Measuring guide
Everything we make is cut to the numbers you give us, so those numbers matter more than anything else you'll choose. It takes about ten minutes per window and there is nothing difficult in it — a steel tape, a pen, and the discipline to write down what you actually measured.
Video to come
The full walkthrough — one window, measured start to finish, about 2 minutes.
assets/images/measuring/video/how-to-measure.mp4Two minutes now saves a remake later. Prefer to read? Everything in the video is written out below.
The whole guide in three lines
01 · Preparation
Five habits separate a measurement we can cut from one we have to query. None of them cost you time; skipping them can cost a remake.
Photo to come
Flat-lay: steel tape, pencil, notepad on a warm surface. Everything needed, nothing more.
assets/images/measuring/tools.jpgUse a steel tape
A cloth or plastic tailor's tape stretches, and it stretches more the harder you pull. Over a two-metre window that is easily a centimetre of error you will never see.
Work in centimetres
Our order forms take centimetres to one decimal place — 121.4 cm, not 121 cm and not 1214 mm. Read the tape in the unit you will type.
Never deduct anything
Give us the true size of the opening. Every product needs a different clearance and we apply the right one. Take a centimetre off "to be safe" and we take ours off too.
Measure every window
Two windows built the same week are routinely a centimetre apart once plaster and paint are on. Never assume two are the same. Label your notes by room and position.
Width first, always
Write and say width before drop, without exception. A transposed pair is the most common ordering error in this trade, and it is invisible until the parcel is opened.
02 · The first decision
Before you touch the tape, decide where the finished covering will sit. It changes what you measure, so getting this the wrong way round makes every number after it useless. Almost every window can take either.
The covering sits wholly within the window opening, flush with the wall. The tidier, more architectural look, and it leaves the sill clear.
The covering is mounted on the wall and overlaps the opening on every side. It blocks far more light, and it makes a small window read as a larger one.
Video to come
Measuring a recess fit, start to finish — including the three-point method in practice.
assets/images/measuring/video/recess-fit.mp4Video to come
Measuring an exact fit — where to start the overlap and how far down to go.
assets/images/measuring/video/exact-fit.mp4Replacing something that already fits?
There is a shortcut. Measure the existing blind itself, brackets and fittings included, then order at exact fit using those numbers. We make the new one the same size as the old one and you never think about the recess at all. This only works if you were happy with how the old one sat.
03 · Core technique
No window is a perfect rectangle. Plaster bows, frames settle, and the gap at eye level is rarely the gap at the top. So you measure each dimension three times and let the narrowest one win — because a covering sized to the widest point will jam at the narrowest.
Video to come
Close-up of the tape at all six points, and the diagonal squareness check.
assets/images/measuring/video/three-point-method.mp4Across the top, the middle and the bottom of the opening. Write all three down — don't just remember the one that looked right. Use the smallest.
Down the left, the centre and the right, from the very top of the opening to the sill. Again, all three get written down and the smallest wins.
Run the tape corner to corner, one diagonal then the other, and compare. Differ by 1.2 cm or less and the recess is square enough to fit inside. Any more and a rigid product shows a visible wedge of daylight down one edge — go exact fit instead.
This one check catches more unfittable windows than everything else on this page combined. It takes fifteen seconds.
Enter the two smallest figures, tell us which fit you chose, and stop there. Every allowance the product needs is applied by us against the specification you selected — the slat width, the bracket, the stack, the hem.
04 · Product by product
The three-point method applies to all four. These are the differences that catch people out — read the one you are ordering.
Photo to come
A curtain pole being measured between the finials — the tape clearly on the pole, not the window.
assets/images/measuring/product-curtains.jpgThe exception to everything above: you measure the track or pole, not the window.
Start a curtain →Photo to come
A Roman blind half raised so the folded stack at the top is clearly visible.
assets/images/measuring/product-roman-blind.jpgFabric that folds up into a stack. That stack sits over the window even when fully raised — the thing people forget to plan for.
Start a Roman blind →Photo to come
Close-up of a roller bracket at the top of a recess — showing why the top width is the one that matters.
assets/images/measuring/product-roller-blind.jpgThe tightest tolerance of anything we make — the tube and its brackets must clear the recess at one specific height.
Start a roller blind →Photo to come
A wooden blind in a deep recess, slats tilted — showing how much depth the headrail and slats take.
assets/images/measuring/product-wooden-blind.jpgThe heaviest and deepest product here. Slat width drives both the recess depth you need and how tall the stack sits.
Start a wooden blind →05 · Clearance
Fitting inside the recess only works if it is deep enough to swallow the whole mechanism. Measure from the face of the glass out to the front edge of the wall. If you fall short, the answer is not a smaller blind — it is exact fit, mounted on the wall.
Figures below are provisional. These are standard trade clearances, not yet confirmed against Oro's own hardware. If your recess is within a centimetre of the depth shown, message us before ordering and we will check it against the exact bracket for your specification.
| Product | Flush fit needs | Notes |
|---|---|---|
| Roller blind — top fix | 5.0 cm | Brackets screw into the top of the recess. |
| Roman blind | 5.0 cm | Add depth if the raised stack should sit fully clear of the glass. |
| Wooden blind — 25 mm slat | 5.5 cm | The shallowest slat we offer; the usual answer for a tight recess. |
| Roller blind — face fix | 7.0 cm | Brackets screw into the side walls, so the tube sits further forward. |
| Wooden blind — 50 mm slat | 7.0 cm | The most-ordered width. Needs room to tilt without striking the frame. |
| Wooden blind — 63 mm slat | 8.0 cm | Widest slat, deepest stack. Best on large windows in deep reveals. |
Curtains are absent on purpose — they hang from a pole in front of the window, so recess depth never applies.
