Drapery Yardage Calculator
Effortlessly determine the fabric yardage needed for your custom draperies.
Drapery Yardage Calculator
Your Drapery Yardage Estimate
Fabric Length Per Panel = Finished Height + Hem Allowance + Top Hem Allowance (if not included in Hem Allowance) + any header/rod pocket allowance.
Pattern Repeat Adjustment: If a pattern repeat is used, add the repeat length to the Fabric Length Per Panel.
Fabric Breakdown Table
| Measurement | Value (inches) | Value (yards) |
|---|---|---|
| Finished Height | ||
| Hem Allowance (Top & Bottom) | ||
| Side Hem Allowance (Per Panel) | ||
| Pleat Allowance (Per Panel) | ||
| Pattern Repeat (if applicable) | ||
| Fabric Length Per Panel | ||
| Total Width for All Panels | ||
| Total Fabric Yardage Needed | N/A |
Fabric Usage Chart
What is a Drapery Yardage Calculator?
A drapery yardage calculator is a specialized tool designed to help homeowners, interior designers, and DIY enthusiasts estimate the precise amount of fabric required to create a set of curtains or drapes. Unlike general fabric calculators, this tool accounts for specific drapery construction details such as fullness, pleating, hems, and pattern repeats. Accurate estimation is crucial for drapery projects, as fabric is often the most significant cost. Using a drapery yardage calculator helps prevent under-ordering (leading to delays and potential dye lot mismatches) or over-ordering (leading to wasted material and increased expense). It simplifies the complex calculations needed to transform window measurements into a fabric order quantity, typically measured in yards.
Who should use it: Anyone planning to make or commission custom drapes. This includes DIY sewers looking to tackle their first drapery project, interior designers sourcing materials for clients, and homeowners seeking accurate quotes from workrooms. It's particularly useful for those working with patterned fabrics where pattern matching adds complexity to the yardage calculation.
Common misconceptions: A frequent misconception is that you simply measure the window and add a bit for hems. In reality, drapery construction involves many more factors. Another myth is that all fabrics are the same width or require the same amount of fabric for fullness. The calculator addresses these by allowing specific inputs for fabric width, desired fullness (implicitly through panel width and pleat allowance), and pattern repeats. Many also underestimate the need for extra fabric to manage pattern alignment across multiple panels.
Drapery Yardage Calculator Formula and Mathematical Explanation
The core of the drapery yardage calculator involves several sequential calculations to arrive at the total fabric needed. The process begins by determining the fabric required for a single panel, then scaling it up for all panels, and finally accounting for yardage conversion and potential pattern repeats.
Here's a breakdown of the key calculations:
- Fabric Length Per Panel: This is the vertical dimension of fabric needed for one panel. It starts with the desired finished height and adds allowances for construction.
Fabric Length Per Panel = Finished Height + Hem Allowance + Side Hem Allowance (x2 for both sides) + Pleat Allowance - Total Width for All Panels: This calculates the combined horizontal fabric needed if laid out flat. It's based on the finished width of each panel and the number of panels. Since drapery is often hung with fullness, the 'Finished Width' input might already account for some fullness, but the pleat allowance is added for constructing those pleats.
Total Width for All Panels = (Finished Width of One Panel + Pleat Allowance) * Number of Panels - Number of Fabric Widths Needed: This determines how many vertical cuts of fabric you'll need to achieve the Total Width for All Panels.
Number of Fabric Widths Needed = Total Width for All Panels / Fabric WidthThis result is rounded UP to the nearest whole number because you can't buy partial widths of fabric from a bolt. - Total Raw Fabric Length: This is the total length of fabric that needs to be cut from the bolt.
Total Raw Fabric Length = Fabric Length Per Panel * Number of Fabric Widths Needed - Total Fabric Yardage: Convert the Total Raw Fabric Length from inches to yards.
Total Fabric Yardage = Total Raw Fabric Length / 36 - Pattern Repeat Adjustment: If the fabric has a pattern repeat, you need to ensure that each panel can accommodate the full repeat and that patterns can align between panels. A common adjustment is to add the pattern repeat to the 'Fabric Length Per Panel' if the repeat is significant. For precise pattern matching across multiple panels, you might need more fabric than calculated if the repeat doesn't divide evenly into the panel length. For simplicity, this calculator adds the repeat to the panel length.
