Hi, I am Scott Paul. I have been staining new and old decks for over 30 years. My Wood Filler help tips for decking are based on my history as a wood restoration contractor and actual hands-on testing. See here for more info about me.
Wood Filler for Decks: What Actually Works (and What Doesn’t)
Wood filler for decks is one of the most common mistakes I see homeowners make before staining. After 30 years of restoring wood decks, my answer is consistent: exterior wood filler does not work on deck flooring. It cannot handle the seasonal expansion, contraction, and foot traffic that deck boards endure. Even the best “exterior” fillers will crack, pop out, or discolor quickly. This page explains why, and what to do instead.
- Wood filler fails on decks because it cannot flex with seasonal expansion and contraction of boards, causing it to crack or pop out, often within the first winter.
- No exterior wood filler or caulk product blends with deck stain; it shows as white or off-color blotches regardless of brand claims or how many coats are applied.
- Small cracks and checks are normal signs of exterior wood aging and do not need filling; leaving them alone is always the better choice for deck boards.
- Board replacement is the only professional solution that guarantees a clean, consistent finish under clear, semi-transparent, or semi-solid deck stains.
- For severe damage, Ranger Patch by Gulf Synthetics is the only recommended epoxy repair product, but it still requires a solid color stain topcoat to hide the repair.
Feel free to leave me a comment or ask questions below.
Contents
- Why Wood Filler Fails on Decks
- Common Questions About Deck Wood Filler
- What To Do Instead
- Common Scenarios and Pro Fixes
- Prep and Finishing Tips
- Frequently Asked Questions
Wood Filler for Decking
Why Wood Filler Fails on Decks
Exterior wood filler is designed for vertical trim, doors, windows, and painted surfaces — not horizontal deck flooring. On a deck, boards expand and contract with every seasonal temperature swing. Filler doesn’t move with the wood, so it cracks, pops out, or crumbles, usually within the first winter. In climates with freeze-thaw cycles, failure happens even faster. Beyond structural failure, decking stains that show the wood grain will not blend with any filler product. The filler shows up as white or off-color blotches no matter how carefully it’s applied or how many coats of stain go over it.
White Blotches from Wood Deck Filler
Common Questions About Deck Wood Filler
What Is the Best Exterior Wood Filler for Decks?
My Pro Tip: There isn’t one. We cannot recommend any caulk or wood filler product for filling cracks in a deck. Using wood filler for decks will not yield a good result. Decking stains that show the wood grain will not blend with a wood filler. The filler will stand out and look like white blotches over your deck, regardless of brand or product claims.
Should I Fill Cracks in Deck Boards?
No, it’s best to leave small cracks as they are. They won’t harm the deck structurally, and any wood filler product will eventually fail anyway. Small cracks and checks are a normal part of exterior wood aging and do not affect the deck’s performance or longevity.
What’s Wrong With Using Exterior Wood Putty on a Deck?
The core problem is instability. Wood putty tends to crack or break out of the voids it fills when used on wooden decking, because it cannot flex with the seasonal movement of the boards. This is especially true in climates with freezing winters: the natural freeze-thaw cycle will cause wood filler and caulk to fail quickly. Beyond performance, outdoor wood filler simply does not look natural on a deck surface.
Can You Stain Wood Filler?
In general, staining over wood filler is not something we recommend. The filler does not absorb stain the way raw wood does, so it produces an uneven color pattern that stands out noticeably. If you do attempt it, sand the filler smooth, clean off all dust, and apply stain in thin layers. A solid color stain gives the best coverage, but even then the repair will likely show over time.
What Stain Covers Wood Filler?
A solid color deck stain gives the best coverage over wood filler, but no stain does a perfect job. A semi-transparent stain will not hide it at all. If your goal is a natural stained look, filler repairs will always telegraph through. Board replacement is the only way to guarantee a consistent finish when using clear, semi-transparent, or semi-solid stains.
What Can I Do About Deck Cracks?
My Pro Tip: Leave them alone. They are normal and will not harm the deck. The best approach for larger cracks is to sand around the area to lessen the size of the gap. In extreme cases, replacing or turning the board over is the better option. But most small cracks and splits will not hurt the deck’s performance and do not need any treatment.
What to Use to Fill Holes in a Wood Deck
For severe damage like a rotted knot, Ranger Patch by Gulf Synthetics is the one product I’ll recommend. It’s an epoxy-based repair compound that bonds well to wood and holds up better than standard fillers outdoors. That said, even Ranger Patch must be top-coated with a solid color stain or paint to hide the repair — it will not blend with semi-transparent or clear finishes. In most cases involving rot, replacing the board is still the better long-term solution.
Can I Use Wood Filler on Pressure-Treated Wood?
