by
Russ Vanover
| Jun 15, 2017
By Jim Coshow | Article originally posted on Dunn Solutions
One thing I have learned over the years is there is a lot more to staining (or restaining) a wood deck than most people think. One of the biggest errors we hear about is people staining new wood decks without properly cleaning them first. That makes sense, right? "I bought new wood from the local lumber yard, so I should just be able to sweep or rinse it off and be good to go!"
Unfortunately, the new wood you bought has been through quite a journey. From the mill to the distributor, then by truck to the lumber yard—wood gathers dirt and mold spores from multiple environments as it passes through each leg of its trip. That is why hosing off the sawdust and visible dirt is just not enough.
Many people get away with skipping this critical step, and for that we are thankful. Others, however, can be stuck dealing with mildew growing beneath the coating they just applied or may see areas where the penetration or adhesion of their coating is less than ideal. We created this article to review and clarify some of the key steps to consider so you can have the best possible chance of your deck finish performing as expected.
Allow New Wood to Dry
Although it's tempting to skip this step, start by allowing new wood to properly dry (or season) before applying a stain product. Proper dry time is anywhere from 4–12 months, depending on your area's climate and weather. It's ideal to allow the wood to season to a 15% or less moisture reading. The seasoning process goes a long way toward helping prepare the wood for accepting the stain product. The results are worth it!
In Every Scenario, Clean Your Deck First
From clean-looking decks to surfaces caked with dirt, you will never create challenges by doing an extra cleaning—but skipping this step could lead to trouble! Remember to read the cleaning instructions, which will help you take the right steps to protect your plants, siding, and hardscapes. After a thorough cleaning, be sure to evaluate if your deck could benefit from an application of wood brightener.
Preparing Your Deck Surface Means Avoiding "Mill Glaze"
Mill glaze is a controversial subject. It's a condition referring to smooth lumber which is not receiving stain or paint and is certainly worth guarding against.
A simple water test and proper preparation of the wood will protect against this condition, as long as you do both before the coating is applied. To test for this condition, simply apply water to the area and let it sit for a few minutes. If you see the water beading up and failing to penetrate, you'll need to address the issue. If you're seeing signs of mill glaze, you'll want to use a wood brightener on your deck lumber, followed by a light wash and thorough rinse. Then allow for a proper dry time of 24-48 hours before applying your coating.
We share more about mill glaze in part 3 of this series.
When Is Your Deck Dry Enough to Stain?
In general, you want to wait one to two days after cleaning your deck to begin the staining process. Should you have rain, you will want to wait another one to two days before resuming the project. If your deck does not get any direct sunlight, it is likely to take an extra few days to dry out properly after wet weather.
Staining your deck before it is completely dry runs the risk of trapping moisture that could lead to mold or mildew challenges. Consider using a moisture meter to help you determine if your deck is dry enough for staining to begin.
Be Mindful of Temperature and Weather
Many deck stain manufacturers say their product works best when applied in temperatures between 60–80 degrees, but shouldn't be applied in conditions below 50 or if the temperature drops below 32 degrees within eight hours. Do not apply your deck coating if rain is expected within 24 hours. A quick light rain is not likely to harm the finish if it has already been absorbed properly, however a heavy rain will most likely ruin your finish, requiring you to strip it all off and start over.
How Often Should Your Deck Be Restained?
This is about personal preference to a large degree. If you want your deck to look like a piece of furniture, apply a maintenance coat every six months—remembering to first clean the deck surface every time a maintenance coat is applied. A light cleaning will usually be adequate if you stained your deck within the past 12 months. If it has been more than 18 months since the last application, a heavier cleaning will most likely be required.
If you are switching to a different brand of deck stain, check with the manufacturer for any steps needed in addition to cleaning your deck. Changing stains during maintenance applications may require that you strip off the old coating and start from scratch.
General Tips for a Quality Result
- Don't apply your deck stain in the direct sun; choose morning or evening hours, or a time of day when your deck has shade.
- Morning application can be a safer choice to help avoid any contact with dew that sets in overnight.
- Don't apply more stain than the wood can absorb. Over-application is the most common problem people experience. More is not always better, and puddling stains can turn into a gummy mess that will create hours of additional work to rectify.
- Work in small areas, keeping a "wet edge" as you go along. Consider staining the entire length of one to three boards before moving on to a new section.
- Wipe off any excess stain after allowing the recommended time for penetration.
- Should you do any sanding of your deck surface, make sure that the dust is completely removed before applying your stain. This is especially important when working with hardwood decking.
- Be especially careful not to sand the heads of your nails or screws, which removes the protective coating and causes additional challenges.
- When sanding, it is recommended that you don't use anything finer than 80-grit sandpaper for hardwoods, or finer than 100-grit for cedar.
- Refer to the manufacturer's instructions for the specific dry time and curing time before walking on your deck or putting back furniture, barbecues, and other accessories.
Notes on Safety
- When done with your oil-soaked stain rags, it is important to handle them properly before disposal. Lay them flat on the ground in single layers to dry fully. Be sure to check out this helpful tutorial from Dunn DIY for more information.
- Spreading oil-soaked rags out on a drop cloth will limit the chance of any damage to concrete or hardscapes and help protect your lawn.
- Once the rags are stiff and dry, you can dispose of them with your local waste management company or landfill.
Skipping the recommended steps when finishing or refinishing your deck is certainly a gamble. We hope you take the time to do it right so that you can enjoy the beauty and performance that can come with a job well done!