|External doors are made in several standard sizes to meet most domestic needs, and modern homes tend to use standard-size joinery; the Standard Metric being 2000 mm x 807 mm. External doors are produced in two thickness, 40 and 44 millimetres. External doors are usually much heavier than internal doors due to their thickness and material used.
In The beginning
Unhappy with animal skins draped over entrance ways, our ancestors looked to a better material for filling the gap, something more substantial. Timber seemed an ideal choice considering that it grew everywhere in abundance as well as being a workable material. However, there was a problem as the only practical way to cover an area such as a door opening in those days was by binding small tree trunks or branches together.
As things progressed, trees were cut into uniform pieces such as planks, which, when put together formed a flat surface. Collectively, these planks formed a timber structure which could be made wide enough to be used as a door. By binding or dowelling horizontal cross pieces known as 'ledges' onto them, proved a good way of joining them all together, as well as providing rigidity at the same time. Though this method may have been adequate, it was not ideal, because to produce a substantial door would mean thick timbers, making it extremely heavy, not to mention looking unsightly.
This principle design of a door proved to be very popular, and with the more recent advancement in production methods meant that the timbers could be machined and planed into very thin, smooth uniform sizes, and the vertical pieces tongued and grooved together rather than the original simple butt joint.
This is the simplest form of a door and was still widely used in houses and cottages up to the 1920/30. As for today, Ledged and Battened doors would only be used for narrow openings where the appearance is not important, such as sheds, gates and various outbuildings.
When used as doors for the home or outbuildings, the vertical tongue & groove boards have the edges chamfered so as to produce what is known as 'matchboarding'. Chamfering the edges of the boards produces a 'V' shape when the two edges are brought together, which makes a feature of an otherwise unattractive joint and serves to hide unsightly gaps that appear when the timbers shrink. The Ledges are also beveled when used externally, so by preventing water from lodging on them.
Eventually though, a method of producing doors was formulated, where a timber framework was produced in the shape of the door with uniform small openings where thinner timber panels could be introduced. This leap in design was know as the panel door.
It's only by using modern machinery and certain timbers, such as mahogany, that a single solid panel suitable for producing a 'single panel door' can be produced, only possible in a framed construction. However, as a result of modern sheet materials and veneering, this is no longer such a problem and where solid timbers are used for paneling, the wider panels are more likely to be produced by using two or three pieces and carefully jointing them together.