Spring is coming. I don’t really care what Punxsutawney Phil said. I know because I am getting lots of requests to re-cover outdoor and RV cushions. A lady I know was telling me about the waterproofing spray she was going to buy to spray her outdoor cushions. We had a bit of a conversation about this, and I thought I should share some of it.
First of all, if you expect the covers to be totally waterproof, you will be disappointed. Unless you seal each line of stitching, glue the zipper shut, and evenly apply multiple layers of waterproofing, the cushion will not be totally impervious to water collection.
Walter collecting in the inner foam will mold and mildew. Hence ruined cushions.
The clever DIYer will make her outdoor cushions so the water runs through them and does not collect in the filler. Makes a lot of sense when you think about it, doesn’t it?
If you are making your cushions yourself, or having them made, ensure you use a foam or filler specifically designed for outdoor use. The most common outdoor cushion material is a quilt batt-like product. (Often made from recycled plastic bottles.) Water passes through the product, inhibiting mildew growth. Available one or two inches thick, it is stacked to the required depth and can be cut easily with scissors. It is available online and in large do-it-yourself home decor stores; it is priced about the same as high quality foam. Fabricland carries it as Fiber Form-Ext.
My current favorite is Dri-Fast. Thick polyethylene fibers are spun into a sheet typically 2 or 3 inches thick to create a product that is firm, does not support mildew growth and can be cut with an exacto-knife. Water passes through the material quickly and does not accumulate. It is about twice as expensive as foam, but some varieties are guaranteed for at least five years of outdoor use. It is available through upholsters and drapery workrooms.
The fabric used to cover outdoor furniture foam requires consideration as well. Good-quality outdoor fabric resists sun-bleaching and allows moisture to pass. If the filler is wrapped with a batting, it should not be glued in place as the glue will inhibit water passing though. Spend the extra money on top-quality materials now and you won’t be replacing the cushions in a few years.