How to Hang Curtains on an Arched Window: The 3 Install Strategies and the 6-Step Process

Done right, an arched window frames a room. Done wrong, the panel drops flat at the springline and the arch looks like a decorating mistake for the next ten years. The strategy you pick in step 1 rules out the wrong path before you touch a drill, which is why most first-time installs go sideways: the rod gets bought before the strategy gets chosen.

The three viable approaches are a straight rod above the arch, a bendable rod that follows the curve, or a two-part treatment with a sunburst insert covering the arch and operable panels below. Step 1 alone decides which one belongs in your room. For the wider context on arch, half-round, palladian, and skylight coverage, the arched and specialty window hub sits one click away.

The 3 Install Strategies at a Glance

Most owners default to strategy 1 whether they know it or not, because it works and the hardware costs $30. Strategy 2 is where purists live and where budgets stretch. Strategy 3 shows up in rentals and in high-end colonial builds where the arch is already dressed with a permanent decorative insert.

This guide covers all three, but the 6-step process below assumes strategy 1 (the recommended default). Step 5 branches into strategy 2 for anyone committed to the bendable route.

The 6-Step Install at a Glance

The full arch install runs 35 to 50 minutes per window once tools are on the ladder. Read the sequence first, then work each step in order.

Step 1: Choose Between a Straight Rod, a Flexible Rod, or a Two-Part Treatment

Straight Rod Above the Arch (Recommended for 90%)

The straight rod above the arch is the default for a reason: it ignores the curve entirely, opens the arch itself for uninterrupted daylight above the panels, and works with any standard rod, any bracket, and any panel header. Per The Spruce arched window curtain reference, this is also the approach most professional designers recommend for arches under 60 inches wide.

Where it fails: arches over 60 inches wide sitting in rooms with 8-foot ceilings can look cramped, because the rod eats visual headroom that the arch was designed to give. In that case, either mount the rod higher and accept a longer panel drop, or step to strategy 2. If it were my kitchen arch, I would default to strategy 1 and stop overthinking it.

Flexible / Bendable Rod That Follows the Curve

Real talk on bendable rods: they cost 3 to 5 times a standard rod, they only work with clip rings or ring-and-hook combos, and they need a cardboard arch template shaped on the floor before you mount them. Two Pages does not carry bendable rod hardware; Kirsch, Umbra Cappa Curve, and custom aluminum-bent rods from workroom suppliers are the market. The panel disappears behind the arch curve when open, which is the reason to pick this path.

Common failure modes: bought before measuring the flex radius, formed too sharply so the rings jam at the peak, or paired with pinch pleat or grommet headers that physically cannot navigate the bend. If your arch is a full half-round with a tight radius under 20 inches, ring glide gets sticky on cheaper bendable rods within the first year.

Two-Part: Fan or Sunburst Insert + Panels Below

The two-part approach dresses the arch permanently with a fixed pleated fan or sunburst insert, then hangs standard operable panels on a straight rod at the springline. This is the traditional colonial and Federal-style solution and it works for palladian windows where the arch is a distinct upper element separated by a keystone or mullion. The arch stays dressed year-round without moving, and the panels below operate normally. Sunburst inserts are custom-made, non-operable, and sourced from workroom shops rather than mainstream retailers.

Step 2: Measure the Arch (Peak, Springline, and Drop)

Peak height above the frame

Measure from the top of the window trim to the highest point of the arch curve. This number tells you where the rod cannot go: never below 4 inches above the peak, or the panel clips the curve when open. Typical residential arches add 8 to 18 inches of peak height above the springline; palladians can add 24 to 36 inches.

Springline width

The springline is the horizontal line where the arch curve meets the vertical side walls of the window. This defines your panel width baseline. For coverage, add 6 to 12 inches per side past the springline, so a 48-inch springline width means a total rod span of 60 to 72 inches.

Total drop from bracket to floor

Measure from the planned bracket location (4 to 10 inches above the arch peak) down to the floor, then subtract 0.5 to 1 inch for float clearance. For puddled panels, add 1 to 3 inches instead. Custom drops on Two Pages panels go up to 130 inches, which covers most residential arches sitting on 9 or 10 foot ceilings.

