Inside Mount vs Outside Mount: Choosing the Right Fit for Your Sheridan Windows

Sheridan Window Treatments · 2026-09-22

Nobody grows up knowing the difference between inside mount and outside mount, and there's no reason they should. It's a decision that only matters the day you're ordering window coverings, and by then most Sheridan homeowners have already spent more time picking a color than thinking about how the hardware actually attaches.

Inside Mount and Outside Mount, Defined

Inside mount means the blind or shade sits inside the window frame itself, tucked into the opening so the headrail is basically flush with the trim. From across the room it looks built in, like the window was designed around it. Outside mount means the hardware attaches to the wall or trim in front of the opening, covering the frame rather than fitting inside it.

Neither one is the correct choice in some general sense. They're just two different ways of solving the same problem, and which one works on a given window in Sheridan comes down to measurements more than preference. A window with 2.5 inches of clear depth and nothing in the way can usually take either mount. A window with a crank handle intruding into that space or a sill that slopes toward the glass often can't take inside mount at all.

The visual difference matters too. Inside mount shows a bit of the frame around the edges of the shade, which a lot of people like because it reads as more architectural. Outside mount hides the frame entirely and can make a window look larger, since the headrail extends past the actual glass. Once you've seen both on a real house instead of a showroom display, the difference is obvious.

Why Homeowners Choose Inside Mount

Here's a myth worth clearing up first: inside mount isn't automatically the higher-end option. It's simply the option that keeps trim visible and hardware tucked inside the frame, which a lot of people prefer visually, especially where the trim itself was worth the money.

It also tends to sit better in rooms with limited clearance. A kitchen window with a faucet close to the glass, or a stairwell window where anything protruding into the room becomes a hazard, both favor inside mount because the hardware stays entirely within the opening rather than reaching into the room.

The real tradeoff, and the thing most first-time buyers don't expect, is the light gap along the edges. Because an inside mount shade has to be built slightly smaller than the opening to physically fit inside it, a strip of light sneaks around the sides. It's a minor issue in most rooms and a real one in a bedroom that needs to go fully dark.

Mixing Mounts and Getting a Consistent Look Room to Room

One thing that surprises people: your whole house doesn't need to match. Plenty of Sheridan homes have deep original frames in some rooms and shallower frames in others, and ending up with inside mount in one room and outside mount in another is completely normal, not a sign anything went wrong.

Where consistency actually matters is within sightlines. A kitchen open to a living room will look better if the color and headrail style carry through even if the mount underneath differs, since color and shape catch the eye long before depth does. Within one single room, though, keep the mount consistent across the windows in it. A row of three matching windows on one wall, mounted two different ways, reads as a mistake even when each individual choice was technically correct for that window.

If one window in a row genuinely can't take the same mount as its neighbors, that's worth talking through before ordering. Sometimes a small adjustment, like a slightly different headrail style on just that window, keeps the row looking intentional instead of accidental.

If you're staring at a window trying to guess whether it has the depth for an inside mount, a tape measure only tells you part of the story. A free in-home measure settles it in a few minutes, and you'll walk away knowing exactly which mount your Sheridan windows can actually support before you spend a dime on product.

Depth, Obstructions, and Other Mounting Realities

Whatever the room, the frame's actual depth overrides any preference. Faux wood blinds typically need 2 to 2.5 inches of clear space to sit inside a frame properly. Cellular shades can sometimes work with a bit less. Shutters need the most, generally 3 to 3.5 inches, because the panel frame adds real bulk inside the opening.

Kitchens and bathrooms are the rooms most likely to throw a curveball here, since they're also the rooms most likely to have cranks, locks, or plumbing eating into that depth. A bedroom window is usually simpler by comparison, with fewer obstructions to work around.

Sloped sills deserve their own mention, since they're easy to miss on a casual look. A sill that angles down toward the glass instead of sitting flat can make a blind sit crooked or rub against the glass with every use, even on a frame that measures deep enough on paper.

Why Homeowners Choose Outside Mount

Ask yourself first whether the frame even has the depth for inside mount. If it doesn't, or if a crank handle or lock is sitting where the hardware would need to go, the decision's already made for you and outside mount is the answer regardless of preference.

Beyond that forced case, ask how much light control actually matters in that room. A bedroom that needs to go properly dark benefits from outside mount's ability to fully overlap the frame and close the gaps that inside mount leaves open. A home office or a dining room usually doesn't need that same level of light blocking, which is why outside mount shows up more often in bedrooms than anywhere else in a typical Sheridan house.

Last question: is the frame square? Older homes especially can settle unevenly over the decades, and an out-of-square opening is much easier to work around with outside mount, since the header mounts level above the window regardless of what the frame underneath is doing.

Frequently Asked Questions

Why does my window have a gap around the blind?

That's almost always an inside mount doing exactly what it's supposed to do. The headrail sits inside the frame rather than covering it, so a strip of frame stays visible on the sides and sometimes the top. It's not a defect, it's just how that mount works.

Is outside mount more expensive?

Not because of the mount itself. Outside mount usually needs a slightly wider blind to get full coverage, so the material cost can run a bit higher, but the difference is usually modest rather than dramatic.

What if my window frame is uneven or out of square?

That's a common reason to go with outside mount. It hangs from a straight header above the frame, so a crooked or out-of-square opening underneath it matters a lot less than it would with a blind trying to fit snugly inside the frame itself.