The official way to clean is:
· Brush off loose dirt.
· Hose down.
· Prepare a cleaning mixture of water and mild, natural soap
(no detergents). (Ivory soap, cut off flakes--not Ivory snow)
· Use a soft bristle brush to clean.
· Allow soap to soak in.
· Rinse thoroughly.
· Air dry.
If stubborn stains persist, you can use a diluted chlorine bleach/soap mixture for spot cleaning of
mildew, roof run-off and other similar stains.
Prepare a special cleaning mixture:
· Four ounces (half cup) of chlorine bleach.
· Two ounces (one-fourth cup) of natural soap.
· One gallon of water.
· Clean with soft bristle brush.
· Allow mixture to soak for up to 20 minutes.
· Rinse thoroughly.
· Air dry.
· Repeat if necessary.
For retreating (increasing waterproofness):
Clean as above, Air dry, then apply several light coasts of 303 Aerospace protectorant for fabric (not for vinyl). A 15 oz bottle will treat 50 sq feet. Two light coats are better than one heavy coat.
I have cleaned "oyster" off white Sunbrella multiple times and have had it last over 10 years (with re-stitching)--using Gortex thread will allow the seams to last much longer.