Step 3: Mark the Bracket Position and Wall Type

Set bracket marks 4 to 10 inches above the arch peak, spanning 6 to 12 inches past each springline. For 8-foot ceilings, keep the rod closer to 4 inches above the peak. For 9 or 10 foot ceilings, push to 6 or 8 inches, or split the difference between peak and ceiling.

Run a stud finder along the marked line. Studs almost never land above an arch peak because the framing sits around the window opening, not above it. Plan on toggle anchors from the outset. Identify the wall surface before you drill: drywall, plaster, or brick each carry different anchor rules.

Drywall vs plaster vs brick

Standard 1/2-inch drywall takes toggle bolts and Snaptoggle metal anchors reliably. Pre-1950 plaster over wood lath is fragile: drilling too aggressively cracks the plaster face, and anchors spin unless you find the lath behind. Brick or masonry needs a masonry bit and sleeve anchors, per the This Old House drywall anchor guide. If your home dates from before 1950 and the walls have never been drilled above the arch, do a test hole in a hidden spot first.

Wall type	Recommended anchor	Pilot bit	Weight rating
1/2 in drywall (hollow)	Snaptoggle metal or 1/4 in toggle bolt	1/2 in	25 to 50 lb per anchor
5/8 in drywall (hollow)	Snaptoggle metal or 3/16 in molly	1/2 in	30 to 60 lb per anchor
Plaster over wood lath (pre-1950)	Wood screw into lath, or molly with careful pilot	1/8 in pilot, drilled slowly	15 to 25 lb per anchor
Brick or masonry	Sleeve anchor or plastic wall plug	1/4 in masonry bit	40 to 80 lb per anchor
Wood trim or header	#8 wood screw direct, no anchor	3/32 in pilot	50 lb and up

Step 4: Install the Brackets Level and Balanced

Screw the brackets into the anchors following the fundamentals from any standard curtain rod install guide: bracket flush to the wall, screw fully seated, level checked across both endpoints before final tightening. For arched windows, the extra step is checking that both brackets sit at exactly the same height, because any drift becomes visible when the panel drops past the arch curve.

Bracket spacing for arch coverage

For a 48-inch springline, brackets sit at 54 to 60 inches apart center-to-center. For a 72-inch springline, brackets sit at 84 to 96 inches apart. The extra 6 to 12 inches per side lets the panel stack back cleanly when open and covers the springline transition when closed.

Center support for wide arches

Arches wider than 60 inches at the springline need a center support bracket directly above the peak. Without it, the rod bows down over the peak within 3 to 6 months and the panel starts sagging at the middle. For arches over 96 inches wide, use two center supports evenly spaced.

Step 5: Attach the Rod (Straight or Bent)

Standard straight rod

Thread the rings, hooks, or grommets onto the rod on a flat surface before lifting it into place. Then drop the assembled rod into the bracket cradles and tighten the set screws or seat the finials. This sequence takes 5 minutes and prevents the common error of sliding a loaded panel over an already-mounted rod, which pulls brackets out of the anchor over time.

Bendable rod technique

Cut a piece of cardboard to the arch profile using a marker traced against the trim. Lay the bendable rod on the cardboard and shape it to the curve, working from center outward with slow steady pressure. Test-fit against the actual arch before mounting: cheap bendable rods spring back 5 to 10% once released, and clip rings need to glide across the peak without catching. Mount the formed rod to the bracket cradles and clip the panel rings on.

Step 6: Hang the Panels and Dress the Folds

Header choice for arch coverage

Pinch pleat reads cleanest with a straight rod above the arch: the pleat structure holds a consistent fold from ring to floor, which makes the panel look intentional against the exposed arch curve above. Ring or clip headers are required for bendable rods. Grommet headers work on straight rods but the inner diameter needs to match rod diameter within 1/8 inch, or the grommet catches during draw.

The 12-inch overhang finish

Panels should extend 6 to 12 inches past each springline to give clean stack-back, and puddle 0.5 to 1 inch on the floor for formal spaces or float 0.5 inch above the floor for casual and high-traffic areas. For Two Pages panels, the Liz Linen Drape Pleated at 350 gsm and 90/10 poly-linen blend is the flagship for arches because the pleat structure holds a defined fold from the peak all the way down. Configure width and drop against your springline math on the Liz Linen Drape Pleated product page. Adding the linen a final rod tap once the panels are seated aligns the folds and removes any twist.

