A sectional cover should be measured around the complete configuration that will remain outdoors, not around one seat module or the product’s marketing piece count. Record the widest width, deepest depth, and tallest height, note any chaise or table projection, and then apply the exact fit allowance published by the cover maker.
Quick Answer
Assemble the outdoor sectional in its storage configuration, remove items that will not stay under the cover, and measure the maximum outside width, depth, and height. Include arms, back cushions only if they remain in place, and every projection inside the covered footprint. Do not add a generic allowance; follow the selected cover manufacturer’s measuring instructions, ventilation design, and tie-down method.
Choose the Storage Configuration First
A modular sectional can be covered as one L-shape, a straight run, two smaller groups, or separate modules. Decide which arrangement will stay outside before measuring. The everyday layout may not be the best storage layout. A compact rectangle can be easier to cover and shed water, but only if moving the modules does not damage them and the connector system supports repeated changes.
Remove a coffee table or ottoman if it will be stored elsewhere. If it stays within the footprint, include its full projection and confirm it does not create a low point where the cover can sag. Do not place objects under a cover merely to reduce storage elsewhere unless the cover and furniture instructions allow that setup.
Make a Module Map
Sketch the configuration from above. Label the longest back run, the chaise or return, each arm, any curved section, and the highest back. For an L-shape, one “width” and one “depth” may be insufficient for a fitted L-shaped cover; the cover supplier may request several segment lengths. Follow its diagram and use the same orientation.
Measure solid frame-to-frame dimensions with the modules aligned and connected. Soft cushions can compress and give inconsistent readings. If back cushions remain under the cover, measure the highest normal position without crushing them. If they will be stored dry indoors or in a deck box, measure the frame as the instructions require.
Measure Width, Depth, and Height
Maximum width
Measure the widest outside span from the farthest left point to the farthest right point. Include armrests and any frame projection. Keep the tape straight rather than following curves or dipping between modules.
Maximum depth
Measure from the farthest front projection to the farthest rear point. On an L-shaped layout, this may be the chaise return rather than the seat depth. A table tucked in front may change the overall footprint if it stays under the same cover.
Maximum height
Measure from the surface under the furniture to the highest point that will be covered. Do not assume all modules have equal backs. An arm, adjustable backrest, cushion, or table accessory may be the highest point.
Write down the values immediately and label the units. Measure twice. If two readings differ, check whether the modules shifted or the tape was angled.
Do Not Invent a Fit Allowance
Cover brands vary in how they translate furniture measurements into cover size. Some instruct shoppers to choose a cover slightly larger than the furniture; others build an allowance into stated cover dimensions. Follow the current sizing chart for the exact product. A very tight cover can stress seams and be difficult to install. Excess material can flap, collect water, or touch the ground.
Check the finished cover length against the furniture height. Ventilation often depends on a deliberate gap near the bottom. Do not assume a cover should seal to the patio surface. Keep drains and designed vents unobstructed.
Plan for Water Shedding and Ventilation
A broad sectional creates a large horizontal area where water can pool. Use a support pole or other system only when recommended by the cover maker, and place it where it will not damage cushions or frames. Create a smooth slope without sharp contact points. Empty pooled water promptly according to the product instructions.
Cover only dry furniture and dry cushions unless the manufacturer explicitly directs otherwise. Ventilation cannot compensate for trapping saturated textiles. After rain, inspect the cover, tie-downs, and area beneath it. Let damp components dry fully before recovering them.
Check Tie-Downs and Wind Exposure
Identify where straps, buckles, elastic hems, toggles, or leg loops will attach. They should reach their intended points without crossing a walkway, rubbing a sharp edge, or interfering with moving parts. A furniture cover is not a severe-weather anchoring system. Follow local guidance and the sectional and cover instructions when wind or storms are expected.
Do not attach cover straps to railings, utilities, pool barriers, heaters, or other unrelated structures. If the cover cannot be secured as designed in the chosen configuration, change the layout or select a compatible cover.
