Window Shutters Glossary

New to plantation shutters? Whether you're measuring up for the first time or just want to understand the terminology before you order, this glossary explains everything you need to know in plain English.

B

Bay Window

A window that projects outward from the main wall of a building, typically made up of three or more sections at angles to each other. Bay window shutters require each section to be measured and ordered individually.

Blade

Another term for a louver or slat, the horizontal adjustable strips that run across a shutter panel.

C

Café Shutters

A shutter style that covers only the bottom portion of a window, leaving the top open. Great for street-facing windows where you want privacy at ground level while keeping natural light coming in from above. See our café shutters.

Center Tilt Rod

A vertical rod that runs down the centre of a shutter panel, used to adjust the angle of the louvers simultaneously. A traditional and classic look.

Clearance

The small gap left between the shutter frame and the window recess to allow for easy opening and closing. A standard deduction is usually applied during manufacturing to account for this.

Clearview Tilt Rod

A discreet vertical rod located on the back of the shutter panel, on either the left or right side. It lets you adjust all the louvers at the same time.

Compound Angle

The angle at which shutter panels meet in a bay or angled window situation. Getting compound angles right is essential for a neat, flush fit.

D

Deduction

A small amount subtracted from your submitted measurements during manufacturing to ensure the shutters fit comfortably within the window recess. For inside mounted orders, a standard 1/8" deduction is applied to both width and height.

Dividing Rail

A horizontal rail used to divide shutter panels into sections. For Full Height shutters this refers to a midrail, which may be optional or mandatory depending on the height – This adds extra support and allows you to operate the top and bottom louvers independently, giving you greater control over light, privacy, and visibility. For Tier-on-Tier / Double Hung shutters this refers to the horizontal T-Bar (sometimes called a horizontal T-Post) - a fixed horizontal divider within the shutter frame that separates the upper and lower panels.

DIY Shutters

Shutters that are supplied ready to install by the customer, rather than being fitted by a professional installer. The Shutter Store specializes in DIY plantation shutters, which come with full instructions, frames, and all necessary hardware.

F

Faux Wood Shutters

Shutters made from synthetic materials such as PVC or composite, designed to mimic the look of real wood. A good option for high-humidity environments such as bathrooms. See our faux wood shutters.

Fixed Louver

A louver that cannot be adjusted or tilted — permanently set at a fixed angle. Common in solid or decorative shutters. We do not offer this type of shutter or louver.

Frame

The surround into which shutter panels are fitted. The Shutter Store supplies a custom-built frame with every order, cut to your exact window dimensions.

Full Height Shutters

Shutters that cover the entire height of a window from top to bottom in a single configuration. The most popular shutter style. See our full height shutters.

H

Hardwood Shutters

Shutters made from real timber such as Paulownia, Basswood, Poplar, or Ash. Hardwood shutters offer a premium finish and excellent durability. See our wood shutters.

Hidden Tilt Rod

A mechanism that allows louvers to be adjusted without a visible rod running down the centre of the panel. Creates a cleaner, more contemporary look. Sometimes called a rear tilt or invisible tilt.

Hinge

The hardware that connects shutter panels to the frame, allowing them to swing open. The Shutter Store offers a choice of hinge colours to complement your interior.

I

Inside Mount (IM)

A fitting method where the shutter frame sits inside the window recess. Gives a clean, built-in look. Requires sufficient recess depth for the frame to sit flush.

J

Jamb

The vertical sides of a window frame or recess. When measuring for inside mount shutters, you measure between the jambs to get your width.

L

Louver

The individual horizontal slats that make up the main body of a shutter panel. Louvers can be tilted to control light and privacy. Available in different widths — typically 2½", 3, 3½", 4, or 4½" at The Shutter Store.

Louver Size

The width of each individual slat. Larger louvers (e.g. 4½") allow more light in when open and offer a more contemporary look. Smaller louvers (e.g. 2½") give a more traditional appearance and more precise light control.

