››  ››

Cleaning your Decking. Keeping it in good condition.

The surface of timber decks becomes exposed to the elements such as sunlight, rain, snow and frost. This will inevitably lead to a deterioration of the colour if nothing else.

Like most things outside, decks will respond to a maintenance schedule that involves cleaning and supplemental treatment.

Discolouration is the obvious problem - all un-stained timber outside eventually turns a grey colour. Protective action can help to allay this problem, which is caused in the main by fine dirt particles entering the microscopic 'pores' of the timber. See our article on Decking Oils

Decks need periodic attention to keep them looking good. We take you through the process of caring for and cleaning your decking.

Decks like this Ipe hardwood deck will need regular maintenance and cleaning to maintain the colour
Picture courtesy of 

The timber itself loses colour as ultra violet rays from the sun react with the timber. In this case, simply cleaning your deck will not restore the original colour. Though it will make it more attractive!

Discolouration of the deck timber has many causes - dependent upon the area in which you live - together with a number of biological causes.

Planters - Tubs and Pots etc on Timber decks

When you move planters about on your deck, you are often left with areas that have not 'faded' at the same rate as the rest of the deck, or patches of algae growth under where the planters were. The damp areas under planters are ideal for algae.

One way to prevent these problems is to place the planters on metal plant stands - or even the small terra cotta 'feet' that are available.

Algae Growth

Algae growth - after a damp winter for instance - can soon be got rid of with a weak solution containing ordinary household bleach. A cupful of bleach to 2 pints of water approx, usually does the trick on decks - and patios!. Best applied with a brush, and make sure that it is all rinsed off after cleaning.

Rust Marks

Rust marks can be removed using commercial rust remover, or even a light sanding on a dry day. Best paint the undersides of the metal furniture to prevent this happening.

Grease Marks

Oil cleaning fluid - such as that sold for car engine cleaning - can remove stubborn grease marks. Normal domestic washing-up liquid will also work wonders - if applied with suitable quantities of elbow grease. 

Before treating any deck, the deck should be thoroughly cleaned.

How to Clean a Deck

There are several preparations available fro DIY stores or Decking Specialists which to clean your deck. Go for the brand names, or reputable DIY stores own brand. Do not attempt to treat your deck or stain it without firstly cleaning it.

An alternative, is to use a weakened solution of TSP (trisodium phosphate) which can be obtained from any good paint shop. (It is used by pro painters to clean paintwork). Add a little household washing-up liquid to ensure a deep penetration. Try a small area first, and use as directed on the container.


This is best applied with a normal household broom, but then 'scrubbed' in with a general hard broom - such as is normally used for patios and exterior areas.

Do not use any chlorine based bleach, for whilst this will clean your deck of algae and mildew in particular, it will also break down the lignin in the deck timber - which holds the wood together!

A weak solution of Citric Acid will help to 'brighten up' old greyed timbers. Most important 0 - it is a non hazardous way of cleaning your deck. There are also some proprietary brands of wood bleach available, that will do the job.

Hydrogen Peroxide - which also has other lightening uses - will do wonders for lightening old timbers and in particular is good for the older darker deck timbers. It evaporates away, leaving no residues.

Most fungal growth can be treated with a general garden fungicide! If you use a combined Fungicide/Insecticide to clean your deck, then you can also kill of many 'hidden' insect pests lurking under the timber. This treatment does nothing to lighten the wood or to actually clean it of dirt - simply fungi/mildew and insects. It is not for cleaning the deck - simply to rid it of any infestation

A jet washer can be used for cleaning decks  BUT it must not be a heavy duty one. Something smaller than 1500 psi with a wide fan jet will be suitable for most deck cleaning jobs. Anything more powerful will leave the timber with a 'wooly' finish, as it will destroy the wood fibres. The result will be a deck that is very difficult - if not impossible - to clean or to treat.

Once the deck is clean - then and only then - you can think about a long term treatment regime to enhance the colour and longevity of your deck. Even after a suitable treatment application, regular cleaning of your deck is important to maintain the colour of the deck timbers.

Oil treatment for your clean deck 


Contact | Employment | Sitemap | Links | Privacy Policy |