Pro Tips: 5 Things Owners Wish They’d Known

Five corrections that separate a first-time install from a designer job. Read all five before the panel goes up.

5 Common Mistakes That Ruin the Look

The single most common mistake is the one this guide starts with: buying hardware before choosing the strategy. Here are the other four.

Now You’ve Hung Them: Configure the Panel for the Drop

The rod is level, the brackets are anchored, and the strategy is settled. The remaining variable is the panel itself, and on an arched window the drop math matters more than any other spec. A rod placed 8 inches above the peak adds 8 inches to the visible drop, and short panels are the single most preventable install error.

Two Pages custom panels ship at your exact width and drop, so the bracket-to-floor number you took in step 2 goes straight into the configurator. For arches with heavier daylight loads, add a cotton or blackout lining at checkout. Apply code JULY for 20% off and the panels are on a 10 to 12 day timeline.

FAQ

Can you put a curtain rod on an arched window?

Yes, and the three viable approaches are: a straight rod above the arch peak (recommended for 90% of installs), a bendable rod that follows the curve (custom bent, purist look), or a two-part treatment with a sunburst insert covering the arch and operable panels below the springline. Straight rod above is the cheapest, fastest, and works with any panel header. Bendable rod is the aesthetically purest but costs 3 to 5 times as much and works only with clip rings.

How high above an arched window should you hang curtains?

Mount the rod 4 to 10 inches above the peak of the arch. Four inches is the minimum for the panel to fully clear the peak curve. On 9-foot ceilings, push to 6 or 8 inches. On 10-foot or vaulted ceilings, mount halfway between the peak and the ceiling, or 4 inches below the crown molding if there is one. Mounting flush with the arch peak is what makes the window look squat and defeats the visual gain of having an arch in the first place.

What kind of rod do you use for an arched window?

For strategy 1 (straight rod above), any standard 5/8 or 1-inch diameter rod works. For strategy 2 (following the curve), you need a bendable curtain rod such as the Kirsch flex rod or a custom-bent aluminum rod matched to your arch template. Bendable rods work only with clip rings or ring and hook combos, never with grommet or pinch pleat headers directly. For strategy 3 (two-part), a standard rod hung at springline level pairs with a permanent arch insert above.

How do you cover just the arch part of a window?

Use a sunburst or fan-style insert, which is a fixed pleated fabric arrangement radiating from the base of the arch to the peak. These are typically custom-made to the arch dimensions and are non-operable. Two Pages does not carry sunburst inserts. Alternatives include a decorative window film for the arch portion only, a stationary shirred panel tacked to a curved rod, or leaving the arch bare and dressing the rectangular section below.

How wide should curtains be on an arched window?

Panels should extend 6 to 12 inches past the springline on each side. Springline is the point where the arch curve meets the vertical side of the window. This gives enough width to stack back cleanly when open and cover the springline transition when closed. For a 48-inch-wide arched window (measured at the widest point of the arch), plan for a total panel width of 60 to 72 inches, split across two panels.

Can you use a tension rod for an arched window?

Yes, but only for strategy 1 (straight rod above the arch) and only for narrow arches under 48 inches wide, with light sheer panels. Tension rods do not follow curves and cannot support the weight of blackout or heavy velvet panels reliably over an arch install. For anything wider or heavier than a sheer, a mounted rod with brackets is required. Tension rods are the correct call for rental scenarios where drilling above the arch is not permitted.

Do you hang curtains from the arch or from the ceiling?

For most arched windows, hang from a bracket 4 to 10 inches above the arch peak, not from the ceiling. Ceiling-mounted curtains are only correct when the arch peak sits within 4 inches of the ceiling itself, or when you want a floor-to-ceiling drama effect regardless of the window shape. Ceiling mount hides the arch entirely, which usually defeats the reason for having one. Arch-above bracket mount frames the arch while giving the panel space to clear the peak.