnerability, weathering, previous coatings and damaged boards all affect the cleaning approach and achievable result.
Composite decking
Respect the product and surface finish.
Construction, manufacturer guidance, surface finish, staining and previous cleaning or treatments can change the approach. Composite products should not be treated as though they are identical.
Pressure and technique
Pressure-assisted cleaning can be useful. Maximum pressure is not the goal.
Clean effectively without forcing the surface.
Pressure, distance, flow, treatment and working technique need to suit the type of decking and how it responds during cleaning.
Overly aggressive technique can cause avoidable damage, particularly on softened timber, worn finishes, vulnerable edges or already deteriorated boards. That does not mean pressure washing is inherently wrong for every deck.
The aim is to remove the build-up while respecting the boards underneath it.
The method
Seven clear stages from inspection to final review.
- 01
Identify material and inspect condition
We establish the board type and review age, wear, fixings, joints and damaged areas.
- 02
Check finishes and vulnerable areas
Previous coatings or treatments, softer sections and deteriorated boards are noted before work begins.
- 03
Protect the surroundings
Furniture is cleared and nearby walls, glazing, plants and drainage routes are considered.
- 04
Use pre-treatment when useful
Organic growth or established grime may receive a targeted product suited to the surface.
- 05
Clean with a controlled method
Pressure, flow, distance and working technique are adjusted to the boards and how they respond.
- 06
Rinse and detail junctions
Accessible grooves, edges and connections are checked as residue and loosened contamination are rinsed away.
- 07
Review the cleaned deck
We inspect the finished surface and discuss drying, maintenance and sensible next steps.
Organic growth and slipperiness
Remove the build-up without promising it can never return.
Algae, green film and moss can accumulate on decking, particularly in shaded, damp or slow-drying areas. That build-up can make the surface unpleasant and may contribute to a slippery feel.
Cleaning can remove surface growth and grime, while routine care and managing debris help reduce future accumulation. Weather, moisture and the surroundings mean growth can return, so a permanent non-slip outcome or fixed regrowth period cannot be promised.
Aftercare and protection
Decide what comes next only after the boards are clean.
Material, existing finish, surface wear, retained moisture, drying, the finish you want and manufacturer requirements can all influence future care.
A protective product or further finish is not included automatically and should be assessed separately. The estimator flags timber/composite sealing selections for closer review rather than treating protection as a standard decking add-on.
Black Haven does not assume that every cleaned deck needs oiling, staining, sealing or refinishing.
Transparent guide pricing
Build your decking estimate.
Choose Decking, add approximate measurements and identify the boards as Timber or composite. Photographs help Black Haven confirm material, build-up and any areas that need a closer review.
- Decking cleaning
- From £6/m²
- Minimum job charge
- £150
These guide values come from the same area and material rates used by the Exterior Care estimator. Final scope depends on measurements, board type, visible condition and photographic review.
Practical expectations
Prepare the area and allow for real drying conditions.
Access and clear working space
Equipment needs reasonable access, while furniture, pots and loose items should be moved from the agreed area.
Water and drainage
An exterior water supply may be required, and runoff routes are reviewed before the cleaning method is confirmed.
Walls, glazing and plants
Nearby finishes, windows and planting are considered during preparation, treatment and rinse-down.
Weather and drying
Shade, airflow, temperature, moisture and rainfall all affect how quickly the boards dry after cleaning.
Older or damaged boards
Cleaning cannot repair split, softened, loose or deteriorated boards, and vulnerable sections may limit the method.
Final review
The agreed area is checked after cleaning so remaining marks, drying and future care can be discussed clearly.
Before booking
Decking cleaning questions.
How much does decking cleaning cost?
Black Haven decking cleaning starts from £6 per square metre, subject to the £150 minimum job charge. The guide depends on measurements, material, visible build-up and any areas that need closer review.
Can you pressure wash decking?
Pressure-assisted cleaning can be appropriate, but the setting and technique must suit the deck. Surface wear, distance and flow all influence the approach.
Can you clean both timber and composite decking?
Black Haven assesses both timber and composite decking. Products and board constructions vary, so we check the boards and their finish before confirming the method.
Can you remove algae from decking?
Green algae and organic film can usually be treated and cleaned, with preparation adjusted to the level of build-up. Shaded or damp conditions mean future growth can return.
Can you remove moss from decking?
Moss and loose organic build-up can be addressed when present, including around accessible edges and board junctions. Cleaning does not prevent spores or new growth from returning later.
Will cleaning make slippery decking safer?
Removing surface algae, moss and grime can improve the cleanliness and feel of affected decking, but no permanent non-slip result can be guaranteed. Board design, wear, moisture and future growth still matter.
Can you remove stains from decking?
Local marks are assessed individually. Some respond well to cleaning or targeted treatment, while absorbed, historic or coating-related stains may improve without disappearing completely.
How long does decking take to dry after cleaning?
There is no universal drying time. Material, shade, airflow, temperature, board spacing, retained moisture and weather all affect when the deck is sufficiently dry.
Can previously oiled, stained or coated decking be cleaned?
Potentially, but the existing finish may be worn, patchy or incompatible with some methods. We inspect it first and explain if cleaning alone cannot create an even appearance or remove the old coating.
Does decking need treating after it has been cleaned?
Not every deck needs or accepts the same treatment. Any protective product or further finish should be assessed separately against the material, existing coating, moisture, the finish you want and manufacturer guidance.
Start with the boards
See what your decking needs from a professional clean.
Build a guide from area, material and visible build-up. Black Haven reviews the surface and photographs before the final scope is agreed.