Cornice boards have been a beloved architectural feature for centuries, valued for their decorative flair and ability to make a strong visual statement. As an integral design element in many period-style homes, cornice boards continue to strike a top note when it comes to aesthetics and curb appeal.

An Introduction to Cornice Boards

Cornice boards are molded trim pieces that sit just below the roofline, projecting outwards from the top of exterior walls. Visually, they help delineate the transition between the walls and roof. Constructed from wood or molded composite materials, cornice boards add dimensionality, shadow lines, and visual interest to the roofline.

Architecturally, cornice boards serve both form and function. In addition to being decorative, they help protect walls from water damage by diverting rainwater away from the sides of the building. On homes with little roof overhang, the cornice board’s projection gives additional protection.

Cornice boards have been used since ancient times, originating as decorated moldings on Greek and Roman structures. In America, they became especially popular in the 19th century as hallmarks of Greek Revival, Italianate, Victorian, and other period-style architecture.

Today, cornice boards remain sought-after curb appeal enhancers. They make a statement of traditional charm on new construction homes, historical restorations, and remodeling projects alike.

Benefits of Installing Cornice Boards

Visual Interest and Curb Appeal

The number one reason to install cornice boards is aesthetic appeal. With their three-dimensional moldings and prominent facade placement, cornice boards make a bold stylistic statement. They add rich architectural interest, give rooflines a finished look, and boost curb appeal.

Enhanced Historic Character

For period-style homes, cornice boards are important historical elements that complete the architectural style. Whether craftsman, colonial, Victorian or other, a properly designed cornice board lends authenticity.

Added Dimensionality

Cornice boards create decorative shadow lines underneath, making walls appear to have more depth. This added dimensionality makes homes appear larger and more impressive.

Weather Protection

The overhanging shape of cornice boards deflects rainwater runoff away from walls and windows, protecting siding and trim. They also help shield walls from damage related to freeze-thaw cycles.

Increased Property Value

Eye-catching curb appeal additions like cornice boards can increase a home’s value. In one study by the National Association of Realtors, attractive landscaping and exterior upgrades boosted property values by as much as 15%.

Design Flexibility

Cornice boards come in a wide array of sizes, shapes, and styles. Ranging from simple to ornate, they offer great flexibility in complementing any home’s architecture and design sensibilities.

Common Styles of Cornice Boards

Cornice boards come in a variety of designs to match different architectural styles:


Featuring clean, simple lines, Craftsman-style cornices have a subtle overhang and expose visible rafter tails. They often incorporate brackets beneath the eaves.

Colonial Revival

Colonial cornice boards have a boxed design with decorative crown molding and dentil details. Their style ranges from simple to highly ornate.


Italianate cornices have a deep, bold overhang with large, highly detailed curved brackets underneath. Their ornamentation creates a dramatic look.


Victorian cornice boards involve elaborate wooden scrollwork. They feature decorative end brackets, pendants, and intricate designs like spindles, shapes or half-rounds.


Unfussy, minimal ornamentation defines farmhouse cornice boards. Usually made of wood, their simple overhanging shape mimics pragmatic rural architecture.


With clean lines or unique angular shapes, modern cornice board styles make a contemporary design statement. They forgo highly decorative details.

Design Considerations for Cornice Boards

Several factors go into designing well-proportioned, stylistically appropriate cornice boards. Key considerations include:

  • Roof type – Consider the roof shape. For example, gabled roofs suit triangular cornice boards while hip roofs pair better with rectangular cornices.
  • Architectural style – Match the cornice board style to the home’s architecture. Seek designs that align with the aesthetic, ornamentation, and period details.
  • Scale and proportions – Cornice boards should be sized in proportion to the home’s scale. Typically, larger homes suit bigger cornices while smaller dwellings require more modestly scaled trim.
  • Materials – Wood, fiber cement, and composite materials like urethane and PVC are common. Consider exterior grade, durability, and maintenance needs.
  • Ornamentation – Decide how simple or ornate the trim details should be. Factor in the home’s other decorative elements for cohesive styling.
  • Color – Choose a color that complements the roof, exterior color scheme, and architectural style.
  • Budget – Cornice board costs range widely depending on materials, size, and detailing. Generally, simpler is more budget friendly.

Popular Materials for Cornice Boards

Cornice boards can be constructed from solid wood, engineered wood or composites. Choosing a durable, low-maintenance material suitable for exterior installation is key.


  • Cedar – Naturally decay-resistant softwood that’s lightweight and easy to cut. Needs periodic sealing and staining.
  • Redwood – Beautiful wood that’s naturally insect-resistant. Requires some ongoing maintenance.
  • Pine – Affordable softwood. Must be properly sealed and painted for exterior durability.

