Arched Wall Molding Layout for a 12 ft Wall

This is a measured arched molding layout for a 12 ft (366 cm) wide wall with a standard 8 ft (244 cm) ceiling. Four arches give a gallery look in living rooms and long dining rooms.

Answer: on a 12 ft wall use 4 arched frames, each 2' 4.5" (72 cm) wide and 6' 2" (188 cm) tall to the top of the arch, spaced 6" (15 cm) apart.

Cut list

Piece	Qty	Length each
Arch side	8	5' (152 cm)
Arch bottom	4	2' 4.5" (72 cm)
Arch top (flexible)	4	3' 9" (114 cm)

Total: 64 linear ft (19.6 m). Order about 71 linear ft (+10% for offcuts).

Why this layout works

Four arches at 28.5 inches keep the semicircle tops generous (14.25 inch radius) while leaving even 6 inch gaps. Three arches on 12 ft would each be over 40 inches wide and lose the slim, tall look.

Time and materials

This layout has 16 pieces. With pre-cut pieces expect about 1 h 50 min to install. Flexible arch tops bend into place without cutting.

How to install

Mark each arch centre line and the spring point 5' above the bottom rail.
Fix the straight sides and bottom of every arch.
Bend and glue the flexible tops.
Caulk and paint.

Questions about this wall size

How many arches fit on a 12 ft wall?

Four arches, each 28.5 inches wide with 6 inch gaps.

Can I put shelves or lights inside the arches?

Yes. Arches over a desk or console often get a small picture light at the top, or floating shelves inside the frame.

Do arches work with a TV wall?

Use 3 arches with a wider centre arch around the TV, or keep 4 equal arches and mount the TV across the centre two.

Get it pre-cut

Arched Decorative Wall Molding Panels, 1 to 5 Arches, from $146
Half Wall Arched Wainscoting Panels Kit, from $74
Flexible Arch Trim Wall Molding Kit, from $83

Shop all arched wall molding kits · Plan your wall free