Choosing the right curtain pole or track starts with one important step: accurate measurement. A pole that is too short can leave unwanted gaps around the window, while an oversized pole may look unbalanced or create fitting difficulties. The same applies to curtain width and drop. Even a high-quality pair of curtains can look poorly fitted when the measurements are wrong.
For homeowners planning a window upgrade, how to measure curtains is therefore more than a basic DIY question. The measurements determine the pole length, curtain fullness, finished drop and overall appearance of the window.
A good measuring process also makes it easier to choose between traditional curtain poles, curtain tracks, double rails and specialist solutions for bay windows or doors.
This guide explains how to measure windows, curtains, poles and tracks accurately, with practical advice for UK homes. It also covers eyelet curtains, bay windows, net curtains and the key measurements required before ordering a new curtain pole.
What Is Needed Before Measuring?
A small amount of preparation can make the process considerably easier.
The following equipment is recommended:
- A steel tape measure
- Pencil and paper
- Step ladder where necessary
- Spirit level for checking fitting positions
- Someone to assist when measuring large windows
A steel tape measure is preferable to a fabric tape because it is more rigid and less likely to stretch. Measurements should be recorded in centimetres and checked at least twice before ordering. The first decision is also important: is the pole or track already fitted?
If it is already installed, the existing pole or track can usually provide the most useful measurement. If nothing has been fitted, the window opening needs to be measured first, followed by an allowance for the curtain pole or track.
How to Measure for Curtain Poles
One of the most common questions from homeowners is how to measure curtain poles correctly. The basic principle is simple. The pole should normally extend beyond both sides of the window so the curtains can move away from the glass when opened.
Step 1: Measure the window width
Measure the window recess from one outer side to the other. Do not automatically assume that the window width should be the same as the finished pole length. A curtain pole generally needs additional space beyond the window.
Step 2: Add an extension on both sides
For many standard installations, allowing approximately 10–20cm beyond each side of the window provides useful clearance.
For example:
Window width: 180cm
Left extension: 15cm
Right extension: 15cm
Recommended pole length: approximately 210cm
Step 3: Consider the finials
When calculating curtain pole dimensions, it is important to distinguish between the actual pole length and the overall decorative length. Finials sit at the ends of many curtain poles. Their size can affect the total visual width of the installation.
How High Should a Curtain Pole Be Above the Window?
Another important measurement concerns the vertical position.
Many installations place the pole around 10–20cm above the window recess, depending on the room and available wall space. A higher position can create the impression of a taller window and allow the curtains to fall more naturally.
The question of how high the curtain pole is above the window does not have one universal answer.
Consider:
- Ceiling height
- Window proportions
- Existing coving
- Radiators
- Curtain length
- Available wall space
- Pole diameter and bracket design
How to Measure Curtain Tracks
Curtain tracks provide a discreet alternative to decorative poles. They are particularly useful where the homeowner wants the fabric to remain the visual focus. The measurement process begins with the same principle used for poles: determine the window width and decide how far the track should extend beyond the opening.
- For an outside-recess installation, an additional allowance on each side is normally desirable.
- For an inside-recess installation, the available recess width becomes the critical measurement.
Outside recess
Measure the window width and decide how much additional track is required on either side.
Inside recess
Measure the recess at several points because walls are not always perfectly square.
How to Measure Curtain Width
Understanding how to measure curtain width is essential because curtain width is not always the same as window width.
Curtains need fullness. The amount required depends on the heading style and the desired appearance. For example, eyelet curtains generally require more fabric than a flat, minimal treatment. Pencil pleat curtains also need enough material to create their intended folds. If the pole or track is already fitted, measure the usable pole or track width rather than simply measuring the glass.
This distinction is one of the most important points in any curtain measuring guide.
Example
Suppose a curtain pole measures 200cm. Two curtains may each need to provide approximately 200cm of fabric width for a fuller appearance, depending on the manufacturer's fullness recommendation. The final requirement should always be checked against the curtain supplier's sizing instructions because ready-made curtains are available in different widths and may be sold as pairs.