Adjusted Fabric Length Per Panel = Fabric Length Per Panel + Pattern RepeatThe calculator uses this adjusted length for subsequent calculations if a pattern repeat is entered.
A crucial aspect is rounding. The final yardage is typically rounded UP to the nearest half or full yard, depending on the fabric, project complexity, and fabricator's preference. Some calculators automatically round up to the nearest half or full yard for ease of ordering.
Variables Table
| Variable | Meaning | Unit | Typical Range |
|---|---|---|---|
| Finished Width of One Panel | The final desired width of a single drapery panel after construction. | inches | 25 – 75 |
| Finished Height of Drapery | The final desired length of the drapery from the rod or track to the bottom hem. | inches | 48 – 120+ |
| Number of Panels | The total count of individual drapery panels. | count | 1 – 4+ |
| Fabric Width | The usable width of the fabric bolt, excluding selvages. | inches | 40 – 110 |
| Pattern Repeat | The vertical distance from the start of one pattern motif to the start of the next. | inches | 0 – 30+ |
| Pleat Allowance | Extra fabric added to the finished width of a panel to create pleats (e.g., for pinch pleats, goblet pleats). | inches | 4 – 12 |
| Hem Allowance | Fabric added to the top and bottom edges for hemming. | inches | 6 – 10 (e.g., 3″ top, 3″ bottom, or 4″ top, 4″ bottom) |
| Side Hem Allowance | Fabric added to the side edges for side hems. Often 1″ per side, totaling 2″. | inches | 1 – 3 |
Practical Examples (Real-World Use Cases)
Example 1: Standard Pair of Lined Drapes
Scenario: A homeowner wants a standard pair of pinch-pleated drapes for a large living room window. They need to cover a window that results in finished panels that are 50 inches wide each. The desired finished height is 96 inches. They are using a decorative fabric that is 54 inches wide and has a pattern repeat of 18 inches. They plan for a generous pleat allowance of 6 inches per panel, a combined hem allowance of 8 inches (4″ top, 4″ bottom), and 2 inches for side hems.
Inputs:
- Finished Width of One Panel: 50 inches
- Finished Height of Drapery: 96 inches
- Number of Panels: 2
- Fabric Width: 54 inches
- Pattern Repeat: 18 inches
- Pleat Allowance: 6 inches
- Hem Allowance: 8 inches
- Side Hem Allowance: 2 inches
Calculation Steps (Conceptual):
- Fabric Length Per Panel: 96 (height) + 8 (hem) + 2 (side hem) + 18 (repeat) = 124 inches.
- Total Width for All Panels: (50 (width) + 6 (pleat)) * 2 (panels) = 112 inches.
- Number of Fabric Widths Needed: 112 inches / 54 inches (fabric width) = 2.07 widths. Rounded UP to 3 widths.
- Total Raw Fabric Length: 124 inches (length per panel) * 3 (widths needed) = 372 inches.
- Total Fabric Yardage: 372 inches / 36 inches/yard = 10.33 yards.
Result: The calculator would suggest approximately 10.5 to 11 yards of fabric, rounded up to the nearest half or full yard for ordering. This accounts for the pattern repeat and ensures enough fabric for all three widths needed to achieve the desired total panel width, plus construction allowances.
Example 2: Wide Single Panel Traverse Curtain
Scenario: A client needs a single, wide traverse curtain for a sliding glass door. The finished width required is 100 inches. The desired finished height is 84 inches. They've chosen a stunning textured fabric that is 60 inches wide and has no pattern repeat. They plan for a simple 4-inch top hem allowance and a 4-inch bottom hem allowance (totaling 8 inches). They will use a 1-inch allowance per side (totaling 2 inches for side hems) and require 8 inches of fullness (pleat allowance) to ensure smooth operation.
