Flat Stock Casing – Simple Modern Interior Window Details


Flat stock casing offers simple, modern interior window trim details. This thin square wood piece can be painted the same color as other pieces for a seamless final aesthetic.

As opposed to other forms of trim, flat stock casing doesn’t necessitate miters or unique routed surfaces – making it a cost-effective choice for homeowners.


Flat stock trim is an affordable and flexible choice for modern interior window details, ideal for creating stylish yet sophisticated window details. This type of trim can also be combined with decorative elements to achieve a fashionable and refined aesthetic, along with drywall returns, jamb extensions, and reveals. Additionally, this type of trim can also be utilized with cabinetry designs to achieve an overall cohesive aesthetic.

Flat casing stands out from its counterparts as being straightforward and unadorned with miters or unique routed surfaces, making it suitable for shelving, window ledges, and wainscoting applications. Available both in MDF and hardwood in 1xs, 5/4xs, or 2xs sizes, it can easily be cut with a saw or jigsaw for easy installation and can even paint well when machined quickly – an excellent choice indeed for shelving, window ledges, and wainscoting projects!

One of the most widely used uses for flat stock trim is to frame windows. This technique provides an elegant or art deco aesthetic and works with any casing profile; choose a color that complements the overall aesthetic of the room and use matching window and base trim pieces for an eye-catching effect. Furthermore, consider base cap molding for added decorative detail!


Flat stock trim can make a big, impactful statement in any home without breaking the bank. Available in different sizes and styles to meet any design need, this type of molding is much simpler to work with than its more complex counterparts, such as casings – make sure you consider all options before selecting your preferred style.

Flat casing trim can be used in various projects, from shelving baseboards and window/door casings to window ledges and shelving ledges. Not only is this affordable trim great at concealing seams and adding unique design touches, but it is also versatile enough to pair with other types of frames for a truly personalized look.

Flat trim strips make an excellent finishing touch when installing a coffered ceiling or intricate paneling in modern homes, offering a subtle aesthetic without overpowering the eye with too many patterns or colors.

Flat casing makes drywall returns easy; this fuss-free window trim option removes the need for complicated reveal techniques and reduces finish carpentry costs. Coordinating interior trim details with other design aspects is vital for creating an appealing visual aesthetic in a home.

One of the most accessible and most affordable ways to upgrade a basic flat casing installation is pairing it with a base cap molding, such as one featuring an attractive profile like that found on plain matte stock, to add visual interest and depth to a finished installation. This combination is often referred to as “Speed Base,” making installation simple enough even for an inexperienced trim carpenter.

Easy to work with

Flat stock trim is an essential interior molding used to frame windows, doors, ledges, and other architectural features such as windows or doors. Also referred to as S4S (Surfaced 4 Sides), it can be combined with base cap molding to form more decorative profiles that can be utilized in coffered wall designs as well as intricate paneling patterns.

Though you can create custom window trim designs with flat stock, professionals advise coordinating framing details with base trim and interior door casing designs for an integrated look throughout the home. Combining different molding styles is an excellent way to achieve unique looks without incurring unnecessary expenses or inconvenience from purchasing custom pieces.

The flat casing’s most attractive quality lies in its subtlety; it doesn’t hog all of the attention in a room yet still adds charm with other trims and decorations, such as corbels or lintels, to add character and depth to it.

The flat casing can also be used to make elegant floating shelves. Simply encasing a plain frame with a flat case makes an eye-catching architectural feature in any room, especially if painted a vibrant hue for its shelf and flat container – use either matching shades or dare to go bold with contrast!


Flat stock trim molding adds character and dimension to the simple door and window casings and serves as a complement to more significant enhancements. It’s an affordable choice for wainscoting and other decorative home improvement projects, with numerous styles and sizes to complement any aesthetic. Painting it to match existing trim can create more dramatic effects; moreover, its simplicity means fewer miters or milling!

Flat trim profiles feature 90-degree corners and are simple in shape, unlike more complex casing profiles like colonial or sanitary casings. Common uses for flat trim profiles are framing windows and doors as well as shelves or window ledges in the home; baseboard casing may also be called flat trim, and it comes in finishes like pine, oak, maple, and mahogany to resist water damage, and warping. It comes with non-porous urethane finishes to help fight damage caused by moisture while helping prevent warping!

Some trim and molding features may be elaborate and ornate, while others serve more subtle functions. Subtle elements can add charm without cluttering a room with intricate detail – something especially beneficial in homes trying to achieve modern aesthetics.

Window detailing should never be overlooked when considering design for interior windows and must work in harmony with other aspects of a room’s decor to establish an effective overall space design. From flat trim, drywall returns, jamb extensions, or reveals to flat trim or jamb extensions all these details work to develop a clear logical process within any given room’s layout and should all work to provide a coherent visual aesthetic that unifies all areas within it.