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Join Date: Sep 2005
Location: New Westminster, BC
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IIRC the manufacturer recommends 303 Fabric Guard (also a 3m product, if I'm not mistaken)
Washing sunbrella in strong detergent breaks it down so regular trips through the washing machine are not recommended unless you are using Woolite as opposed to a true detergent.
Water will eventually wick through if the detergent-washed fabric is not treated afterwards.