This post was updated on May 1, 2024
Your Deck is not a hardwood floor and should not be shiny or excessively sanded smooth.
We have had people write in and ask if they should apply polyurethane to an outdoor deck. The notion of having a beautifully shiny, smooth finish like an indoor wood floor on your outdoor deck may seem appealing to some of you, but it is not practical. You should not apply polyurethane to an outdoor deck surface for several reasons. Rain and harsh UV rays from the sun will penetrate the polyurethane cause it to fail quickly, leaving the wood susceptible to weathering. The polyurethane will eventually blister and peel on exterior wood. Those who have experienced a peeling or blistering deck know how much of a nightmare it is to fix, as heavy sanding will be involved in the removal.
Peeling Deck Varnish Year Later
For an outdoor wood deck, the best finish penetrating is a semi-transparent stain. The best prep is using proper cleaners, strippers, and brighteners. Sanding a deck reduces a stain’s ability to soak into the wood grain. If you sand your deck to a completely smooth finish, the stain will not soak in, and peeling may occur. For this reason, it is best to leave the surface slightly rough with some natural texture for the best results.
Remember that your deck is not a hardwood floor. It should not have a shine or be over-sanded.
Do you have any input on this subject? Comment below.
For more info, see our Deck Stain Facts section with over 150 simple Q&A articles that answer all the questions that you have regarding deck staining, cleaning, and prep.
If my deck is partially shinny, what should I do before re-coating?
Remove the current coating.
Post pictures if you would like help with removing.
Can you use and epoxy on a deck to make it shine and to reduce shoe prints? We used a solid stain and it is very flat and shows shoe prints. This deck is at the beach.
No. It will fail on a deck.
Hello,
I have a about a 1 month old deck.
We used premium pressure treated 5/4 decking from Lowes.
I also live in Florida across the street from the ocean.
We have one of the highest salt contents in our air in the country.
We like a natural looking wood finish.
Which of your product do you recommend to prep and then seal or deck from the salt and UV rays?
PS.
I am ready to buy now.
Too early to stain. See this for new wood tips and stain suggestions: https://www.deckstainhelp.com/staining-a-new-deck/
Is there any mild, slightly shiny polish I can apply to the stained deck, sort of to “recondition it” a bit and give it just a touch of shine?
No.
I watched an episode of “This Old House” in which one of the suggestions was not to apply a varnish over the top of a stained deck, but to mix some into the stain itself before applying.
Is there any benefit of doing that? Any contraindications?
You cannot add a varnish to a stain. It will ruin the stain and void the warranty. That is bad advice.