External timber doors are popular thanks to their attractive appearance, thermal performance and durability. They are available in a wide range of  types, from solid timber to wood based LVL or insulated panel cores faced with wood veneers or thicker wood elements.

External doors are subject to demanding stressors due to repeated opening/closing, as well as differential temperatures and humidity  conditions on their external and internal faces. Solid timber doors use thicker sections to resist the movement induced by these demanding conditions. External doors based around a wood core of LVL or laminated wood sections are generally more stable.

External doors are available as sperate components assembled on site or increasingly as factory assembled set.  A ‘door set’ is a complete door system that is defined by BS EN 12519 as ‘supplied complete with all essential parts from a single source’. The door system typically includes the sub frame, door leaf, hinges, hardware, glazing .

Most common wood finish for external doors is Oak but other durable hardwood species Iroko, Walnut or Sapele are available. Less durable species such as Pine, may be suitable for external use where specialist coatings can provide sufficient weather protection.

Modified timber brands such as Accoya are also becoming a popular choice for external doors, thanks to their long lifespan and moisture stability which increases maintenance intervals.

One of the benefits of timber external doors is that they can be refinished  multiple times, and that they generally feel more ‘solid’ than composite or UPVC alternatives.

From traditional sash to modern feature and roof variants, wood windows give developers, contractors and homeowners a huge range to choose from, but what are the critical factors when making that choice.

Wood used – The type and quality of wood used to manufacture the window frames and other components will be the most important influence on the performance and durability of the window. All windows particularly those which open to provide ventilation are precision engineered products and therefore stability is key.

Hardwoods have traditionally been seen as the more stable material but the emergence of laminated and engineered softwood window components are raising the game in terms of stability and quality of finish. The use of modified wood products such as Accoya in the surfaces of  the window which face weathering bring the added benefit of greater moisture resistance and therefore extended durability.

Finishing systems – Specialist coatings when combined as an integrated finishing system first applied under factory conditions are really pushing the boundary of what can be achieved not only in terms of desired service life but also importantly extending the time between scheduled maintenance.

Location – The design of the window, be it casement, bay, roof or fixed facade has to align with its location both within the building and geographically. Exposed locations subject all external joinery but especially windows to much greater weathering and moisture penetration and therefore increase the need for more careful design in terms of shedding water and facilitating maintenance. The location of the window within the building must be reflected in its design with the latest generations of roof windows able to

Desired service life – all of the above factors will influence the service life which can be achieved but the stability of materials used and the finishing system that is applied will certainly have the biggest impact. A 60 year service life can be achieved by making the right specification choices, with members of the wood window alliance leading the field in terms of performance and longevity.

As with timber external doors one of the greatest benefits of wood windows is that they can be maintained and refinished multiple times. This feature greatly extends the potential service life of wood windows often allowing more thermally efficient glazing units to be installed into refurbished frames.