Glossary of wooden door terms

About Wooden Doors - Glossary of Terms -

When looking at or reading about doors, you are likely to come across some new and old terminology, this list may help.

Here is a list of the words and phrases often used when describing wooden doors or parts thereof.

If there is something you need to know about and which isn’t in this list we apologise and ask you to contact us directly.


ARCHITRAVE or FACING; The decorative moulding that surrounds the door and bridges the gap between the edge of the door frame and the wall.

APERTURE; The term used for an opening either in a door where glass would be fitted or a hole in the wall into which a frame and a door would be fitted.

ASSESSMENT REPORT; This usually relates to a fire door. Each fire door has its own assessment report, issued by a fire testing authority which outlines how a fire door should be installed.

Reports for fire tests are available on request.

BEADING; The mouldings that surround a panel in a solid door or a pane of glass in a door.

CASINGS or FRAMES; A common word referring to an internal door frame. Formed from one piece of material whose edge has been machined to form a rebate into which the door will close? (see rebate and linings)

CERTIFIRE; An audited system within the door industry to which the (JB Kind) Royale and Illusion ranges are registered.

The Certifire scheme provides an independent audited process to ensure the Fire Doors are manufactured to specific standards.

It is similar in principle to the Gas Safe registration scheme for gas fitters and gives you the assurance that your (JB Kind) Fire Door has been approved for the purpose.     

CONSTRUCTION; Door Construction is the term used to describe the composition of a door. Usually prefixed with words such as ‘solid’, ‘engineered’, ‘block timber’ or ‘composite’ etc

ENGINEERED OR COMPOSITE CONSTRUCTION; This term signifies that an assortment of component materials have been combined to produce the finished article rather than a single plank or piece of wood as might have been the case in times past.

A Composite construction gives doors more strength and stability, whilst allowing them to look “solid” through the use of a real timber veneer. Materials used in composite construction include chipboard, MDF, blockboard, LVL (Laminated Veneered Lumber) and flaxboard.

CORE; The inner fabric of the door, usually describing the material within the visible components. A range of core materials are used in JB Kind doors, e.g. The Royale range has a high density chipboard core.

The (JB Kind) River Oak range has a block timber core within its framing and an MDF core within its panels.

Pine doors have a blockboard core made of pine. (Except knotty pine which are regular solid pieces)

CORNER BLOCKS; A decorative item which can form a junction between the vertical leg section of an architrave and the horizontal head section of architrave at the top.

DOOR FURNITURE; Another term for door handles and knobs. Also known as ironmongery.

DOOR SKIN; A preformed sheet which may be flat or moulded, to form a panel shape. The door skin is bonded to a core or fitted to a lattice framework of timber to form the complete door.

DOWELLED JOINTS; A form of joint between two components, giving stability to the door structure.

FINISH; When we refer to our “door finishes” we are talking about the veneer or visible surface of the door.

Some of our doors are supplied with the terms “Finished” or “Pre-finished”, usually with a clear lacquer, or UNFINISHED/NATURAL where you are able to apply your own finish to achieve the effect you require.

Please note that all doors must ultimately be finished to comply with our warranty.

FIRE DOORS; These are doors which have been tested to conform to prevailing standards, aimed at preventing the spread of fire. Many of our ranges include Fire Doors, usually specified at 30 minutes (FD30) which means that they are able to resist the passage of fire for more than 30 minutes.

We also sell doors within our door blank ranges rated to FD60 (60 minutes). Fire doors must be fitted correctly, using appropriate glazing, door frames and ironmongery.

See also 'Intumescent strips' below.

FLAT PANEL; A panel on a door which is not raised, bevelled or profiled.

FRAMES; The timber component that is fitted within a wall opening to which a door is fitted. Externally known as frame, internally see 'casing' and 'linings'.

GASKETS; Most common for use as glazing gasket used around the perimeter of fire glass within our (JB Kind) Royal and Illusion ranges. May also be used to describe weather seals within external door frames.

GLASS/GLAZING BEAD; The moulding used to fix pieces of glass in position within a door.

GLAZING BAR or ASTRAGAL; A solid piece of timber that separates individual panes in a multiple pane door.

HANDING; Most commonly for door pairs, to describe which leaf of a pair opens first.

This is important to us when we are rebating doors for our customer.

Doors are handed on the basis of left or right hand being pushed away first. Visualise yourself standing in front of the doors and decide which you would PUSH away first.

Handing is often abbreviated to RHA (right hand away) or LHA (left hand away). Look also for the abbreviation which indicates that the doors should be rebated RMS (Rebated Meeting Styles)

HANGING STILE or HINGE SIDE; of the door which the hinges must be fitted and then fitted to the frame.

HARDWOOD/SOFTWOOD; In general terms hardwood comes from trees that are deciduous and lose their leaves (e.g. Oak). Softwood comes from trees that are coniferous and have needles (e.g. Pine).

There are a few exceptions to this rule but none that relate to timbers within our range.

Hardwoods are generally slower growing which results in tighter grain structures, making them denser (and therefore heavier) than softwood. In general, hardwoods have more structural appeal and a harder wearing, although this isn’t always the case, for example balsa wood is structurally very weak but is classified as a hardwood.

