We encourage customers to allow the timbers to dry out then apply a suitable waterproof coating (below 18% moisture). Pressure treatment is designed to protect against rot and insect attack not make the material impervious to water.


You should be aware that pressure-treated products will shrink if they are used in making something whilst still wet, this can create gaps as the material dries out allowing moisture to ingress.


Pressure preservative treatment is designed to prevent rot and insect attack to give softwood construction and landscaping timber products an extended and low maintenance service life. The treatment is not intended to perform as a waterproofing agent. You can purchase of waterproofing agent here.


Although the TANALITH wood preservative used in the pressure-treatment process is of the highest quality, it doesn’t protect timber from the effects of weather. Without additional protection UV rays from the sun will weather timber changing the colour to silvery grey. Moisture will negatively affect the lifespan and performance of a timber product, so it’s essential to add a high-quality protective water-repellent. You can purchase UV protect here.


When using pressure treated cladding timbers in the construction of sheds or garden buildings the following guidelines should be followed to help prevent any water ingress.


  • The Timber Research and Development Association (TRADA) recommends a 16-19mm nominal thickness for cladding timbers.
  • Nail heads should only be driven marginally below the surface of the cladding timbers.
  • A suitable airflow should be allowed throughout the structure to assist on-going drying.
  • The dry, external timbers can have a water ingress protection added with the application of an appropriate and well maintained water repellent coating. This would involve a proprietary water repellent coating product which could be applied to the dry external timbers following the relevant manufacturer's guidelines.


Softwood is a natural product that can twist or warp through changes in climatic conditions. To minimise this, our products should always be sited on firm and level ground that is away from areas where water collects.


During the pressure-treatment process, some grain may be raised. If desired this can be removed with a little light sanding.


Green marking may become visible as salt leaves the timber whilst it dries following pressure treatment. It will fade over time and does not affect the performance of the product. Remove any of this solid salt residue with a wire brush or light sanding prior to painting. A micro-porous (breathable) coating will allow any further moisture to evaporate out through the paint.


Changes in the weather may cause fixings to loosen but these can be tightened up as appropriate.


Softwood may at times develop cracks in the surface called ‘shakes’. These are a natural occurrence and can be prevalent during changes in temperature and humidity as the timber expands and contracts. Please note that this will not affect the performance or durability of your product. If desired, any ‘shakes’ can be rectified by applying a proprietary wood glue making sure to follow the manufacturer’s instructions at all times. Once dry this can be sanded to a smooth finish. Application of a high-quality protective water-repellent coating can reduce cracking by stopping moisture penetrating into the timber, one of the causes of this natural process in timber products.


Over time the colour of your product will gradually weather, first to a honey brown and then to a silver grey. This does not indicate any loss of preservative protection. To keep the original colour of your timber you will need to apply a clear wood paint, oil, or stain, that has UV blockers to stop the greying process.


A quality wood paint or oil can be applied to your product to provide protection and colour. Garden designs can benefit from a coloured timber product whether it be a bench, arch, arbour or building, complimenting planting and adding year-round colour. Apply in dry weather and follow the manufacturer’s full recommendations.


Some staining can occur on paint coatings as tannins and/ or sap/resin come out of the new timber. This is a natural process but a stain-blocking primer and/or knotting agent can be applied prior to painting to minimise potential staining.


Pressure treated products can be painted with a high- quality wood treatment as long as the moisture content is below 18%. Always check with the manufacturer as some treatments can cause the timber to warp or split if it hasn’t fully dried.


Sheds are pressure treated but will need additional protection from the weather and in particular, moisture penetration. Apply a high-quality water-repellent paint or oil to help seal the shed, making sure that joints and fixings such as nails and screws, are well covered. A good microporous coating will allow any internal moisture to evaporate out through the external coating.


When applying a wood paint, oil, or stain, pay particular attention to horizontal surfaces and areas that can collect water. Coatings will degrade quickest on a horizontal plane with cheaper products wearing faster. Vertical surfaces can last for years before a maintenance coat is required.


Maintain your timber product on an annual basis, or sooner if required. Clean paint coatings with soapy water and apply a maintenance coat when required. The better the quality the more years it will be before a maintenance coat is needed. Untreated timber products should be cleaned with soapy water or a wood cleaner.


In the unlikely event a product is faulty or damaged upon delivery, any issue must be advised within a reasonable period. The definition of reasonable depends on the product and how obvious the fault is, however, even with more complex items you should work on the basis that this is no more than three to four weeks from receipt. This does not affect your statutory rights.


Hope this helps - but if you have any further queries, please do not hesitate to contact us.