Window Shutter Glossary

Quite often when discussing internal louvre doors or external, decorative shutters terms or phrases are used which may not be used in everyday conversation. Here’s our glossary of terms which we hope will help if you have crossed by a word or phrase you’ve not heard before: 

A

Acclimatisation 

Wood is a natural material and as such is vulnerable to cold, heat and moisture that causes contraction and expansion that follows the wood grain.  To acclimatise any timber product, it should be left in the room or area that it is to be installed in for at least 24 hours prior to installation. If acclimatisation is not followed, then the timber could expand or contract after installation creating unforeseen problems.

Aperture (Reveal)

is the opening that houses the door or window frame.

B

Battens

If you hear the phrase battens when talking about louvre doors it will usually refer to using a small piece of wood or a ‘batten’ to reduce the size of the doorway /opening to be able to fit a smaller size door into that opening.

Biscuit joint

This is a small, thin oval shaped of wood that is used to attach one piece of timber to another to create a butt joint. Each component will have a routed slot and a ‘biscuit’ shaped piece of wood is used to join the pieces together and is glued into place. The glue makes the ‘biscuit’ swell so the joint becomes tight and secure. It is a similar process to using dowels but uses discs and slots instead of holes and round pegs/ dowels. Biscuit jointing is generally much stronger than dowel joints as there is more surface contact with the biscuit.

Bracket

A type of fixing to mount decorative (nonfunctional) shutters to the wall. There are many different types of bracket available. 

Butt joint

A butt joint is when two pieces of material are joined together end to end without any shaping taking place (i.e sanding down to create a curve).  Butt joints can be held together with many different materials such as glue, dowels or biscuit joints. 

C

Carcass

The body of the shutter.

Cathedral Top

This refers to the scalloped, arched bottom edge of the top rail of a shutter. This is an alternative style to straight top shutters. 

Colour Matched Screw

Colour matched screws are a type of fixing used with external, decorative shutters. They are standard 2 ½ inch steel screws with the heads painted to match your shutters. 

Component part

A component part refers to a piece/part of a larger whole. So for example an external shutter is comprised of various components parts assembled together to create a finished shutter. 

D

Dowel

A dowel is a small cylinder shaped piece of wood that is used to hold together two sections of timber i.e. the rail to the stile. Holes are drilled in each piece of timber for the dowel to be inserted and glued to half its length in one hole. It is then inserted and glued into the hole in the section it is being attached to. The edges of the two sections are glued and clamped together. When the glue dries the dowel adds considerable strength to an otherwise weak joint. Longer dowels are called dowel rods which can be cut into smaller dowels called dowel pins.  

E

Engineered Stile

Where the stile of a louvre door is built from thin strips of wood that are bonded together with one strip of wood having the grain facing down and the next strip having the grain facing up and so on. This is called an opposing grain that counteracts the natural expansion or contraction of the timber when exposed to heat or cold. The stile is then covered in a veneer to give the appearance of a solid wood. Engineered stiles are higher quality than solid wood equivalents as they are less likely to bow, split or warp. 

Espagnolette

Espagnolette bars have a central handle that rotates to simultaneously send two long bolts into the top and bottom of the window reveal.

F

Ferrule

A Ferrule is a tube with a flanged lip that can be used to support a shutter at it fixing point. It sits behind the shutter and is fixed into place by inserting a long screw through a pre-drilled hole in the shutter and through the Ferrule into the wall. 

Frame (in shutters) 

Not to be confused with the frame of the shutter even though the same word is used. This is the outer frame of a shutter assembly that sits within the reveal that shutters are hinged to. A frame is used to ‘square’ off a window reveal that is unlikely to be square where the shutters are to be installed within the reveal. Not all applications require a frame to house the shutters and are most commonly found on interior shutter installations.

H

Hardware

When we are discussing hardware in relation to louvre doors and shutters we are usually referring to hinges or handles or any other item used in conjunction with a door or shutter (latches, locking bolts etc.). With decorative shutters the hardware is usually faux and used to give the appearance of functioning hardware.

Hinge (in shutters)

The bit that actually fastens onto the shutter to allow it to swing on the pintel.

Hinge (in doors)

Is a type of hardware used to attach a door to a frame to enable it to move (open and close). Depending on the size of the door and frame you may be required to use multiple hinges.

Holdback

Also known as a tie back or shutter dog (USA). Holdbacks keep the shutters to the wall when the shutters are in the open position and stops the shutters from blowing about in the wind. These can take many forms but they all do the same job.

Hollow Box Construction 

Imagine a box but with the rear face removed so you could place your hand in it. Our decorative, external Polypropylene shutters are built from component parts and assembled in a way that has a hollow back. Hollow box construction refers to this design.

L

Lintel

The underside of the top of the window opening. When measuring for decorative shutters the lintel is where you would begin your measurement to obtain the height of the shutter required. 

Louvre (Also known as louver/slat/blade)

A louvre blade is a thin narrow piece of wood (for example) that is spaced apart from adjoining louvre blades to create a gap to allow airflow and some light to pass between each blade. Also referred to as slats, these are commonly found in shutter, blind and door styles. The louvre style is made when louvre blades are placed horizontally across a frame and overlapping each other in an angled, fixed position. A small gap is generally left between each slat to achieve an ‘open louvre’ design. Louvred styles that have no gaps are called faux louvre or closed louvre. It is worth mentioning that louvres are not exclusively angled and can be positioned vertically.  Louvre blades can be made from various materials such as metals, plastic and composite.  