M

Midrail

A horizontal dividing bar across the middle of a Ful Height shutter panel to provide structural support. The position of the midrail can sometimes be specified at order stage. Depending on the height of the shutter it may be mandatory or optional.

Mullion

A vertical dividing strip between two shutter panels within the same frame. Also known as a vertical T-Post. Sometimes used for decorative effect or structural support on wider windows.

O

Outside Mount

A fitting method where the shutter frame is mounted on the wall surrounding the window recess, rather than inside it. Useful when there is insufficient recess depth for an inside mount, or to make a window appear larger.

P

Panel

A single shutter unit containing louvers within a frame. A window may have one or multiple panels depending on its width.

Paulownia

A lightweight, sustainable hardwood commonly used in shutter manufacturing. Fast-growing and eco-friendly, it offers excellent strength relative to its weight. Used in our Luxe Wood range.

Plantation Shutters

Interior window shutters with wide, adjustable louvers. The style is one of the most popular window coverings in the US. See all plantation shutter styles.

Polyvinyl (PVC) Shutters

Shutters manufactured from a rigid PVC compound, making them fully waterproof and ideal for bathrooms, kitchens, and other humid environments.

Poplar

A sustainable hardwood prized for its excellent strength-to-weight ratio. Lightweight yet durable, poplar offers a stable, smooth surface that takes paint beautifully for a crisp, long-lasting finish. Used in our American Wood range.

R

Rail

The horizontal frame members at the top, bottom, and middle of a shutter panel. Top rail, bottom rail, and midrail.

Recess

The window opening or reveal into which shutters are fitted when using an inside mount.

Reveal

See Recess. The depth and dimensions of the window opening are critical measurements when ordering inside mount shutters.

S

Slat See Louver

The terms slat, louver, and blade are all used interchangeably.

Solid Raised Shutters

Shutters with solid panels rather than adjustable louvers. Offer maximum privacy and a distinctive raised panel appearance. See our solid raised shutters.

Split Rail

When a horizontal rail is positioned at a specific height to divide a shutter panel into upper and lower sections. Commonly used on tier-on-tier shutters to align with the window sash or locking mechanism. Also known as a horizontal T-Bar or dividing rail.

Stile

The vertical side members of a shutter panel frame. Along with the rails, stiles form the outer border of each panel.

T

Tier on Tier Shutters

A shutter style where the top and bottom halves of the window are covered by independent panels that can be opened separately. Ideal for windows where you want maximum flexibility over light and privacy. Also known as Double-hung shutters.

Tilt Rod

The push rod or mechanism used to adjust the angle of the louvers. Available as a Center tilt rod (traditional, visible), Clearview tilt rod (Discreet, placed on the back), or Hidden tilt rod (contemporary, concealed). See also: Center Tilt Rod, Hidden Tilt Rod.

V

VOC (Volatile Organic Compounds)

Chemicals found in some paints and finishes that can off-gas into the air. The Shutter Store uses low-VOC finishes on its painted shutter ranges, making them safer for your home environment.

W

Warp

A bend or twist in a shutter component that occurs due to changes in humidity or temperature. Quality hardwoods and proper installation help minimise warping. Manufacturing tolerance levels at The Shutter Store allow for no more than 1/16" of warp per 12".

Waterproof Shutters

Shutters made from materials that can withstand moisture and humidity without warping, swelling, or discolouring. Ideal for bathrooms and kitchens. See our waterproof shutters.

Window Recess

See Recess.

Z

Z Frame

A specific frame profile used on some of The Shutter Store's American ranges for face fitting (Face Mount). When ordering with a Z frame, a mandatory 1/4" deduction is applied to your submitted measurements.

Still have questions?

Our team of shutter experts is here to help. Call us on 888-753-8290, visit our FAQs page, or contact us and we'll be happy to talk you through anything.