Should You Stain the Underside of a Deck?

image of a deck but Should You Stain the Underside of a Deck

Most deck owners, when installing or renovation their decks, pay so much attention to the visible parts and disregard the underside. Well, first impression matters and that’s why they stain the top surface only. However, is that enough to protect your deck completely? One question you should ask yourself is, should you stain the underside of a deck? 

Well, you don’t have to necessarily stain the underside of a deck. The primary purpose of staining is to offer protection to your deck against environmental elements such as exposure to direct sunlight, which causes discoloration. The decks’ underside sees no direct sunlight; therefore, it is not a must that you stain.

If you want to know that you don’t have to stain the underside of your deck, then go ahead and remove one board of your deck and look at the underside of it, you will find it as good as new. 

Much as you may not have to stain the underside, it comes with risks as well. Since there’s no sun on the underside, it may become a breeding ground for mildew and molds. Staining the underside of the deck, therefore, will prevent the growth of molds and mildews.

Should Deck Boards be Stained on all Sides?

It makes every sense if you choose to stain only the top side of the deck as it is exposed to the sunlight and rain, making it the most susceptible to damage.

However, you might have your reasons for staining all sides of deck boards for aesthetic reasons, especially on the upper-level deck.

Do I Need to Remove Old Stain Before Restaining a Deck?

If, by chance, the stain on your deck is old, weathered, and peeling, it would help if the first thing you do is remove all the stains. You can use paint strippers to remove the old stain on your deck.

Solid-color stains are great at protecting the wood decks given them amazing looks when new, with time, the stain will flake and fade as it can happen on any stains.

Benefits of Under Deck Stain

You don’t need to stain the underside of the deck, but that does not mean that you cannot stain it at all. If you have a two-story deck, for example, you should try as much as you can to maintain its underside. Here are the three significant benefits of staining under-deck:

It gives your deck a boosted lifespan. Wooden decks with two-story tend to be more vulnerable to weathering compared to the smaller, one-story types. Therefore, the staining of under-deck helps to lock out moisture as well as to preserve the strength of your deck.

It gives the Deck Upgraded looks. Usually, you will find that the underside of a two-story deck attracts a lot of molds, different stains plus wear that don’t necessarily appear on the topside. Therefore, under-deck staining is excellent and will keep the hard-to-reach spots of your deck in excellent condition. 

It makes the Deck Repellant Pests. Pests also know how to go about their businesses and are likely to target the wood’s unstained parts. In the process, these pests end up damaging the strength as well as the aesthetics of your decking. 

Staining, especially these hidden parts are great at reducing the risk of occurrence of pest-related deterioration and help preserve the strength of your wooden structures. In case you notice damages on your deck that might look like pest-related, consider calling the pest control pro for more insight on the subject.

Staining your deck is no simple task, and the frustration and disappointment that occur when the project comes out poorly can be overwhelming. One of the more common failures that you can experience is that the stain, whether semi-transparent or solid color, begins to peel away. To avoid the problem, you first have to understand the cause; let’s start there. 

What Causes Deck Stains to Peel?

You must have noticed the stain on your deck peeling and wondered what might be the cause. As much as this might be common, two fundamental reasons explain the peeling of the deck stains. These reasons are:

  • Over Application of Stain

If you have stained a deck or any wooden structure before, then it should be obvious that too much stain over the surface of the wood does result in the peeling of the finish. Deck stains, specifically the semi-transparent ones, perform poorly when you apply several layers.

Therefore, each time you are doing the staining work, ensure that you only apply enough formula for the wood to absorb with ease. Why is it so? Well, the wood takes in moisture from rain as well as the snow. When the sun shines and in turn dries the wood out, the moisture vapor from the wood looks to escape the wood by passing through the stain. Too much stain prevents the vapor from escaping into the atmosphere; these levels the stained layer with one option-to start peeling off.

This problem is more evident during the springtime when the deck now starts to dry out following the winter moisture.

  • Poor Adhesion

This problem is also a common cause of peeling in wood stains. When the stain fails to adhere correctly to the surface of the wood, it will start peeling off. You will notice that little impacts or maybe water coming to contact of such surfaces would lead to peeling. 

Therefore, you should always ensure that you prepare the surface properly before you stain to minimize the peeling’s chances.

Alternatively, you can use high bonding primers to help increase the adhesion between the wood and the stain.

Watch this video on how to stain a deck:


The deck’s underside sees fewer activities; it does not receive direct sunlight, rain, or traffic and can stay for an extended period without calling for maintenance practices such as staining or sealing. Even so, 

Should You Stain the Underside of a Deck?

I believe, at this point, you are aware that you do not necessarily need to stain the underside of your deck. However, it does not mean that you can not stain it at all. If you are looking to prevent the possible growth of molds and mildews or even pests that staining would be a good move.

Thanks for taking the time to read this article. I hope you found it helpful. If so, kindly let me know what you think by sharing your thoughts on the comment section below.

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Tyron Otieno

Tyron is an avid woodworker and writer. He founded this website to help other woodworkers, whether hobbyists or professionals by sharing his knowledge and experiencie after a decade of woodworking.

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