Inputs:
- Finished Width of One Panel: 100 inches
- Finished Height of Drapery: 84 inches
- Number of Panels: 1
- Fabric Width: 60 inches
- Pattern Repeat: 0 inches
- Pleat Allowance: 8 inches
- Hem Allowance: 8 inches
- Side Hem Allowance: 2 inches
Calculation Steps (Conceptual):
- Fabric Length Per Panel: 84 (height) + 8 (hem) + 2 (side hem) + 0 (repeat) = 94 inches.
- Total Width for All Panels: (100 (width) + 8 (pleat)) * 1 (panel) = 108 inches.
- Number of Fabric Widths Needed: 108 inches / 60 inches (fabric width) = 1.8 widths. Rounded UP to 2 widths.
- Total Raw Fabric Length: 94 inches (length per panel) * 2 (widths needed) = 188 inches.
- Total Fabric Yardage: 188 inches / 36 inches/yard = 5.22 yards.
Result: The calculator would recommend approximately 5.5 yards of fabric. This covers the single wide panel, ensuring enough length for hems and the required fullness, and uses two widths of the 60-inch fabric to achieve the total required width.
How to Use This Drapery Yardage Calculator
Using our Drapery Yardage Calculator is straightforward. Follow these steps to get an accurate fabric estimate for your custom curtains:
- Measure Your Window and Drapery Requirements:
- Finished Height: Measure from where the rod/track will be installed down to the desired finished length (e.g., sill, apron, or floor).
- Finished Width: Determine the desired finished width of each individual drapery panel when it's hanging closed. Account for fullness – a common recommendation is 1.5 to 2 times the window width divided by the number of panels.
- Number of Panels: Decide if you need one single panel or a pair (or more).
- Gather Fabric Details:
- Fabric Width: Check the product details for your chosen fabric. This is usually printed on the bolt and is the usable width.
- Pattern Repeat: If your fabric has a repeating pattern, measure the vertical distance from the start of one pattern motif to the start of the next. If there's no pattern, enter '0'.
- Determine Construction Allowances:
- Pleat Allowance: Estimate the extra fabric needed per panel for your chosen pleat style (e.g., 6 inches for pinch pleats, less for grommets).
- Hem Allowance: Decide on the depth for your top and bottom hems. A common amount is 8 inches total (e.g., 4″ top, 4″ bottom).
- Side Hem Allowance: This accounts for the fabric turned under on the side edges of each panel. Typically 1 inch per side, totaling 2 inches.
- Enter the Values: Input all the measurements and allowances accurately into the fields of the calculator.
- Calculate: Click the "Calculate Yardage" button.
How to Read Results:
- Primary Highlighted Result: This is the total estimated fabric yardage you'll need to purchase. It's rounded up to a practical amount for ordering.
- Key Intermediate Values: These show crucial steps in the calculation, such as the required length per panel, the total width needed, and how many fabric widths are used.
- Fabric Breakdown Table: Provides a detailed view of how each measurement contributes to the final fabric length.
- Chart: Visually represents the proportions of fabric used for different allowances and the final panel length.
Decision-Making Guidance: The yardage calculated is an estimate. Always consider ordering slightly more fabric (e.g., an extra half or full yard) to account for unforeseen issues, potential shrinkage during washing (if applicable), or future repairs. Consult with your workroom or seamstress if you have specific construction techniques or very large pattern repeats, as they might have tailored recommendations.
Key Factors That Affect Drapery Yardage Results
Several elements significantly influence the amount of fabric needed for draperies. Understanding these factors ensures you get an accurate estimate and avoid costly mistakes:
- Fabric Width: This is arguably the most critical factor after the dimensions. Narrower fabrics (e.g., 45″ or 54″) require more vertical cuts (widths) to achieve the desired total panel width, increasing the overall yardage needed compared to wider fabrics (e.g., 90″ or 110″). Wider fabrics can sometimes allow for a single panel drape or reduce the number of seams.
- Desired Fullness/Width: Draperies are rarely hung flat. Fullness, often expressed as a multiplier of the window width (e.g., 1.5x, 2x, 2.5x), dictates how wide the fabric needs to be. More fullness means wider panels and potentially more fabric widths or a larger total yardage. The calculator accommodates this via the 'Finished Width of One Panel' and 'Pleat Allowance'.
