Mercia GuaranteeMercia Guarantee


Mercia Garden Products offer a conditional 10-year anti rot warranty. To comply with the warranty, you must register your building, along with applying a high-quality wood preservative and high-quality wood topcoat paint once the building has been assembled. A high-quality wood topcoat paint must be applied annually thereafter to protect against water ingress and weathering.

All our garden buildings have been designed and manufactured with care and attention to the be the perfect addition to your outdoor space. To ensure you get the best out of your garden building and increase the longevity, we advise that once it has been installed you treat it as soon as possible and annually to waterproof it and prevent the timber from deteriorating. This is required to maintain the anti-rot guarantee.

Dip treated buildings - This is the process in which we apply a water based colourant (light orange) for protection whilst in storage and transit. This is not a preservative therefore the building will require a preservative to protect against rot and decay and a waterproof top coat to prevent water ingress. This is required to validate your 10 year anti-rot guarantee.

Timber is cut ready for treatment.

Timber is dipped into a cylinder containing preservative.

Preservative is absorbed into the surface of the timber.

Timber is removed from cylinder containing preservative.

Timber is left to air dry.


Pressure Treated buildings - Pressure treatment is a high pressure chemical process designed to preserve exposed timber. The pressure treatment process impregnates preservative chemicals deep into the timber fibres to protect it against the elements. This process provides your building with 15 years anti rot guarantee, providing you apply a waterproof top coat once installed and annually thereafter.

Timber is loaded into a chamber and a vacuum empties timber cells of air.

Timber is flooded under vacuum with preservative.

Preservative is forced deep into timber using hydraulic pressure.

Another vacuum extracts excess preservative.

Timber is left to dry under a low pressure.


Log Cabins/Insulated Garden Rooms- Are supplied untreated (pale timber) and require a preservative to protect against rot and decay and a waterproof top coat  to prevent water ingress. This is required to validate your 10 year anti-rot guarantee.


Why use a wood preservative?

Preservation of wood that’s outdoors is vital. Early care will help protect your garden building, improve its appearance and ensure maximum longevity. Insects, moisture, salt, and changing weather can have dramatic effects on the stability and appearance of your shed.

Preservative treatments penetrate deep into the timber and regulate the moisture in the timber to reduce rot, decay, fungi and bacteria growth, swelling, twisting and movement of the wood.


Handy hint - Applying a preservative treatment to both the inside and outside of your garden building will give it maximum protection.



Why use a waterproof top coat?

A good quality waterproof top coat nourishes and seals the external timber against water ingress. The top coat repels water, preventing it from penetrating and weathering your garden building. This will ensure your garden building looks great for years to come.