Traditional sealers and stains used to cover deck wood usually contain unhealthy chemicals. Some homeowners instead opt for green products made from organic materials. Green products are sold in stores. However, sealers can be made at home. Homemade sealers protect wood from moisture, mold, insects and direct sunlight.

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Direct sunlight can damage unsealed wood decking.

Milk Formula

A basic sealer can be made from a mixture of milk and lime. This mixture is made by mixing an ounce of powdered lime into a quart of skim milk. Adding chalk adds thickness. A simple milk formula will provide a base coat sealer that can be covered with other paint, oil or traditional sealant.

Cottage Cheese Sealer

A cottage cheese sealer is made by mixing lime and cottage cheese. Gradually adding water will allow the lime to react with the cottage cheese curds, creating a consistent mixture. Cottage cheese sealant is ready to use when the curds dissolve after a few hours. A thicker sealant is created by adding powdered milk.

Linseed Oil

Boiling linseed oil and mixing it with other agents is a suitable mixture for sealing decks and outdoor furniture. The most effective ingredients in a linseed oil sealer are paraffin or bees wax, turpentine, mineral spirits and pentachlorophenol (penta). Wax creates a barrier between moisture and deck wood. Pentachlorophenol prevents mildew from forming. Wax must also be melted before it is mixed with other agents. Pigment powder or natural ingredients can be added for desired colors.

Color

Homemade paints and sealers are colored by adding a variety of agents. While using pigment powder is the easiest way to add color to a sealer, turning natural ingredients such as berries, bark and leaves into dye is also effective. Each can be crushed and simmered to create vibrant color options.