Looking after your decking

Decking provides the perfect enhancement to many homes. Are you confused about how to treat your new timber decking?  Then don’t be.

We supply and install decking.  We have completed many projects where our customers ask about maintaining the deck. I will come to that later,  but firstly it is important to appreciate how the timber is treated prior to installation.

Pre-treatment of decking boards

The timber supplied for decking is generally softwood which has been pretreated against deterioration and rotting. Historically, some fairly dangerous chemicals were used in this process. These chemicals included arsenic and volatile solvents to ensure penetration into the timber. Nowadays water based systems are used which allow for less harmful chemicals to be used. The application is usually under pressure to get into the grain of the wood.  This is to ensure that it will remain in good condition for years to come.

Often we hear the term ‘Tanalised’ timber. This is actually a trademark referring to the use of a chemical ‘Tanalith E ‘ which has been around for over 50 years. The main ingredient in preserving timber to pressure treatment today is copper.

This is responsible for a greenish colouring on the timber on many occasions. Other chemicals and Biocides are added to help extend the range of protection offered. Generally these chemical substances are not harmful to humans and animals. You do need to be careful that they are not discharged into watercourses as they may be harmful to fish and amphibian life

Weathering in the decking

Many customers are concerned about how the deck will weather in once it has been installed. Water based pressure treatment of tender offer means that it arrives on site in a wet condition and therefore is prone to shrinkage as it dries out. As a result when we fit a deck we use smaller spacing than we would have done a number of years ago. This allows for some shrinking to take place. In the initial light green hue on the timber will wither away to a light honey brown overtime. If the timber is left without any further treatment most Scots pine based boards will turn to a silver grey colour.

There are many different treatment products available to protect decking. As the timber is already preserved as detailed earlier the main aims of many of these products is to:

  1. Extend protection, and
  2. Enhance the look of the deck

Commercially available stains can be found here:



Be careful to chose between decking oil and decking protector. In the main decking oils are spirit based and need to penetrate the grain of the wood to form a bond in order to provide protection. Therefore the timber must be able to absorb the liquid so any water based treatment or factory treatment must have had time to lose its resistance to penetration before you apply it.

Decking oil
Decking oil enhances the beauty of the wood grain

Decking protector my, on the other hand be a water based liquid. Usually these treatments are a suspension of colloids and waxes which may be immediately applied after the deck has been laid and will key to the surface of the timber even if it has recently been factory treated with water based materials.

There are also a range of coloured deck stains which can be used to introduce fresh colour to the garden or even used to stain old decking to prolong its life provided that it is structurally sound.

See examples of decking we have installed

4 Replies to “Looking after your decking”

Leave a Reply

Your email address will not be published. Required fields are marked *