How to Clean an Awning: Fabric, Mildew and Winter Care in Portland

Monthly

Brush and hose off with clean water to keep dirt from setting in

2–3 yrs

How often Sunbrella says a thorough cleaning is needed in most places

15 min

Longest Sunbrella lets its bleach solution soak on stubborn stains

24–48 h

EPA’s window for drying wet materials before mold starts

Before you decide an awning is worn out, check whether it’s just dirty. A season of pollen, fir needles, road grime and drizzle leaves a gray film, and in a Portland winter that film is what mildew grows on.

The good news: cleaning an awning is a hose-and-brush job you can do without taking it down. Here’s the method the fabric makers recommend, what to do about mildew, and how to put an awning to bed for the rainy season.

Why do awnings get dirty and mildewed in Portland?

Because mildew feeds on dirt, and Portland keeps it damp. Sunbrella says its fabrics don’t promote mildew growth, but mildew can grow on dirt and other substances left on the fabric. The EPA puts the rule simply: “The key to mold control is moisture control.”

Portland International Airport averages 36.9 inches of rain a year, and nearly three-quarters of it falls October through March. An awning that goes into that season clean, dry and free of leaves comes out of it looking far better than one that doesn’t.

What you need to clean an awning

• Soft-bristle brushNever a hard-bristled brush or anything that abrades the fabric.
• Garden hoseClean water for the pre-rinse and the final rinse.
• Mild soapSunbrella names Woolite or Dawn dishwashing liquid.
• BucketFor mixing the cleaning solution.
• Household bleachOnly for stubborn stains or mildew on acrylic fabric like Sunbrella.
• Fabric guardSunbrella recommends 303 Fabric Guard to restore water repellency.

Work from a stable ladder, keep clear of power lines, and leave anything you can’t reach safely to a pro. That goes double for second-story awnings.

How to clean an awning, step by step

This is Sunbrella’s method for cleaning awning fabric while it’s still on the frame. It works for most solution-dyed acrylic awnings.

1. Brush off loose dirtDry leaves, needles, cobwebs and grit, with a soft-bristle brush.
2. Hose it downWet the whole awning with clean water, top and underside.
3. Mix the solutionWater and a mild soap, such as Woolite or Dawn dishwashing liquid.
4. Wash with a soft brushGently. Avoid excessive scrubbing and anything that will abrade the fabric.
5. Let it soak inGive the solution time to work into the weave.
6. Rinse thoroughlyUntil no soap residue is left.
7. Air-dryPick a dry day so the fabric dries completely.

How to remove mildew and stubborn stains from an awning

When soap and water aren’t enough, Sunbrella’s stubborn-stain method uses diluted bleach. It’s written for Sunbrella’s solution-dyed acrylic; for vinyl or any other fabric, check the maker’s care guide before using bleach.

• Re-treat after bleach. Sunbrella says the fabric will need retreatment for water and stain resistance after a bleach cleaning. Clean, let it dry completely, then apply a fabric guard in a well-ventilated area.
• Roof runoff and greasy stains can need a strong degreaser, per Sunbrella.
• Protect what’s underneath. Rinse plants, siding and decking below with clean water so bleach runoff doesn’t sit on them.

How to clean each type of awning

Not sure what your awning is made of? Most custom fabric awnings today are solution-dyed acrylic; canvas vs. acrylic awning fabric explains how to tell. If we made it, call the shop: we likely have the fabric on file.

Retractable awnings: dry it before you roll it up

A retractable rolls its fabric tight onto the roller, so anything wet or dirty goes into the hood with it. Three habits keep one clean and working:

1. Clean it fully extendedSo you can reach the whole fabric, then let it dry open on a dry day.
2. Close it when the weather turnsSummerSpace advises keeping retractables closed in rain, hail, high winds and snow; pooled water can make the fabric sag over time.
3. Dry it after a wet retractIf you had to close it damp, run it back out on the next dry day. The EPA advises drying wet materials within 24–48 hours to prevent mold growth.

Motorized awning acting up after a storm? Somfy notes that if an awning retracts on its own every 30 to 60 minutes with no wind, the wind sensor’s batteries need replacing. More fixes are in retractable awning motor not working?

An awning care calendar for Portland

Matched to the rain. Bars show normal precipitation at Portland International Airport for each season.

1. Spring Mar–May

   9.4 in

   Brush off winter grime and hose it down. Look over seams, stitching and fabric before the retractable goes out for the season.

2. Summer Jun–Sep

   4.2 in

   Brush and rinse with clean water once a month. Retract for wind and the odd summer storm.

3. Fall Oct–Nov

   8.9 in

   The big clean: wash, rinse, air-dry completely, then retract for winter. Clear leaves off fixed awnings.

4. Winter Dec–Feb

   14.5 in

   Keep retractables in. Raise rope pull-ups for light. Sweep off debris after storms; book any recover now.

Precipitation: National Weather Service Portland, NCDC climate normals 1991–2020. Seasons sum to the airport’s 36.9-inch annual normal.

How to get an awning ready for a Portland winter

• Clean it in early fall, on a dry stretch, so it goes into the wet months without the dirt mildew feeds on.
• Let it dry completely before a retractable goes in for the season.
• Keep leaves and needles off fixed awnings; a wet pile holds moisture against the fabric for weeks.
• Raise rope pull-up awnings. They’re built to go up in winter to let light in and drop again for summer.
• Check the wind sensor batteries on a motorized retractable before the storm season.
• Look for frayed seams, tears or a sagging frame, and get them fixed in the off-season, not the week you want shade.

When cleaning isn’t enough: recover or repair

If the frame is straight and solid but the fabric is faded, torn or stained deep, it usually needs a recover: a new cover sewn in our shop for the frame you already have. If we originally installed the awning, its specs are likely on file, and hard-to-find fabrics can often be matched through the International Fabrics Association database.

We also offer cleaning and maintenance, and we’re happy to point you to pressure-washing companies too. See awning repair and recovering, or read when to recover, repair or replace for the signs.

After they were done hanging the screens, they walked us through the operation and maintenance instructions.

Shopping for a new awning instead? Types of awnings compared lays out retractable, fixed, metal and freestanding side by side.