- Pattern Repeat: Fabrics with large or complex pattern repeats require careful layout to ensure motifs align correctly across panels and vertically. This often necessitates adding the repeat length to the fabric panel length, and sometimes purchasing extra fabric to perfectly match the pattern at seams or when cutting multiple widths. A '0' repeat simplifies calculations significantly.
- Pleat Style and Allowance: Different pleat styles (e.g., pinch pleats, goblet pleats, rod pocket with fullness) require varying amounts of extra fabric beyond the finished width to create the pleats. Pinch pleats typically require the most allowance, directly impacting how many fabric widths you'll need.
- Hem and Edge Finishes: Substantial top and bottom hems, as well as side hems, all consume vertical fabric length. Generous hems contribute to a more substantial, finished look but increase the raw fabric length required per panel.
- Lining and Interlining: While this calculator focuses on the face fabric, remember that lined draperies require separate fabric for lining and potentially interlining (to add body and insulation). The yardage for these layers is usually calculated separately but often based on similar dimensions, though they may not require pattern matching or pleat allowance in the same way.
- Shrinkage: Certain natural fibers (like cotton or linen) can shrink when washed or exposed to humidity. It's wise to pre-wash such fabrics before cutting or to factor in extra yardage to compensate for potential shrinkage, especially for floor-length drapes.
- Fabric Orientation: Most drapery fabrics are designed to be hung vertically, meaning the pattern runs parallel to the selvage. However, some fabrics might be printed railroaded (pattern runs across the width), which can drastically alter yardage calculations if not accounted for. This calculator assumes standard vertical orientation.
Frequently Asked Questions (FAQ)
Q1: How much extra fabric should I buy for mistakes or future repairs?
It's generally recommended to buy an extra half to a full yard of fabric beyond the calculated amount. This provides a buffer for any cutting errors, unforeseen pattern-matching challenges, or for future repairs if a panel gets damaged.
Q2: Do I need to account for shrinkage?
Yes, especially for natural fibers like cotton, linen, or silk blends. It's best to pre-wash the fabric according to its care instructions before cutting. If you don't pre-wash, add at least 1-2 inches to the height of each panel calculation to account for potential shrinkage after installation.
Q3: What is "fullness" in drapery and how does it affect yardage?
Fullness refers to the amount of fabric used beyond the exact window width to create folds and body in the drapery. A common fullness ratio is 2:1 (meaning the total fabric width is twice the window width). More fullness requires wider panels, which in turn increases the number of fabric widths needed and thus the total yardage.
Q4: My fabric has a large pattern. Do I need more yardage than this calculator suggests?
The calculator adds the pattern repeat to the panel length, which is a standard adjustment. However, if your pattern is very large or complex, and requires precise centering or matching across multiple panels, you might need additional fabric. Consult with a professional seamstress or drapery workroom for large-scale pattern matching. This calculator provides a strong baseline estimate.
Q5: Can I use this calculator for sheers or lightweight fabrics?
Yes, you can use the calculator for sheers and lightweight fabrics. However, the 'fullness' requirements might differ. Sheers are often hung with more fullness (e.g., 2.5x or 3x the window width) to create a soft, billowy effect. Adjust the 'Finished Width of One Panel' input accordingly to achieve your desired look.
Q6: What if my fabric is "railroaded"?
Railroaded fabric means the pattern runs across the width of the bolt, not along the length. If your fabric is railroaded, you can often use the fabric width as the panel height and calculate yardage based on the total required width. This can sometimes save yardage. This calculator assumes standard vertical fabric orientation; railroaded fabric requires a different calculation approach.
Q7: How do allowances (hem, pleat, side) impact the final look?
These allowances are crucial for proper construction and aesthetics. Hem allowances allow for finished edges that resist fraying and provide weight. Pleat allowances create the necessary fabric depth for folds and ensure the drape hangs beautifully. Side hems finish the edges neatly. Insufficient allowances can lead to a skimpy or poorly constructed curtain.
Q8: Should I round my final yardage up to the nearest half or full yard?
Yes, always round your final yardage calculation up. Fabric is sold by the yard (or sometimes half-yard increments at fabric stores). It's better to have a little extra than to run short. Most fabricators recommend rounding to the nearest half or full yard for ease of ordering and to account for any slight variations.