Owners of most types of wood decks find they need to apply a new coat of stain every two to four years depending on several factors:

• The quality and type of wood.
• Quality of past deck staining.
• How often the deck is used.
• Weather, particularly the amount of snow and how long it was on the deck.

There are two types of deck stain … oil-based and water-based. Water-based stains are also referred to as acrylic or latex stain.

The first, and most important, step when staining an existing deck is to determine what type of stain has been used on the deck in the past. This is important because water-based deck stains will typically stick to oil-based stains but oil-based stains typically won't, if ever, stick to water-based stains.

Identifying the type of stain used in the past can be done in several ways:

• Find the can with the stain remaining from the last time you stained your deck and check the label.
• Recall how you washed your hands and clean the brushed you used to stain your deck. If you used soap and water it was a latex stain. Mineral spirit use shows that an oil-based deck stain was used.
• Contact a reputable, professional painter who may be able to identify the type of stain used.

If you are able to use oil-based stain Eric Morud, of TruNorth Painting, recommends you staick with it. TruNorth stains several hundred decks a year and that experience has shown that oil-based stains penetrate the wood more deeply to better preserve the character of the wood and provide a finish that better highlights existing wood grains.

The second choice for homeowners staining their deck is deciding what style of stain to use. Styles range from clear to solid stain can act kind of like a paint. This choice also depends on what stain has been used on a deck in the past.

You are able to move from using a clearer stain "up" to more solid stain, but you can't move from a more solid stain down to a clearer one, Morud said.

The clearer the stain typically the less UV protection from the sun the stain offers and the quicker it will fade. A clear stain finish may also require an annual staining.

The more "solid" the stain is -- the more color and pigment included in it -- the longer the stain will last, but the more susceptible it is to peeling and flaking. Also, the more solid the stain the less apparent the wood grain.

Lastly, there is a choice in cost of deck stains. Typically the less expensive the stain the more likely it is to tint, or discolor, the wood. The more expensive the stain the richer, more natural appearance it will provide.

To get a professional opinion about if your deck needs to be stained, what type of stain was used in the past and what type of stain is best for your deck call TruNorth Painting at 952-831-1433.