HIGH DENSITY CHIPBOARD; A manmade timber product manufactured when wood chips and resin are mixed together and pressed into sheets. Lighter in weight than MDF but is very stable and is ideal for use as a door core or substrate.

Although moisture resistant versions are available, we only offer these cores for internal use within our (JB Kind) Royale and Illusion ranges.

HOLLOW CORE; Usually used to describe the internal construction of cheaper internal doors where there is a presence of fresh air. Hollow core doors are not strictly speaking empty inside, they may have a cellular core (or egg box) made of cardboard and with the appearance of honeycomb.

INTUMESCENT SEAL OR STRIP; All dedicated fire doors providing a half hour or greater performance will be fitted with intumescent seals which expand when hot, to seal the gaps between the door leaf and the frame and at the meeting stiles of pairs of doors.

JB Kind Fire Doors use a material called PALUSOL, which is sheathed in plastic and inserted within a groove machined into the edge of the door or the frame rebate.

The size of the material varies according to the individual door. More information is usually available from the door’s assessment report.

LAMINATE or VENEER; Many of J.B. Kind’s doors use a sheet of timber that is bonded to a core, to create a variety of high quality door finishes.

Plastic laminates are now commonly found in flooring and furniture and often have a realistic timber appearance.

LEADING STILE; When fitted into a door frame, the Leading Style (or edge) is the one opposite to the hinges (i.e. it “leads into the room” when the door is opened.

LIGHT or LITE; This refers to an individual pane of glass within a door. E.g. a “2 light” door has 2 panes of glass.

LININGS or FRAMES; This is the internal part of a door frame, which the door fits inside.

The lining is combined with a stop which is fixed within the lining to form a rebate into which the door closes.

LIPPINGS or FOREDGES; Lippings, usually made from solid timber, are used to create a solid door edge, enabling the door to be planed to reduce their size to fit a specific door opening, without exposing the inner core of the door.

The solid lipping also allows the edges of the doors to be rebated to form pairs.

MDF, Medium Density Fibreboard; This is a manufactured wood product made of wood fibre and resins which is then pressed out into sheets of varying thickness.

MDF is very stable and versatile, ideal for use as a substrate or door core, underneath the timber veneer.

MDF is used within the panels of the internal Opera and River Oak ranges.

MEETING STILES or MEETING RAILS; The edges of two doors where they meet as a pair. May be described as square meeting stiles (SMS) or rebated meeting stiles (RMS)

MORTICE AND TENON JOINT; A common type of joint used in external doors as an alternative to a dowelled joint.

MOULDING; A shaped profiled piece of timber that may be used around the perimeter of a panel or a piece of glass.

It may also be attached to the face of a flush door to create an individual pattern.

MUNTIN; A vertical component usually used in a 4 or 6 panel door, to separate 2 individual panels. It is usually positioned in the centre of a door that has an even number of panels.

OPENING or APERTURE; A hole in a wall into which a frame is positioned (BRICKWORK OPENING) or the opening within a frame into which the door is positioned (FINISHED OPENING).

PANES; Usually refers to pieces of glass. (See lights)    

PILASTER or “T” PIECE; A means of forming a rebate within a pair of doors without machining the edges of the doors.

The pilaster is a separate timber moulding that is fixed to the edge of one leaf to form the rebate.

May also be called a T-bar.    

PLINTH BLOCK; A rectangular piece of timber, sometimes decorated, to form the junction between the bottom edge of an architrave leg and an adjacent skirting board.

RAILS or STILES; The components forming the horizontal framework of a panelled door, e.g. Top rail, Midrail, Bottom rail.

REBATING/REBATE; Rebating is the process of machining a groove into the edge of a piece of timber. In the case of doors, the edges of two doors may be rebated to form a pair with rebated meeting stiles (RMS). Door frames also have rebates into which the door closes.

JB Kind often use the term RMS when referring to door pairs.

Many of our door ranges (e.g. Royale, Opera, Illusion and Village) have sufficient depth of timber within the lipping to enable sufficient trimming to create a rebate without exposing the core or the door, so that 2 single doors can be rebated to form a pair. We offer rebating as an additional service.

When rebating doors into a pair, 12mm of timber is removed from the edge of each meeting stile, to create a partial overlap where the doors meet.

STILES or RAILS; Similar component to a rail but in the vertical plane at the side of the door.

Specific terms are hanging stile, leading stile and meeting stile.

SUBSTRATE; Material used to fabricate the core. E.g. High density chipboard, MDF, etc.

TEMPERED/TOUGHENED SAFETY GLASS; To comply with UK building regulations all glass supplied in (JB Kind) doors is safety glass.

Safety glass is heat treated so that, should it break, it becomes granular and does not create sharp shards (like a broken bottle).

Glass marking is now a legal requirement and all of our glazing is permanently marked to show its compliance with regulations for the benefit of building control officials.

VENEER; A thin slice of timber used as a decorative material on the visible faces of many of our doors.

WEATHERBOARDS or WEATHER BARS; A timber moulding that should be fitted to the bottom edge of the external face of an external door, to deflect water away from the bottom edge of the door.

See below our pdf of this "Glossary of Terms" for wooden doors.

Printable Version

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