06 · Awkward cases
Names for window types vary by region and by builder, so match the picture, not the word. If yours looks like one of these, read that entry before you measure. If it looks like one of these and it's an expensive room, book a consultation and let us measure it.
Photo to come
A bay window shot square-on, so all three faces and both corner angles are visible.
assets/images/measuring/window-bay.jpgWhat it is: A run of windows in a wall that juts out from the room, meeting at corners rather than lying flat. Usually three faces, sometimes five.
Treat every face as its own window, with its own width and drop — never one measurement across the whole bay. Blinds meet at the internal corners, so label which face each number belongs to and tell us whether the corners are square or angled. Curtains need a track that bends; a straight pole cannot follow a bay.
Photo to come
A kitchen or bathroom window with tiles running part-way up the reveal, narrowing it visibly.
assets/images/measuring/window-tiled-recess.jpgWhat it is: A window where tiles run up the inside walls of the opening, usually to splashback height. Common over kitchen sinks and in bathrooms.
The gap between the tiles is almost always the narrowest point in the recess, and the point a blind will catch on. Measure between the tiles as well as at the top. For roller blinds specifically, read the rule above — it is the one product where the top measurement can still be the right answer.
Photo to come
A window handle turned fully open, protruding into the recess — with a tape showing the clearance.
assets/images/measuring/window-handle.jpgWhat it is: Any handle, latch or stay that sticks out into the opening. What matters is where it sits when the window is open, not closed.
Open the window fully before you measure — that is the position the blind has to clear. You want at least 2.5 cm between the blind and any protruding handle. Less than that, and the honest fix is exact fit, mounted forward of the obstruction.
Photo to come
A radiator directly under a window sill, with a curtain hanging beside it for scale.
assets/images/measuring/window-radiator.jpgWhat it is: A heater fixed to the wall directly under the window, so anything full-length would hang in front of it.
Curtains that finish on top of a radiator push heat into the glass and out of the room, and the fabric discolours within a season or two. Either stop the drop about 2 cm above the sill, or go full length past the radiator. The in-between length is the one to avoid.
Photo to come
An older, visibly out-of-square recess with a tape across one diagonal — the wedge of daylight showing.
assets/images/measuring/window-out-of-square.jpgWhat it is: An opening that is not a true rectangle — corners off ninety degrees, walls bowed. Very common in older buildings and after replastering.
If your diagonal check came back more than 1.2 cm apart, stop planning a recess fit; nothing rigid will look right in it. Exact fit hides the problem completely — the covering overlaps the opening, so the wonky edge sits behind fabric where nobody sees it.
Photo to come
Sliding or French doors with a covering mounted above and wide of the frame, drawn back clear of the opening.
assets/images/measuring/window-sliding-doors.jpgWhat it is: Full-height glazed doors that slide sideways or swing open — patio doors, French doors, balcony doors.
The covering has to clear the door as it moves, and stack somewhere that does not block the opening. Mount well above the frame and run wide past both sides, so that when everything is drawn back the doorway is genuinely clear. Measure the finished size you want, not the door.
07 · Learn from others
Made-to-measure means cut to your figures, so a mismeasure is not covered by a normal return. These seven account for nearly all of them, and each takes under a minute to rule out.
Video to come
Each mistake shown being made, then corrected. Short — around 90 seconds.
assets/images/measuring/video/common-mistakes.mp4Watch: all seven, shown wrong then right
Using a cloth tape
It stretches under tension and reads long. Steel only.
Deducting "to be safe"
We deduct as well, and the two stack up. Send the true opening size.
Measuring in one place
The middle of a window is rarely its narrowest point. Three readings, smallest wins.
Assuming windows match
Two openings built the same week are routinely a centimetre apart. Measure both.
Copying the old blind for a recess fit
The old blind is already smaller than the opening. Copy it only at exact fit.
Swapping width and drop
Always width first, then drop — in your notes and in the order form.
Forgetting the handle
Open the window before you measure. A closed handle hides the real obstruction.
08 · Loose ends
Still unsure after reading these? Send us your numbers and a photo of the window before you order — that costs nothing and settles it.
Correct — nothing at all. Give us the true size of the opening and tell us the fit you want. Every product carries a different allowance for its brackets, its stack and its mechanism, and ours is applied against the exact specification you have chosen. A deduction you make on top of ours is the most common cause of a blind arriving too small.
The smallest, without exception. A covering sized to the widest point cannot pass the narrowest one, so it jams or scrapes. Sized to the narrowest, it clears the whole opening, and the extra millimetres at the wider points are invisible from a normal viewing distance.
Our order forms take centimetres to one decimal place. If your tape reads in inches or millimetres, convert before you write anything down, then work only in the converted figure — most errors of this kind come from converting a second time later and not noticing.
Fit outside it. Exact fit mounts the covering on the wall over the opening, so recess depth stops mattering entirely, and you get better light control as a bonus. For wooden blinds specifically, a narrower slat also needs less depth, so that is worth checking before you abandon a recess fit.
For an exact-fit replacement, measure the existing blind including its brackets and order at exact fit — same size, done. For a recess fit you must take the old blind down first: it is already smaller than the opening, so copying its size and then having us deduct again leaves you badly short.
Between 30 cm and 600 cm wide, and between 30 cm and 500 cm in drop. Anything outside that range is rejected by the order form rather than silently accepted. Bear in mind that very wide single blinds get heavy to operate — past about 240 cm we will usually suggest splitting into two.
Have us do it. Our paid measurement visit sends a professional to measure every window, record the fit type for each and flag anything awkward, and the sizes go straight onto your order. For a whole house, or anything unusual, it is the cheaper option once a single remake is priced in.
Enter them into any configurator and the price moves as you build the specification. Nothing is committed until checkout, and you can save a design and come back to it.