Engineered Wood

  • Hardboard – Made from compressed wood fibers. Dense and smooth. Comes pre-primed and is paintable.
  • MDF – Composite of compressed wood fibers and resin. Smooth finish good for molding detailed shapes.


  • Polyurethane (urethane) – Lightweight, durable, and naturally resistant to moisture and insects. Low maintenance.
  • PVC – Long-lasting, weather-resistant plastic that won’t rot or warp. Comes pre-primed for paint.
  • Fiber cement – Composite of wood fibers and cement material. Withstands weather well. Won’t burn or rot.

Installation Tips for Cornice Boards

Proper installation is key to maximizing the longevity and performance of exterior cornice boards. Here are some best practices to follow:

  • Check local codes for any specific requirements in your area regarding attachments, projection size, and stormwater drainage considerations.
  • Ensure the mounting surface is smooth, clean, and free of old caulk or debris. Repair any damaged wall areas.
  • Use the manufacturer’s recommended installation methods and corrosion-resistant fasteners. Most attach with screws driven into a solid structural framework.
  • Seal and prime boards prior to installation. Use high quality exterior-grade primer and paint.
  • Install flashing above cornice boards to direct water into gutters and protect the home from moisture damage.
  • Caulk seams with flexible, paintable exterior caulk leaving proper gaps for expansion and contraction.
  • Apply a clear protective sealer to wood cornice boards once installed to protect from moisture and UV rays.
  • In climates with frequent freeze-thaw cycles, ensure proper attic ventilation and air sealing to prevent ice dams.

Maintaining and Repairing Existing Cornice Boards

Regular maintenance preserves the beauty and function of existing cornice boards. Recommended care includes:


  • Inspect cornices yearly for damage, deterioration, and age-related defects. Check for cracking, rot, loose fasteners, caulk failures, etc.

Sealing and Painting

  • Reseal, prime and repaint cornice boards as needed to protect from moisture and UV exposure. Expect to do this every 5-7 years typically.
  • Look for peeling paint, fading, and bare wood exposure as signs it’s time to recoat.


  • Make timely repairs to any damaged sections, loose ornamentation, failed caulk, or areas of water infiltration.
  • Replace severely damaged boards. Use an oscillating tool to remove existing boards neatly before installing new replacements boards.

Pest Prevention

  • Keep cornices free of exposed wood tunnels where pests can enter. Cover with hardware cloth if needed.
  • Watch for signs of carpenter bees, termites or woodpecker damage. Treat affected areas promptly.

Design Inspiration: Creative Cornice Board Ideas

Beyond traditional applications, cornice boards can add unique architectural interest in creative ways. Here are some inspiring design ideas:

Indoor Installations

Add cornice boards inside to define room architecture. Picture frame moldings, shelving trim, and faux columns for visual interest.

Complementary Accents

Pair exterior cornice boards with other architectural details like decorative gable vents, brackets, millwork shutters, or garage door trim.

Molding Medley

Layer molding profiles like bed molding, cove molding, or crown molding atop cornice boards for ultra-dimensional lines.

Materials Mix

Combine materials like accenting fiber cement board edges with PVC decorative molding inlays for visual depth.

Lighting Elements

Incorporate lighting to illuminate ornate cornice board details. Picture soffit downlighting or LED rope lights.

Dormer Accents

Use triangular cornice boards on gable dormers for added roofline personality. Paint a complementary dormer color.

Faux Finishes

Fake intricacy with faux wood grain or marbleized painted finishes on ornate composite cornice boards.

Frequently Asked Questions

What size should cornice boards be?

Typical cornice board sizes range from 4-12 inches deep and 4-8 inches tall. Scale the size up for larger homes and down for smaller homes. The projection depth should be about half the height.

How far should they project from the wall?

A general rule of thumb is to allow the cornice to project 2 inches for every 1 foot of wall height. A 10-12 inch projection is common for 8 ft high walls. Adjust to suit the home’s scale.

How are they attached to the home?

Cornice boards usually attach to a ledger board secured to the studs or rafter tails using corrosion-resistant finishing nails and screws. durable exterior adhesives can also adhere boards to surfaces.

What’s the best way to seal and protect them?

Use high quality primer and exterior paint to protect wood and composite cornice boards. Reapply protective finish coats every 5-7 years. Seal raw wood edges before installing.

Should I install gutters above cornice boards?

Yes, installing gutters above the cornice board roof projection is important to direct rainwater into downspouts and protect siding from water damage.


With their dramatic lines and expressive detailing, cornice boards add character, charm, and curb appeal to homes. As distinctive architectural elements, they make a strong stylistic statement and elevate roof aesthetics. From traditional to modern interpretations, cornice boards strike a top note visually, lend historic authenticity, and boost property values. With proper installation and care, they enrich home design for years of enjoyment.