How to Measure for Eyelet Curtains
Eyelet curtains are designed to slide directly onto a curtain pole. As a result, the pole measurement and the curtain measurement need to work together. For anyone asking how to measure for eyelet curtains, the first step is to establish the pole length. Measure the pole across its usable length, excluding decorative finials where appropriate. The curtain drop is then normally measured from the top of the pole to the desired finishing point.
Eyelet curtain drop
Measure from the top of the pole, rather than from the bottom. This is important because the fabric sits above the pole through the eyelets. The required finished drop could be:
- To the windowsill
- Slightly below the sill
- To the floor
- Slightly above the floor
How to Measure Curtain Length
Curtain length is normally measured from the point where the curtain will hang to its intended finishing point. The three most common options are:
Sill length
The curtain finishes around the windowsill area. This works well for smaller windows and rooms where floor-length curtains are impractical.
Below-sill length
The fabric extends below the sill but does not reach the floor. This can be useful for windows positioned above furniture or radiators.
Floor length
The curtain extends close to the floor for a more formal appearance.
Before finalising the drop, check for:
- Radiators
- Floor vents
- Furniture
- Uneven flooring
- Window handles
- Doors opening into the curtain
Standard Curtain Sizes in the UK
There is no single universal curtain size that works for every UK window. Ready-made curtains are available in a range of widths and drops.
Common retail dimensions can include drops around:
- 137cm
- 160cm
- 180cm
- 228cm
- 229cm
- 274cm
However, these should be treated as common retail options rather than mandatory standard curtain sizes UK measurements. The correct size depends on the actual window, pole or track and the desired fullness. For this reason, buying curtains based solely on a perceived standard size can result in poor coverage.
Instead, accurate curtain measurements UK homeowners take themselves should be compared with the supplier's available sizes.
How to Measure Curtains for a Window
For homeowners wondering how to measure curtains for a window, the process can be simplified into two measurements:
Width + Drop
First establish the usable width of the pole or track. Then measure from the correct hanging point to the required finished length. The heading style determines the starting point.
For example:
|
Curtain heading |
Starting point for drop |
|
Eyelet |
Top of curtain pole |
|
Pencil pleat on pole |
Hook position |
|
Pencil pleat on track |
Top of track |
|
Tab top |
Top of pole |
How to Measure for Curtains and Rods
For traditional interiors, a wrought iron curtain pole can become part of the overall design rather than simply a functional fitting. When learning how to measure for curtains and rods, the homeowner should measure the window first and then establish the required pole extension.
A useful planning sequence is:
- Measure the window width.
- Check available wall space.
- Decide the desired extension beyond each side.
- Calculate the pole length.
- Select the correct pole diameter.
- Check bracket requirements.
- Measure the curtain drop.
- Confirm curtain fullness.
- Check that the curtain heading is compatible with the pole.
Choosing the Right Curtain Pole Length
Curtain pole length should be based on the installation rather than the curtain packaging alone. For example, a 180cm-wide window might require a pole longer than 180cm if the design calls for the curtains to stack beyond the window. Longer poles can also provide better access to natural light when curtains are fully open.
For larger windows, wider spans may require additional support brackets. The weight of the curtain fabric should also be considered. Heavy lined curtains require stronger support than lightweight voile or net curtains. This is where the construction and diameter of the pole become important.
Measuring for Wrought Iron Curtain Poles
Wrought iron poles offer a particularly strong combination of functionality and traditional character. They can complement period properties, country-style interiors, industrial schemes and contemporary rooms where a contrasting metal finish is preferred.
When measuring for a wrought iron pole, the same basic width principles apply. The measurement should account for:
- Window width
- Side returns
- Bracket position
- Finial size
- Curtain fullness
- Curtain weight
- Available wall space
How to Measure a Bay Window for Curtains
Bay windows require greater attention because the installation follows more than one direction. For anyone asking how to measure a bay window for curtains, each section should be considered individually. Start at one side of the bay and measure each section between the relevant points. Record every measurement separately.