Measure Again After Rearranging
Modular furniture invites layout changes, but the old cover dimensions may no longer apply. A straight sofa, L-shape, and separated conversation group have different footprints and water-shedding behavior. Re-measure after any major change and confirm that connector points and feet are stable before covering.
For rearrangement planning, use the modular sectional guide. If pieces drift before the cover goes on, review sectional connector troubleshooting.
Verified Sectional Examples for Measurement Practice
These live catalog examples use the approved Outdoor Furniture Authority tracking ID. Use their current listings to practice locating overall and module dimensions; they are not cover-fit guarantees. A cover must be selected from the exact measured configuration and its maker’s instructions.
As an Amazon Associate, we may earn from qualifying purchases.
The Rattaner example includes a cover in the current catalog result, making it useful for comparing the set’s configuration with the supplied-cover description.
View Rattaner 6-Piece Sectional on Amazon →
Use the Aoxun seven-piece listing to identify the overall layout and compare it with the individual seat and table components.
View Aoxun 7-Piece Sectional on Amazon →
The Qsun example can help demonstrate why a glass coffee table must be counted if it remains inside the covered footprint.
View Qsun 7-Piece Sectional on Amazon →
The KROFEM modular set offers a larger component count; map each item before deciding what will sit under one cover.
View KROFEM Modular Set on Amazon →
Compare the Aoxun aluminum listing’s overall footprint with the seat, table, and cushion elements that may change the highest or deepest point.
View Aoxun Aluminum Sectional on Amazon →
The PHI VILLA four-piece sectional illustrates why a smaller count does not automatically mean a small overall cover.
View PHI VILLA 4-Piece Sectional on Amazon →
Printable Measurement Record
- Storage configuration: L, straight, U, split, or separate modules
- Maximum overall width
- Maximum overall depth
- Maximum overall height
- Left and right return lengths for an L-shaped cover
- Items staying inside the footprint
- Cushions staying on the frame or stored separately
- Cover maker’s stated allowance
- Vent and tie-down locations
- Drainage slope and support method, if specified
Label and Store the Cover Correctly
Before removing a multi-part or fitted cover, note its front, back, left return, and right return. Follow the maker’s folding and storage directions, and let the cover dry fully before placing it in a container. A tightly folded damp cover can develop odor, staining, or material damage even when the fabric is intended for outdoor exposure.
Keep the measurement record, product model, care label, and tie-down diagram together. If the sectional layout changes next season, compare the new footprint with the old record before assuming the cover still fits. Replace damaged straps or torn seams using the manufacturer’s repair guidance rather than relying on a temporary tie that can flap or snag.
Frequently Asked Questions
Do I measure each sectional piece?
Record module dimensions for layout planning, but measure the complete storage configuration for a one-piece cover. A fitted L-shaped cover may require several segment measurements from its own diagram.
Should cushions be included in the height?
Include them only if they will remain in their normal position and the cover maker’s instructions say to measure that way. Store damp or removable cushions according to their product directions.
How much larger should the cover be?
Use the exact cover brand’s sizing guidance. Do not apply a universal number because some products build allowance into the listed dimensions and others tell shoppers what to add.
Can I cover the coffee table with the sectional?
Only if the selected cover is designed for that footprint and the table does not create a damaging peak or water pocket. Include the table in every relevant measurement.
Why does water pool on a sectional cover?
The cover may be too loose, the layout may create a broad low area, or the recommended support is missing. Follow the cover maker’s installation and support directions.
Can one cover fit every modular layout?
Usually not. Different configurations change width, depth, return lengths, tie-down positions, and water shedding. Re-measure after rearranging.
Final Verdict
Accurate sectional-cover sizing starts with the finished storage layout. Measure the widest, deepest, and tallest outside points, follow the chosen cover’s own allowance, and plan ventilation, support, and tie-downs before ordering. A careful measurement record is more reliable than product piece count or a generic size label.
Care reference: Covering should follow the furniture and textile directions. Current examples include POLYWOOD care guidance and Sunbrella upholstery care.