Timber Box Sash Windows

Accoya

This timber is the world’s leading high technology long life wood created from sustainably sourced, fast growing softwood in New Zealand.
The timber has an average density of 510kg/m3.

Accoya has extremely low thermal conductivity and is treated to match or exceed the durability and dimensional stability of the very best tropical hardwoods.

Accoya undergoes a propriety non-toxic acetylation wood modification process in the Netherlands that permanently modifies the wood structure to the core. This is achieved by reacting the wood with acetic anhydride which is forced throughout the body of the wood so that when Accoya wood is cut or jointed there are no exposed non-acetylated surfaces in any dimensions and does not weaken or affect the natural look of the wood.

This process negates any need to apply additional chemical preservatives. Once complete the ability of the wood to absorb water is greatly reduced rendering the wood more dimensionally stable because it is no longer digestible, increasing the lifespan of the timber.
This process also produces a harder and more consistent structure making it more resistant to denting and damage, produces a finer finish under sanding and the lack of water absorption from the paint leads to a better quality paint finish than hardwood and an increased lifespan of the paint coating in the longterm.

Due to the acidic nature of the coating, stainless steel fittings need to be used to help prevent corrosion.

Engineered Redwood

Our most commonly used softwood timber for frames and sash. This timber
is made up of several different layers of dimensional timber glued and laminated together making the timber stronger, dimensionally stable and longer lasting.
The timber is engineered to remove knots and other unsightly blemishes and defects which reduce wastage compared to natural timber and is much more environmentally friendly.

The timber has an average density of 510kg/m3.

Engineered Redwood is more durable and lessens the effects of seasonal movement and shrinkage whereas natural timber can continue to expand and contract depending on the environment it is in.

After the primers and microporous water based paint finishes are applied they will last for the lifetime of the window with the correct maintenance.

Red Grandis

Our most commonly used hardwood timber, Red Grandis (Eucalyptus Grandis, to give it its botanical name) is a South American hardwood sourced from sustainable and carefully managed timber plantations.

Red Grandis is a high grade, clear, knot free and uniform timber with a consistency of colour, appearance and workability. Red Grandis offers a legal, sustainable and fast growing alternative to uncertified Sapele or Meranti timber.
The sapwood is light grey or cream in colour and the heartwood is of a light red to pink in appearance.

Independently tested by a third party in the UK by TRADA (Timber Research and Development Association), Red Grandis achieved durability class 2 to 3 – durable to moderately durable, showing the hardwood to be a naturally
durable and fungi resistant timber. During structural testing, BRE (Building Research Establishment) tests also produced results of D35 for strength and stiffness properties and for C36 density.
Red Grandis can easily be stained to resemble Oak, Sapele, Meranti and a variety of other timbers or if left untreated can weather to a pleasing silver grey colour.