Technical Specs
Inside vs Outside Mount - Which Roller Shade Mount and Why
October 31, 2026 · By Rolli Shades
6 min read
6 min read
Inside mount or outside mount for roller shades: the 2 in depth rule, light gap, how each measures, what Rolli deducts at the factory, and which to choose for bedrooms, trim, shallow frames and tile.
Guide · Measuring and fit
Inside or outside mount? Check the depth, then the light.
An inside mount sits within the window frame and shows the trim; an outside mount covers the frame and blocks more light at the edges. The frame decides first: Rolli needs at least 2 in of flat depth from the glass or any crank to the front of the frame for an inside mount. After that, the room decides.
2 inMinimum frame depth, inside mount
3 + 3Width and height measurements
1/8 inMeasure to
0Deductions you make; Rolli deducts at the factory
1–2 inOverlap per side, outside mount
Comparison
Inside and outside, side by side
| Inside mount | Outside mount | |
|---|---|---|
| Where it sits | Inside the window frame | On the trim or the wall above the frame |
| Look | Built-in; trim stays visible | Covers the frame; reads as a soft panel on the wall |
| Light at the edges | A small gap each side, because the fabric runs narrower than the headrail | Least light: fabric overlaps the opening by 1–2 in per side |
| Frame depth needed | At least 2 in from glass or crank to the front of the frame | About 2 in of flat surface for the bracket face; depth does not matter |
| What you measure | Width in three places (use the narrowest), height in three (use the longest), to 1/8 in; Rolli deducts for clearance | The exact finished size you want, including overlap and where it should stop (sill, apron or a line matched to the room) |
| Obstructions | Cranks, locks and alarm sensors must sit behind the 2 in line | Crown molding, vents and sensors must leave 2 in of flat surface |
| Surfaces | Wood frames easiest; vinyl and metal need the right fasteners | Wood trim easiest; drywall needs anchors; tile and stone need masonry fasteners |
| Rolli recommends for | Kitchens, offices, living rooms with good trim; any room where the view of the frame matters | Bedrooms, media rooms, nurseries, shallow or crooked frames, windows with handles in the way |
The light gap
Why inside mounts show light
The motor or clutch sits inside the tube, so the fabric is narrower than the headrail. On a Rollease Acmeda Zero Li-ion motor the head hides in the tube, giving the smallest gap in its class, but no inside-mount roller is zero-gap. For a bedroom that must be dark, Rolli recommends an outside mount with 1 to 2 in of overlap, or an inside mount with a blackout layer behind, or side channels.
What this means for your home
Measure the depth first. Under 2 in and the decision is made for you: outside mount.
Bedroom and media room: outside mount, blackout fabric, 1 to 2 in overlap per side. Living room with trim you like: inside mount, and accept the small gap.
Mixed rooms can mix mounts. Rolli matches the fabric and bottom bar so an inside-mount kitchen shade and an outside-mount bedroom shade read as one set.
Next step
Measure in five minutes
Questions
Mounting, answered
How much depth do I need for an inside mount?
At least 2 in from the glass, or from the nearest crank or lock, to the front edge of the frame, so the brackets fit fully inside. Less than that, choose an outside mount.
Do I subtract anything for an inside mount?
No. Give Rolli the narrowest of three width measurements and the longest of three heights, to 1/8 in. Rolli makes the clearance deduction at the factory.
Will an inside mount block all the light?
No. The fabric runs narrower than the headrail, so a small gap shows on each side. For full darkness use an outside mount with overlap, a dual roller with a blackout layer behind, or side channels.
Can I mount on tile or vinyl?
Yes, with the right fastener: masonry anchors for tile and stone, self-tapping screws for metal, care with vinyl frames. Note the surface for each window when you measure; Rolli packs the hardware to match.
Which mount for motorized shades?
Either. Motorized shades need the same 2 in depth inside the frame. The charging port sits at the headrail end on the side you choose, so leave it reachable.
Sources
- Rolli: how to measure for roller shades — 2 in depth rule, three-measurement method, factory deduction, overlap
- Rollease Acmeda Zero motor launch release — smallest light gap claim
Vendor figures restated from published documents; Rolli prices are the live configurator prices on rollishades.com as of 31 Oct 2026 and change without notice. Automate® and ARC™ are marks of Rollease Acmeda.
Measured, made and installed by Rolli
Motorize it once, properly.
A designer confirms the motor, tube and control for every window during the free consultation. Shades ship in 3 to 10 days.