For example:
Section 1: 90cm
Section 2: 120cm
Section 3: 90cm
The combined measurement is:
90 + 120 + 90 = 300cm
However, the final pole or track arrangement also needs to account for corners, brackets, joints and the way the curtains will operate. Bay windows may require specialist bay poles or carefully planned multiple sections rather than one standard straight pole.
How to Measure for Curtains in a Bay Window
The curtain measurement depends on the selected bay pole or track configuration. First establish the complete hanging route. Then determine the curtain drop from the appropriate hanging point. For a floor-length treatment, measure down to the intended floor position at several points. Older properties can have uneven floors, so checking more than one point is worthwhile.
A made-to-measure solution can be particularly useful when the bay has unusual angles or dimensions. For homeowners searching for a made to measure curtain pole, specialist sizing can provide a better solution than trying to adapt a standard product to a complicated bay.
How to Measure for Net Curtains
Net curtains and voiles are generally measured differently from heavy decorative curtains because fullness is a major part of their appearance. First measure the width of the pole, track or recess. Then decide how full the net should appear.
A common approach is to use approximately 1.5 times the available width for a moderate gather and up to 2 times the width for a fuller appearance. The exact ratio should be checked against the supplier's recommendations.
Curtain Pole Sizes and Dimensions: What to Check
When comparing curtain pole sizes, length is not the only measurement that matters.
The following specifications should be checked before purchase:
Pole length
This determines whether the pole will span the required installation area.
Pole diameter
The diameter affects appearance, curtain compatibility and perceived strength.
Bracket projection
The bracket needs to hold the pole far enough from the wall for the curtains to move freely.
Finial dimensions
Decorative finials add to the overall visual footprint.
Weight capacity
Heavy curtains may require additional brackets or a stronger pole.
Why Accurate Measurements Matter
The right measurements influence much more than whether curtains physically fit.
Correct sizing helps curtains:
- Cover the window effectively
- Open without obstructing excessive glass
- Hang with an attractive fullness
- Avoid unnecessary fabric pooling
- Clear radiators and furniture
- Sit correctly around bay windows
- Operate smoothly
- Complement the proportions of the room
Final Buying Advice
A successful curtain installation begins before the first bracket is drilled. Accurate measurements allow homeowners to select a pole or track that suits the window, curtain style, fabric weight and room proportions.
The most important measurements are the window width, fitting width, curtain width and finished drop. Eyelet curtains require particular attention to the pole and eyelet relationship, while bay windows require separate measurements for each section.
Homeowners should also check pole diameter, bracket projection, finial dimensions and support requirements before placing an order.
For those looking to combine practical performance with a distinctive traditional finish, SG Curtain Poles offers wrought iron poles, rods and rails for curtains alongside relevant curtain hardware. Accurate measuring makes it easier to select the right product and achieve a polished finished installation.
Frequently Asked Questions
1. How much wider should a curtain pole be than the window?
A curtain pole will generally look and work better when it extends beyond both sides of the window. An allowance of around 10–20cm on each side is often suitable, although the ideal extension depends on the available wall space, curtain thickness and desired appearance.
2. Should curtain width be the same as the window width?
No. Curtain fabric needs additional width to create folds and fullness. The amount required depends on the curtain heading and the style of finish. Eyelet, pencil pleat and gathered curtains can all require different fullness ratios.
3. How do you measure for eyelet curtains?
Measure the usable length of the curtain pole, then measure the required drop from the top of the pole to the desired finishing point. The eyelet diameter should also be checked against the pole diameter to ensure the curtains can move smoothly.
4. How do you measure a bay window for curtains?
Measure each section of the bay separately rather than treating the entire window as one straight opening. Record the measurements between corners and consider the position of brackets, joints and the way the curtains will open. Complex bays may benefit from a specialist or made-to-measure pole.
5. How high should a curtain pole be above the window?
There is no fixed height for every installation, but positioning the pole around 10–20cm above the window is commonly suitable where the wall space allows. A higher position can make the window appear taller, while the final position should also account for coving, ceilings, radiators and curtain length.
