Outdoor Roller Shades and Exterior Solar Shades: Openness, Sizes, Mounting and Wind

Openness factor: 80, 90 or 95% solar screen fabric

Openness is how loose the weave is, given as a percentage. A shade with 10% openness lets about 10% of the light through the holes; sellers usually market the same fabric as 90% blockage. Phifer's SunTex line, a common exterior solar screen fabric, shows the pattern: SunTex 80 has roughly 20% openness, SunTex 90 roughly 10%, and SunTex 95 roughly 5%, blocking about 80%, 90% and up to 95% of the sun's rays.

Lower openness means more heat and glare control and less view. Covers and All describes 1% fabric as maximum privacy and heat rejection with a heavily restricted view, 3% as the most popular balance, and 10% as the loosest standard weave with the most light and airflow. Color matters too: darker fabric is easier to see through and cuts visible glare, while lighter fabric reflects more heat.

Daytime privacy reverses at night. When the patio or room is lit and it is dark outside, people can see in through any solar screen, so pair it with curtains or an indoor shade if night privacy matters.

Cordless, crank or motorized outdoor shades

Small and medium patio shades run fine by hand. Coolaroo's exterior roller shade, for example, uses a cordless roller clutch with a removable hand crank wand, so there is no loop of cord hanging down. For indoor window coverings, the CPSC's rule requires stock products to be cordless, have short cords (8 in or less) or have inaccessible cords; a cordless or crank shade avoids the same loop hazard outdoors where kids play.

Motorized shades make sense for wide openings, high headers and zipper-track systems, which are heavy to crank. SunSetter's EasyScreen zipper-track line, for example, runs on a Somfy motor with a remote and requires electricity. If there is no outdoor outlet near the header, budget for one: Angi lists $150 to $260 to install an outdoor outlet.

How to measure for outdoor roller shades: inside or outside mount

On a patio, the shade almost always goes outside mount: on the face of the beam or header, covering the full opening between posts. Measure the beam width you want to cover and the drop from the mounting surface to the floor or to the top of the railing. On a window you can mount inside the frame if it is deep enough, or outside on the wall around it.

Check the hardware before you drill. Coolaroo's instructions say the included screws are for wood only and to ask the retailer about other materials, so plan masonry or metal fasteners for stucco, brick or aluminum posts.

• Inside mount width: measure top, middle and bottom; order the smallest. The factory deducts about 1/8 in.
• Inside mount height: measure left, middle and right; use the largest.
• Inside mount depth: at least 1 1/4 in flat surface, or 1 3/4 in with a cassette valance.
• Outside mount width: measure the area and add 1 to 1 1/2 in per side to cut light gaps at the edges.
• Outside mount height: add 3 to 4 in if the brackets sit above the window frame.
• Roller fabric ships about 1/2 to 1 in narrower than the ordered width to make room for the brackets.

Outdoor roller shades in wind: free-hanging vs zipper track

A free-hanging roller shade is a sail with a bar at the bottom. Coolaroo includes bungee tie-downs for mild to moderate wind and tells owners to roll the shade up when not in use or before strong winds. Hold-down hooks or brackets at the floor or rail help in breezes, but they do not turn a free-hanging shade into a storm screen.

Zipper-track and side-channel shades lock the fabric edges into tracks on both sides, so the fabric cannot billow out. SunSetter, for example, rates its optional heavy-duty zipper track for wind up to 60 mph and adds a weighted bottom hem bar. Ratings like that come from the manufacturer for its own system; read your model's manual before leaving any shade down in a storm.

On motorized shades, a wind sensor can roll the shade up on its own when gusts start, which matters most when nobody is home.

Patio shades vs window shades

Exterior shades work better against heat than indoor ones because they stop the sun before it hits the glass. Phifer says its exterior sun control fabrics absorb and dissipate 65 to 97% of the sun's heat and glare before it reaches window or door glass, depending on the fabric.

On a covered patio, a roller shade fills the gap a roof cannot: low morning or afternoon sun coming in from the side. On a window, you have two options. A roller shade mounted outside the frame can go up and down with the seasons. A fixed solar screen (SunTex fabric in a screen frame) is cheaper and stays put, but it also cuts winter sun you may want. If you want the window shaded from above while keeping low winter sun, an awning is the better fit.