Accurate measuring is the first step to blinds that fit, function and look right. Whether you are ordering for a single window or an entire home, the method you use depends on one core decision: will the blind sit inside the window recess or on the wall surrounding it?
This guide covers both approaches in plain steps, so you can record the correct dimensions before placing a custom order.
| Factor | Inside Mount | Outside Mount |
|---|---|---|
| Appearance | Flush, built-in, trim stays visible | Larger visual presence, covers frame |
| Frame depth needed | Yes, minimum recess depth required | No recess needed |
| Light gap at edges | Narrow, limited by frame width | Reduced by overlap on each side |
| Best for | Deep, square frames; minimalist interiors | Shallow frames, obstructions, wider coverage |
| Forgiving of uneven frames | Less forgiving | More forgiving |
| Typical overlap added to width | None (uses exact recess width) | 50 to 100 mm each side |
Use this table as a starting reference when deciding which mount type suits each window before you begin measuring.
Always record measurements in millimetres. All made-to-measure blinds are manufactured to the millimetre, and a difference of even 5 mm can affect how a blind sits in or around a frame.
Inside mount blinds fit entirely within the window recess. When raised they remain inside the opening. This style suits deeper frames and gives a clean, architectural finish that preserves any existing trim or architraves.
Before submitting your order, measure the depth of the recess from the glass surface to the front edge of the frame. This figure must meet or exceed the minimum depth specified for your chosen blind type. A headrail that protrudes beyond the frame will obstruct opening and closing. If the recess is too shallow, an outside mount is the practical alternative.
Inside mounts are a common choice in Melbourne and coastal homes where trim detail is a considered part of the interior, and where a minimal, integrated look is preferred.
Outside mount blinds fix to the wall, ceiling, or architrave above and around the window frame. They cover the full window opening and extend beyond it, which reduces light gaps and is more forgiving of frames that are shallow, uneven, or obstructed by hardware.
Outside mounts are widely used in Queensland and regional NSW homes where wall space is available and maximum coverage is a priority. They are also the practical choice when window handles, latches, or uneven sills make an inside mount impractical.
When comparing mounting hardware options for this approach, reviewing roller blind mounting brackets will help you confirm which bracket type suits your wall material and fixing position.
The right choice usually comes down to three factors: available recess depth, frame squareness, and the level of light control you need.
Consistent habits across all windows reduce errors on large orders. The following checklist applies to both mount types.
Before you measure
While you measure
When you record
For a broader walkthrough of measuring principles across different blind types, the guide on how to measure for blinds covers additional scenarios useful before placing a multi-window order.
Blinds Deal supplies made-to-measure blinds across Australia, with delivery available to every state. All products are manufactured to your submitted dimensions, which removes the need for on-site trimming or adjustment. The range covers both inside and outside mount styles across a variety of materials suited to different climates, including Queensland humidity and cooler Victorian interiors.
The measuring guide provides additional reference for homeowners and tradespeople preparing custom orders.
Measure the width at the top, middle and bottom and the height at the left, centre and right. For an inside mount, use the smallest width and the largest height. If the frame is noticeably out of square, an outside mount is more forgiving because it overlaps the frame rather than fitting within it.
Yes. Inside mount blinds need enough recess depth, measured from the glass to the front of the frame, to hold the headrail without protruding. Check the minimum depth listed for your chosen blind type before ordering. Shallow frames may suit an outside mount instead.
For made-to-measure blinds you generally submit the exact recess or wall measurements and the manufacturer applies any factory deductions. Confirm whether the retailer expects exact opening sizes or finished blind sizes before submitting, so no double deduction is made.
No. The mount type determines the dimensions the blind is manufactured to. An inside mount blind is cut to fit within a recess; an outside mount blind is wider to overlap the frame. Confirm your mount type before placing the order.
Outside mounts can reduce light gaps at the sides because the blind extends beyond the window frame on both sides. The extent of that improvement depends on how much overlap you add. Inside mounts sit within the frame, so some light can enter at the edges if the frame is not perfectly flush with the blind.
