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inspiration · Arched

SW Colonnade Gray Arched Wall Molding

SW Colonnade Gray Arched Wall Molding: wall elevation, color data (LRV 53.1), living room layout for 12, 15, 18 ft walls, cut list, calculator and pre-cut kit

Catalog snapshot View 2 sources ↓

Project calculator

Wall molding linear-foot estimate

Estimate for rectangular molding frames.

Estimated quantity122.28 linear feet

Divide by 7.87 ft (240 cm stick) and round up for the number of sticks.

Formula & assumptionsframe_count * 2 * (frame_width_inches + frame_height_inches) / 12 * (1 + waste_percent / 100)

Assumes identical rectangular frames. The waste allowance is editable. The estimate does not optimize cuts or include separate rails, baseboards, or other trim.

Overview

SW Colonnade Gray is a light gray with a warm (yellow) undertone and a calculated LRV of 53.1. Against white trim the contrast ratio is 1.63:1, which gives soft contrast; painted tone-on-tone, the arched pattern shows only through its shadow lines.

Arched layout on a 15 ft living room wall

Molding over the full wall height, upper and lower rows divided by a chair rail. On a 15 ft wall with an 8 ft ceiling this gives 5 frames per row, each 31.2 in wide, with 50 in upper and 21 in lower frames. The layout uses about 40.43 m of 2.5 cm molding, or 17 sticks of 240 cm, including 10% waste. Center the layout on the sofa or TV rather than the wall when furniture is off-center.

Building the arched pattern

Arched tops are pre-formed in MDF; the straight sides and the bottom rail are cut to the same width as the arch. Fix the arch first, then hang the sides from it.

Painting molding in SW Colonnade Gray

Grays sit in the middle of the contrast range: white trim reads clearly, while same-color trim gives a quiet, architectural look.

Wall elevation

SW Colonnade Gray wall, tone-on-tone trim, arched layout on a 15 ft wall. Colors are screen approximations.

Color data

ColorBrandCodeHexCalculated LRVUndertoneDepthContrast vs white trimContrast vs black trim
SW Colonnade GraySherwin-Williams#C6C0B653.1warm (yellow)light1.63:19.12:1

Trim color pairings

PairingTrim colorHexContrastEffect
tone-on-toneSW Colonnade Gray#C6C0B61:1Trim painted the same color as the wall
matching whiteSW Greek Villa#F0ECE21.53:1White with the closest undertone
contrastBlack#1F1F1F9.12:1Dark trim for a graphic outline

Living Room wall sizes: arched accent wall layout

Wall widthFrames per rowFrame widthFrame height (upper / lower)Molding incl. 10% waste240 cm sticksChair rail pieces (300 cm)
12 ft431 in50 / 21 in32.26 m142
15 ft531.2 in50 / 21 in40.43 m172
18 ft631.3 in50 / 21 in48.6 m212

Cut list for a 15 ft wall

Planning cut list
PieceQuantityLength
Frame top and bottom (lower row)1031.2 in
Frame sides (lower row)1021 in
Arch frame sides (upper row)1034.4 in
Arch top + bottom rail (upper row)531.2 in span
Chair rail2300 cm lengths

Pre-cut kits for this wall

Pre-cut kits that fit this project. Open a kit for photos, options and pricing.

Flexible Arch Trim Wall Molding Kit | Pre-Cut MDF Decorative Wall Panels01 / KIT

Flexible Arch Trim Wall Molding Kit | Pre-Cut MDF Decorative Wall Panels

From $83.40

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Flexible Arched Wall Molding, Paintable MDF Wall Trim, Pre-Cut Arch Decorative Wall Panels | Picture Frame Molding, Accent Wall Trim02 / KIT

Flexible Arched Wall Molding, Paintable MDF Wall Trim, Pre-Cut Arch Decorative Wall Panels | Picture Frame Molding, Accent Wall Trim

From $73.60

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Arched Accent Wall Trim Molding Kit, 3 Widths | Pre-Cut MDF03 / KIT

Arched Accent Wall Trim Molding Kit, 3 Widths | Pre-Cut MDF

From $58.40

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Modern Arched Wall Panel Kit: Pre-Cut MDF Wall Molding04 / KIT

Modern Arched Wall Panel Kit: Pre-Cut MDF Wall Molding

From $140.00

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Half Wall Arched Wainscoting Panels Kit | Pre-Cut MDF Easy Installation05 / KIT

Half Wall Arched Wainscoting Panels Kit | Pre-Cut MDF Easy Installation

From $73.60

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Arched Decorative Wall Molding Panels, 1 to 5 Arches | Pre-Cut MDF06 / KIT

Arched Decorative Wall Molding Panels, 1 to 5 Arches | Pre-Cut MDF

From $146.40

View kit

Questions

How much molding do I need for a 15 ft living room wall with arched frames?

About 40.43 m (133 linear ft) including a chair rail and 10% waste, which is 17 sticks of 240 cm. That assumes 5 frames per row, 31.2 in wide, on an 8 ft ceiling.

Is SW Colonnade Gray warm or cool?

SW Colonnade Gray has a warm (yellow) undertone and reads as a light gray. Its calculated LRV is 53.1, so it sits in the mid range, where molding shadows show clearly.

Should trim be the same color as SW Colonnade Gray walls?

Painting the molding the same color gives a modern, tone-on-tone finish where only shadows show the pattern. White trim adds soft contrast (1.63:1), and black trim gives 9.12:1.

How high should the chair rail be in a living room?

About one third of the ceiling height: 32 in on an 8 ft ceiling, 36 in on 9 ft and 40 in on 10 ft. Center the layout on the sofa or TV rather than the wall when furniture is off-center.

Trace the details

Sources & dates

Prices, options and photos come from our product catalog on the date shown. Layout tables are planning estimates; measure your wall before ordering.

  1. Paint color dataset (screen approximations; LRV calculated)Recorded November 11, 2026
  2. DecoMoldings product catalogRecorded November 11, 2026