Getting your curtain measurements right is the difference between window treatments that look professionally installed and those that appear hastily put together. While measuring might seem straightforward, there are important nuances that many homeowners miss. This guide will walk you through the complete measuring process, ensuring your sheer curtains hang perfectly every time.
The good news is that sheer curtains are generally more forgiving than structured drapes or Roman blinds. Their lightweight, flowing nature means minor measurement variations are less noticeable. However, getting the fundamentals right will still make a significant difference to the final result.
Before You Start: Tools You'll Need
Before taking any measurements, gather these essential tools:
- Steel tape measure: A retractable metal tape at least 3 metres long. Avoid fabric tape measures as they can stretch and give inaccurate readings.
- Step ladder: Essential for reaching the top of tall windows safely.
- Notepad and pen: Write down measurements immediately. Don't rely on memory.
- Calculator: For calculating fullness ratios and total fabric requirements.
Always use a stable step ladder when measuring high windows. Never stand on chairs, tables, or other furniture that could tip or slide. Have someone hold the ladder if possible.
Understanding Width Measurements
Width is typically the first measurement you'll take, but it's crucial to understand what you're actually measuring. The key principle is this: you're measuring for the curtain rod, not the window itself.
Rod Placement Width
For the best visual result, your curtain rod should extend 15-25 centimetres beyond each side of the window frame. This extension serves two important purposes: it makes the window appear larger, and it allows the curtains to stack completely clear of the glass when open, maximising your view and light.
If your rod is already installed, simply measure the rod length from end to end, excluding any decorative finials. If you're installing a new rod, measure your window frame width and add 30-50 centimetres to determine your ideal rod length.
Calculating Curtain Width: The Fullness Factor
This is where many people go wrong. Curtain width is not the same as rod width. Sheer curtains require "fullness" - extra fabric width that creates the beautiful gathered, flowing appearance that defines quality window treatments.
Multiply your rod length by 2 to 2.5 for proper sheer curtain fullness.
- Standard fullness (2x): Rod length x 2 = Total curtain width needed
- Generous fullness (2.5x): Rod length x 2.5 = Total curtain width needed
Example: 180cm rod x 2.5 = 450cm total curtain width
For sheer curtains specifically, a higher fullness ratio (2.5x) is generally recommended. Because the fabric is semi-transparent, sparse gathering can look thin and insubstantial. The extra fabric creates a luxurious, layered effect that makes sheers look their best.
Understanding Length Measurements
Length measurements determine where your curtains will fall. There are several standard options, each creating a different aesthetic:
Sill Length
The curtain ends at or 1-2 centimetres above the window sill. This length works well in kitchens, bathrooms, or any area where floor-length curtains would be impractical due to furniture placement, radiators, or traffic flow. Sill-length sheers provide a neat, casual appearance.
Below Sill (Apron Length)
The curtain extends 10-15 centimetres below the sill. This length provides slightly more coverage and a more finished appearance than sill length while still keeping fabric away from the floor.
Floor Length
The most popular choice for living areas and bedrooms, floor-length curtains extend to 1-2 centimetres above the floor. This length creates an elegant, proportioned look without fabric dragging on the ground and collecting dust. For sheers specifically, this slight hover is important as the lightweight fabric can easily catch under furniture or be stepped on.
Puddle Length
Also called "breaking" or "pooling," this style adds 5-15 centimetres of extra length that pools on the floor. While romantic and luxurious in appearance, puddled curtains require more frequent cleaning and don't work well in high-traffic areas. This style is best reserved for formal spaces that see less daily use.
Always measure length from where the curtain will hang on the rod to your desired endpoint. For most header styles, this is from the top of the rod. For grommet curtains, measure from just above the rod. For pinch pleats on a track, measure from the bottom of the track gliders.
Step-by-Step Measuring Process
Follow these steps for accurate measurements:
Step 1: Determine Rod Position
If your rod is installed, skip to Step 2. If installing a new rod, mark where you want it positioned. Standard practice is 10-15 centimetres above the window frame, though mounting closer to the ceiling makes windows appear taller. Mark both the height and where the rod brackets will go.
Step 2: Measure Width
Measure the full length of the rod (or planned rod length) from end to end. Write this measurement down as your "rod width." Then calculate your total curtain width by multiplying by your chosen fullness factor (2 to 2.5).
Step 3: Determine Panel Configuration
Decide whether you want one large panel, two panels that meet in the middle, or multiple panels. Most windows look best with two panels. Divide your total curtain width by the number of panels to find each panel's width.
Step 4: Measure Length
Hook your tape measure at the rod height (or your marked position) and extend it down to your desired length. Measure in at least two spots, as floors and ceilings are often not perfectly level. If measurements differ, use the shorter one to ensure the curtain doesn't drag on the floor at any point.
Step 5: Record Everything
Write down all measurements clearly, including which window they're for if you're measuring multiple windows. Note your chosen fullness ratio, header style, and length preference.
Special Window Situations
Bay Windows
For bay windows, measure each section separately. You can use individual panels for each window segment with a continuous rod that follows the bay's angles, or install separate rods for each section. Consider how you want the curtains to stack when open.
French Doors
Curtains for French doors need extra consideration for door operation. Measure from above the door to the floor, ensuring curtains can be pulled clear of the door swing. Consider tiebacks or holdbacks to keep fabric away when doors are in use.
Sliding Doors
For sliding glass doors, ensure your rod extends far enough to allow curtains to stack completely on one or both sides without blocking the door's operating path. Measure the entire door width plus the stackback area needed.
Standard Australian windows often come in these widths: 600mm, 900mm, 1200mm, 1500mm, 1800mm, 2100mm, and 2400mm. Having these references can help you estimate fabric requirements when comparing products online.
Common Measuring Mistakes to Avoid
Learning from others' mistakes can save you time and money:
- Measuring the window, not the rod: Always base width calculations on where the curtains will actually hang.
- Forgetting fullness: Flat curtains look cheap. Always multiply your rod width for proper gathering.
- Not accounting for header style: Different headers sit differently on the rod. Grommet curtains, for example, hang below the rod by the grommet diameter.
- Assuming windows are identical: Even windows that look the same may have slight variations. Measure each one individually.
- Measuring only once: Always double-check your measurements before ordering.
Ordering Curtains: Final Considerations
When ordering curtains based on your measurements, keep these points in mind:
Check whether the listed curtain width is per panel or total. A listing showing "140cm width" typically means 140cm per panel, so you'd receive 280cm total width with a pair. Ensure this matches your calculated requirements.
Some manufacturers list "flat" width while others list "gathered" width. Flat width is the actual fabric measurement, while gathered width accounts for the curtain's appearance when hung. Most quality retailers list flat width.
For length, check where the manufacturer measures from. Most measure from the top of the header, but some measure from the bottom of the header or from specific hardware points.
With accurate measurements in hand, you're ready to shop confidently for sheer curtains that will fit your windows perfectly. Take your time with this process, and you'll be rewarded with beautiful results that make your home look professionally styled.