How to Build a DIY Retractable Pergola Canopy

1. Size the Canopy Fabric

   When fully extended, the canopy must be the size of the pergola's area, plus at least 20 percent longer to accommodate draping. Heavier cloth such as sailcloth will sag more; muslin and linen will sag less. Determine the look you wish to achieve when the canopy is extended. Tighter cloth has a trim, finished look. Cloth with deeper sags gives your pergola an airy, fanciful look. Find the area of your pergola by multiplying its length by its width.

   Tip

   Sailcloth can normally be ordered from a sailmaker's supply outlet in widths up to 60 inches. For mesh privacy screening, shop at a big box home center or landscape supply specialty store; widths of 4, 5, and 6 feet are standard. For muslin or linen, a fabric store is your best bet.

2. Stitch the Canopy Fabric (Optional)

   Since the canopy fabric rarely will come in widths that match your pergola's width, you'll need to decide whether you want to stitch together separate canopy strips or leave them separate.

   For example, a 12-foot wide pergola would require two strips of fabric, each 6 feet wide. You can use a sewing machine to sew the two runs of canopy fabric together. Sailcloth is too thick to sew comfortably by hand, but muslin and linen can be manually sewn. Another option is to run two or more separate canopy strips attached to the support bars, without stitched seams.

3. Cut the Canopy Support Bars

   The canopy fabric will be stabled to 2x2 cedar supports bars, which will then be suspended from support wires using eye screws that allow the canopy to slide back and forth.

   With a power miter saw or circular saw, cut 2x2 boards to the width of the canopy. Generally, plan on one board for about every 18 inches of the canopy's length, though the exact spacing is up to you. Increasing the number of boards creates a scalloped, ribbed look. Fewer boards produce larger, lower drapes.

4. Stain the Support Bars (Optional)

   Cedar wood naturally weathers to a silvery-gray color and its oils keep it protected for many years. But if you would like added protection or a different look, you may choose to treat the cedar boards with semi-transparent stain or solid color stain.

   Let the stain dry fully before proceeding to the next step.

5. Attach the Support Bars to the Canopy

   To attach the canopy fabric to the support bars:

   • Stretch the canopy out on a clean surface.
   • Using a tape measure and tailor's chalk or a carpenter's pencil, lightly mark intended support bar locations along the edges of the canopy fabric. For the canopy to slide properly, the support bars must be parallel to each other and all bars should be perpendicular to the sides of the canopy. Support bars should be located at each end of the canopy, as well.
   • At each pair of marks, slide a support bar under the canopy and staple the canopy to the bar. Repeat for every set of marks.

   Tip

   Make sure to use galvanized wire staples to secure the canopy fabric to the supports, as they will resist corrosion better than standard steel staples.

6. Install the Eye Screws on the Pergola

   Next, you'll install the six eye screws on the support beams, three on one beam and three on the opposite beam. The support beams are the pergola's chief horizontal load-carrying beams, often 2x6 or 2x8 lumber, upon which the upper structure rests. They are not the top-most lattice (designed to host trailing plants), nor are they the cross members (joists) directly below the lattice. The support beams are the structural members that rest on (or are bolted to) the vertical posts.

   Using a ladder, drill three equidistant pilot holes on one beam, slightly smaller in diameter than the eye screws. Position the holes as high as possible, while maintaining a 1-inch space above the holes so that the canopy will slide freely and clear any structural components directly above. Screw the three eye screws fully into place. Repeat for the opposite side.

7. Cut the Wire Rope

   Cut the wire rope into three lengths. Each length of wire rope should be equal to the distance between the two pairs of eye screws, plus another 10 percent, minimum, to allow for looping around the eye screws and securing with clamps.

8. Install the Wire Rope on the Eye Screws

   Looping the ends of the wire ropes around the screw eyes is a somewhat tricky operation:

   • First, fit a cable thimble through one of the eye screws, then slide the end of one of each wire rope through the eye screw and over the cable thimble so it fits into the thimble's groove.
   • At the other end of the wire rope, fit a cable clamp over the rope and slide it up to the thimble area so both strands of the wire rope are threaded through the clamp's opening.
   • With a wrench, tighten down the clamp so that the wire rope forms a tight loop over the thimble.
   • Repeat for the other two wire ropes and eye screws.

   The three wire ropes should now be anchored to the support beam at one end of the pergola, with the opposite ends of the wire ropes still hanging free.

9. Install the Eye Screws on the Support Bars

   Stretch out the canopy and lay it on a clean surface. The canopy can be oriented so that the wooden support bars are either above or below the canopy fabric. Installing the bars above the fabric gives the cover a clean look that emphasizes the draping. Installing the bars below the fabric means that the bars will be visible from below. This is a stronger attachment since the support bars, not just staples, are holding up the fabric.

   Attach three of the #10 eye screws on top of every support bar. Space the eye screws so that they match the spacing of the three eye screws you previously installed on the pergola beams. Be sure to drill pilot holes to avoid cracking the wood.

10. Trim the Wire Ropes and Attach Turnbuckles

    Extend each of the turnbuckles out as far as they will go by turning the two ends counter-clockwise to each other. Attach the three turnbuckles with the hook end to the three remaining eye screws on the pergola. Extend the free end of each wire rope to the eye end of the turnbuckles to get a general sense of where to cut the ends. Add 4 inches to your measurement and cut there, using wire cutters.

11. Slide the Canopy onto the Wire Ropes

    With a helper, thread each of the three wire ropes through the corresponding eye screws attached to the support bars.

12. Attach Thimbles and Clamps to the Wire Ropes

    Attach the remaining thimbles and clamps to the free ends of the wire ropes, in order to connect them to the eye end of the turnbuckles. Secure the hook ends of the turnbuckles to the pergola eye bolts. Turn the turnbuckles clockwise to tighten the wire ropes. Make them as taut as possible.

    Tip

    Lifting the canopy up as you secure the turnbuckles onto the eye bolts can be an awkward process. Having a helper or two assisting will make this work considerably easier.

13. Secure One End of the Canopy

    Since one end of the canopy will always remain in place, you will need to secure the end support bar so that it does not move. Drive 2 1/2-inch screws horizontally through the ends of the support bar to attach it to the pergola's vertical posts.

14. Attach the Deck Cleats to the Support Posts

    At the far end of the pergola, attach a deck cleat to the inside face of each of the pergola's two posts, about 4 feet above the bottom of the post.

15. Attach the Drawstring to the Canopy End

    Cut two pieces of nylon rope, each the length of your pergola plus another 4 feet. Tie each to the end support bar, one at each end. Drape each drawstring over a horizontal support beam at the end of the pergola.

    Pulling the drawstrings down will move the pergola canopy horizontally along the wire ropes to extend it. Loop the drawstrings around the cleats to hold them in place. Retracting the canopy will involve removing the drawstrings from around the cleats, and sliding the canopy back to the fixed end by hand.

Retractable Canopy Tips

To keep it looking nice, you should expect to replace your canopy fabric every few years, as exposure to wind, rain, and sun is sure to age the fabric. In colder climates where a deck or patio is not used during the winter months, you may want to take down the canopy and store it for the winter—or drape it with a protective plastic tarp over the winter.