Timber and Glazing Specifications

Industry Timber Species and Glazing Units for Period Doors and Windows

Timber Species advised and offered by Sashpro for your project will depend on the general usage and demand. It is also advisable to consider geographical aspect in order to ensure longevity.

A prerequisite is that the wood we use is properly sourced using FSC certification as well as cut, dried and stored in a manner that will provide for superb joinery.

All supplied timbers are from FSC certified farmed sources from the UK, europe, USA and Africa and our joinery is available in the following species: european redwoods (pinus) ; douglas fir ; sycamore ; cedar ; larch ; oak ; willow. All sill works for either windows or doors are made from Iroko or Sapele which are suited to footfall use.

Other names:- none
Uses: Everything exterior.
Sashpro’s explanation: To be honest a bit of an overkill as it has built many a fine bridge, also prone to heavy marking as it reacts to all but the highest quality steel which isn’t always available in ironmongery! This very special timber is produced by way of a process that engages farmed and abundant redwoods (pine) and pressure treats it (acetylation) with raw vinegar. This seals the capillaries within the timber to produce probably the most stable and ecologically famed timber in the world. Commonly referred to as the Teak of the 20th century.


Douglas Fir

Douglas Fir:
Other names:- British Columbian Pine (Uk); Oregon Pine (USA)
Note: Not a true pine.
Uses: Exterior and interior joinery as well as a plethora of industrial applications.
Sashpro’s explanation: Most of the UK’s conurbation’s windows were made from a species called “Pitch Pine” and other redwoods.  With similar properties, douglas fir lacks the problematic exuding of resin and is generally knot free. It should last in service 100+ years. It also has exceptional insulating qualities and a U Value of .2 (when dried to a 14% -approx-moisture content).  As acrylic paints that are more environmentally friendly and last longer intact, this species takes readily to them. There is little movement in service and this species is suitable for doors, sash and casement windows.


Other names:- Gold Coast Cedar; Penkwa
Uses: Used in the solid for doors (though not in panel joinery due to its propensity to ‘move’) and exterior joinery as well as a plethora of industrial applications.
Sashpro’s explanation: Not to be confused with Mahogany this slow growing though abundant African species is best used in the construction of windows for sill works or ‘short standard’ joinery as it does move in service unless braced.


Other names:- mvulu; odum
Uses: Boat building; interior and exterior joinery, furniture making and carvery.
Sashpro’s explanation: A very stable timber species readily available today with huge stability and minimal movement in service. Great for period timber doors and sill works.



OakEuropean Oak:
Other names:- Quercus Robur
Uses: Used for exterior joinery such as windows and doors only in reasonably sheltered conditions.
Sashpro’s explanation: Because of numerous inquiries of this species we thought it prudent to add it here. However due to its propensity to season very slowly and as it does so to crack and warp it is best used for fine furniture.


Much touted ‘engineered’ timbers are great for strength but lack the qualities of sheer endurance as the glue that binds them deteriorates over time. We feel you should know a that engineered timbers, just as chipboard, is a cheap way of getting to a finished product. We only use wood in its solid and natural form.

High Performance State-of-the-Art Glazing for all our Windows and Doors

Sealed Unit

There’s really only one type of glazing that complies with both Building Regs and is purpose-made for period style glazing to timber sash and casements windows, main entrance and garden or external utility doors. Ultra slim sealed units made with Warm Edge technology means that ambient temperatures do not travel across from the external pane to the internal pane that comprise a double glazed sealed unit (DGU).  Inert gas has since the inception of sealed units been Argon.  Because slim sealed units offer an inherently lower volume of gas a far more dense gas is now widely used called Krypton and in some cases, Xenon. When these elements are combined with high performance glass such as Pilkington’s KA or Planitherm Total + from St Gobain which are both LowE ( low emissivity) we get discreet high performance with Building Regulations environmental policies met and exceeded. The glass aspect of the sealed units can also be toughened or even provided in a toughened laminate for a virtually impact proof set-up.

Pilkington’s Whispa glass can be combined into a DGU and provide calculated sound-proofing from properties that face busy roadways or overflight noise.

Where period windows and doors must improve insulation properties dramatically while keeping traditional looks intact these products have created a quiet revolution. In an ever increasing noise filled environment you’ll also be amazed at how much ambient noise is reduced when employing state of the art double glazed sealed units into traditional timber windows and doors.