M

Marbella shutter

A Marbella shutter is a type of shutter that was prominent during the 60’s and 70’s. It was made from a plastic called ABS and was created by moulding a single piece of ABS into the shape of a louvre style shutter. There were no gaps between each louvre blade meaning it was a ‘closed’ louvre design. Manufacture of this shutter was discontinued and as a consequence it is no longer available to purchase.

Mortise and Tenon Joint

A mortise and tenon joint is when two pieces of wood are connected together usually at a right angle. One piece of wood will have a rectangular hole routed into it called the mortise with the other piece of wood being jointed having the ‘tenon’. The tenon is a protruding piece of timber that has been cut away from the other section of wood so that it fits into the square hole. The two components are then glued and joined together to make the strongest of joints.    

Mouse-hole 

The small slot with a curved edge that has been cut into the rail to accommodate the tilt rod when the louvres are in the closed position. Again this is usually seen in interior shutters. 

Mullion 

A mullion is another name given to the horizontal bar added to external, decorative shutters. Positioning of the bar can differ per design but is usually centrally placed. 

O

Offset Horizontal Bar

The top and bottom horizontal parts of louvre doors are referred to as rails. Taller louvre doors require extra stability and so for added strength an additional rail is added to the door. Sometimes referred to as mid-rail and generally positioned centrally, it is also commonly positioned off centre. We refer to this as an offset horizontal bar. 

P

Panel

The name given to a solid style of shutter (not louvred).This can also be the name given to a single leaf or wing.

Piano Hinge

A long hinge running vertically up the stile that allows another shutter leaf to be connected to it to make a bi-folding shutter.

Pilot hole

A pilot hole is a small hole drilled into a piece material (i.e. wood) as a guide to ensure the hole has been placed in the correct location and to minimise the risk of the wood splitting / cracking when using screws or needing to make a larger hole.  

Pintel

An ‘L’ shaped fixing into the wall that accommodates the hinges that are mounted on the shutters. The long leg of the ‘L’ fixes into the wall with the short leg sticking vertically upright.

Pintel Plate

Does the same job as the pintel except that this is mounted onto a backing plate that is then fixed to the wall.

Primed

A primed louvre door is a door that has an applied base coat of paint to aid adhesion making it ready for a top coat of paint to be applied.  When painting bare timber and after applying the primer/ base coat, it is generally good practice to apply an undercoat to mask any imperfections in the timber itself. Some louvre doors are factory painted white where the paint finish is so good sometimes a top coat is not always required. 

Profile

The shape of the material (when viewed end on) used to make any particular part of the shutter itself or shutter frame.

R

Rail

The horizontal part of the frame that makes the top and bottom of a shutter or louvre door. The entire outer frame of a door will have a top and bottom rail and stiles either side (we discuss stiles next).  Not to be confused with a door frame that is the frame surrounding the doorway opening

Rebated edge (in louvre doors)

A rebated edge is a small groove cut out of a piece of wood allowing it to be fitted against another piece of wood that has had the opposite groove removed (left and right edges) so that they fit and lock together.  

Rebate (Rabbit-USA) (in shutters)

A rebated edge can be given to shutter wings to allow them to lock together or close against each other when closed over the window. Rebated edges will need to be the reverse of each other to be effective i.e. left and right handed rebates.

Recess

The depth that the window is set back from the edge of the facing brickwork.

Reveal

This is the hole in the wall that accommodates the window or door frame.

Routed

Routing is done by using a rotating spinning blade to create slots or grooves in the timber frame. Routing is usually done to create joints between stiles and rails or to house the louvre blades.  

S

S Hook

A type of holdback made in an ‘S’ shape. The S has uneven curves and rotates around a pintel so that it always settles in the upright position. To free the shutters from behind it, the S hook is rotated into a horizontal position that allows the shutter to pass.

Shutter Spike

Shutters Spikes are a type of fixing for external decorative shutters. This is their sole purpose. They are made from a plastic called Polypropylene and have a button head finish and a serrated shank. They are available in various different colours and cannot be painted. 

Shutter stop

A small block that allows a shutter to stop in a given position usually mounted on the windowsill or under the lintel.

Slide bolt 

A bolt that locks the two shutters together. Slide bolts differ from ordinary bolts as they are of a flat rather than circular design.

Strap Hinge 

A long hinge that fixes onto the rail as well as the stile for added strength.

Stile

The stiles are the vertical parts / sides of the frame of a louvre door or shutter frame. On louvre doors the stiles are routed with slots to allow louvre blades to be held in position. Stile construction can vary with simple lengths of solid wood or engineered stiles being the most common methods used (an engineered stile is described further along this glossary). 

Synthetic wood

Is a blend of synthetic polymers that replicates the weight, feel and appearance of wood but does not have any wood elements. This material was developed by Simply Shutters and so the only place you are able to purchase this material is from Simply Shutters in the Town & Country Synthetic range. 

T

Tilt rod

The bar that connects to the louvre blades to allow rapid positioning, opening or closing of all the louvres simultaneously. This feature is predominantly found on interior shutters. 

Track

Where the reveal is very wide or the shutters are too heavy to be hinged, a track is used to support the weight of the shutters. This can be mounted above or below the shutters or both.

W

Weatherproofing

Weatherproofing is the process of making something (i.e an object such as an external shutter) resistant to weather conditions. For example using a specialised external wood paint for an external wooden shutter with the aim to keep it protected from weather conditions. 

Wings

Also known as leafs or panels. Shutters can be made from any number of wings that hinge together. Bi-fold shutters have 4 wings (2×2) whereas tri-fold have 6 wings (2×3).