Interior Window Trim

{{Infobox
|title = Interior Window Trim
|image        = [[File:Space holder.jpg|215px|alt=Block Glass Windows]]
|header5 = Interior Window Trim
|data6 =  Interior Window Trim for Replacement Windows
|header7 = Description:
|data8   = Interior window trim adds an attractive appendage to replacement window applications.

The addition of interior window trim can add character and individuality to replacement windows. The trim is often one of the main components of the window which creates the desired architectural elements that windows offer. 

== Interior Window Casings ==
Window casing are an aspect of a window's design that adds an attractive depth, detail and richness to a room, creating the room's finished look. These trim elements cover seams and hardware by utilizing any of numerous profiles, sizes and materials. Interior trim can enliven a room by its positioning, color, design or material. It often serves as a transitional component which allows the window style to successfully blend in with the home's overall pattern and appearance. 

=== Window Trim Elements ===
There are a number of constituent elements of window trim including moldings, base, window rails, wainscot and casings.

==== Base ====
The base trims a large window along the floorboard where a large window, such as a bay or bow window, and floor come together. The base, also referred to as the "baseboard" or, in the UK, a "skirt," conceals any openings that exist between the floor and window finishes and protects the window from splashed water as well as from swinging feet, furniture scratches, etc. Traditionally, bases were designed using three separate parts: the baseboard (a tall, flat piece), the cap (an ornamental piece that sits on top of the baseboard) and the shoe (the small, beveled or curved piece that transitions from baseboard to floor).  Homeowners who want to create an authentic period look may prefer to install a traditional window base. Bases can also be constructed from one piece for a cheaper, cleaner and more contemporary appearance which are often used when buildling more modern room applications. 

==== Chair Rail ====
The chair rail is generally installed up to about 36 inches from the floor next to a window but can also be installed up to the top of the window. The chair rail's aim is to protect the wall finish next to a low window from bangs and bumps that can result from furniture which is placed next to the window. To that end the chair rail splits the wall into horizontal layers. 
Windows which might require a chair rail include floor-to-ceiling [[bay windows|bay]] and [[bow windows|bow]] windows.

==== Wainscot ====
The area between a chair rail and baseboard is often paneled, called the "wainscot." Wainscot may include beadboard, wood panels, raised panels or horizontal wood paneling. Wainscot is a window trim option for floor-to-ceiling windows such as bay or bow windows. 

==== Casing ====
Replacement windows may be framed by window casings which include four separate pieces -- two on either side of the window, a top piece and a bottom piece. These pieces can be matching or may be distinct from one another which enables the homeowner to plan the casings as specifically detailed pieces. Each piece of casing may be purchased, milled and installed separately to provide the homeowner with the exact profile that he prefers. One option may include placing a horizontal band along the top of a window which will provide the base for a shaped crown.  

==== Window Sills ====
A window sill is an attractive and functional part of any window style.  Window sills, also called "stools," extend along the bottom edge of a window to present a protruding lip, also called a "horn." These sills may include either narrow or deep horns and can be shaped according to any architectural design. The horn can end at the outer edge of the window casing or be extended for a style variation. Window sills allow homeowners to increase the appearance of a replacement window by placing decorative items along the window ledge. A horizontal "apron" can be attached to sill from underneath for an added design enhancement. 

==== Picture Rail ====
The picture rail trims a window at the top of the window, near the ceiling. This trim piece is generally used as a decorative element which divides the wall into horizontal layers.

==== Plate Rail ====
A plate rail is often seen framing the top of a window in homes with traditional architectural designs including Colonials, Cape Cods and Ranch styles. The plate rail serves as a platform that allows the homeowner to display decorative objects above the window. Depths of plate rails can range from shallow rails to deep rails. The depth of the rail will determine its location, with deeper rails, used for larger decorative objects, requiring a higher placement so that the rail remains out of the way. A display of plates, for example, necessitates a thin rail which allows full view of the plates and will not disturb the flow of the room if it is installed in a low location.  

===== Trim Line =====
A trim line is a variation of the plate rail. It adds interest to the space above a window. Trim lines placed above a window and below the ceiling are powerful design tools. In addition to making a space more interesting and rich, this trim line may be used as a base for an outdoor underhang, or soffit.

==== Corner Blocks ====
Corner blocks are square trim pieces which are placed within the corners of a window's trim. They can be etched or carved with special shapes, often including circular designs or flower shapes but they are sometimes left plain. The inclusion of corner blocks in a window trim eliminates mitered casing corners.  Solid wood crowns can add extra texture to the corner block appearance.  

=== Trim Materials ===
Materials used for window trim can include PVC, fiberboard and wood.

==== Fiberboard Trim ====
Fiberboard is a medium density replacement window interior trim which is relatively inexpensive. It is easy to mill and paint but it is not as durable as wood or PVC and, if not thoroughly primed and painted, can be susceptible to water damage. Environmental activists also voice concerns regarding the dust that fiberboard creates when it is being cut or routed which can cause healthy problems if inhaled. 

==== PVC Interior Trim ====
PVC (polyvinyl chloride) trim is a plastic which resembles wood trim. It is a long-lasting material but requires specific installation techniques for a successful installation. It is formulated to be resistant to sunlight and maintains its paint without chipping, peeling or fading. PVC trim doesn't rot or warp because it doesn't absorb water. Many installers prefer to work with PVC which resembles wood. The pricing of PVC trim is comparable to wood trim.

==== Wood Trim ====
Wood window trim is the preferred trim for many replacement window applications due to its appearance which gives the window facade the look of an "authentic" wood window. Homeowners can select an inexpensive wood for an unvarnished window trim such as aspen, poplar or finger jointed wood.  Stained or varnished wood trim can include pine, oak, maple, mahogany or cherry wood.