Pressure-treated wood is full of preservatives that resist severe cracking and damage, so cracking bad enough to need filling is unlikely. Regardless of the wood type, we do not recommend using wood filler on any deck surface, including pressure-treated boards.
I Have Cracks in My Deck Support Posts. Should I Repair?
No repair needed. Deck support posts are typically made of pressure-treated pine, and pine naturally shows surface cracks after a few years outdoors. This is completely normal and does not affect the structural integrity of your deck in any way.
What To Do Instead
1. Replace the Board
This is the professional solution and the one I always recommend first. Replacing a damaged board ensures uniform appearance across the deck and guarantees the new board takes stain evenly alongside the rest of the surface. It is the only option that produces a clean result under clear, semi-transparent, or semi-solid stains.
2. Epoxy Repair (Solid Color Stain Only)
In rare cases where board replacement is not possible, a two-part epoxy can stabilize rotted spots or corner breaks. The catch is that it must be top-coated with a solid color deck stain or paint to hide the repair. Never expect epoxy to blend with a clear or semi-transparent finish. Ranger Patch by Gulf Synthetics is the epoxy-based product I use in those situations.
Common Scenarios and Pro Fixes
| Problem | Don’t Do This | Pro Fix |
|---|---|---|
| Nail holes, divots, checks | Don’t use filler | Replace board or leave as-is — minor blemishes are normal |
| Soft or rotted wood | Don’t patch with filler | Replace board, or stabilize with epoxy and solid color stain |
| Large cracks or splits | Don’t caulk or fill | Replace the board |
| Edge rot or corner breaks | Don’t smear filler | Epoxy rebuild under a solid stain, or replace the board |
Prep and Finishing Tips
- Brighten after prep. Always neutralize the cleaner or stripper so new boards or epoxy repairs accept stain evenly alongside the existing wood.
- Check your stain type first. If you are using a clear, semi-transparent, or semi-solid stain, do not patch — replace the board. There is no filler product that will blend with those finishes.
- Blend epoxy repairs properly. If epoxy is used, sand it flush with the surrounding boards before staining, and plan on a solid color topcoat to hide the repair.
Frequently Asked Questions About Wood Filler for Decks
Does exterior wood filler work on deck boards?
Exterior wood filler does not hold up on deck flooring. Deck boards expand and contract with seasonal temperature changes, and standard filler cannot flex with that movement. It cracks, pops out, or crumbles, often within the first winter. In climates with freeze-thaw cycles, failure happens even faster. For any deck surface that will be stained with a clear, semi-transparent, or semi-solid finish, filler repairs will always show as discolored blotches that no amount of stain will cover.
Can you use wood filler on a deck and then stain over it?
You can try, but the results will be poor. Wood filler does not absorb stain the way raw wood does, so it will always appear as a different color or texture than the surrounding boards. A solid color stain gives the best chance of hiding a repair, but even that is not guaranteed to look consistent over time. Semi-transparent and clear stains will not cover filler at all. If appearance matters, replace the board.
What is the best wood filler for exterior deck repairs?
For the rare cases where a repair is necessary and board replacement is not an option, a two-part epoxy is the most durable choice. Ranger Patch by Gulf Synthetics is what I use in those situations. It bonds well to wood and holds up to outdoor conditions better than standard fillers. It still requires a solid color stain or paint topcoat to hide the repair, and is not appropriate under any transparent or semi-transparent finish.
Should I fill cracks in my deck before staining?
No. Small cracks and checks are a normal part of exterior wood aging and do not need to be filled before staining. Filling them with any standard product will create more problems than it solves. The filler will fail within a season or two and leave behind a worse-looking surface than the original crack. Sand around the area to soften sharp edges if needed, and stain right over the minor cracks.
Why do exterior wood fillers say they work outdoors if they fail on decks?
Exterior wood fillers are designed for vertical surfaces like trim, door frames, window casings, and siding — areas that are later covered with paint and do not experience the same foot traffic or moisture exposure as a horizontal deck surface. The “exterior” label means the product can handle some weather exposure, not that it is suited for a deck floor that flexes, gets walked on, and cycles through extreme temperature changes every year.
What should I do about a rotted board on my deck?
Replace it. Rotted wood has lost its structural integrity and will not hold stain, fasteners, or any repair compound reliably over time. If the rot is limited to a small section like a single knot, a two-part epoxy like Ranger Patch by Gulf Synthetics can stabilize the area temporarily, but it must be covered with a solid color stain and monitored closely. For anything beyond minor surface rot, board replacement is the only professional solution.
Need Help? Wood Filler Deck Questions?
Want Help? Please ask me below if you have questions about my deck tips with a wood filler or need help choosing a stain. Just post a comment below and include as much information as possible.
I am so grateful for this website and for your frank, clear answers to questions I’ve had for years. I’ve tried wood filler before- epic fail. You are spot on. I will say that I used Gorrilla Glue for a huge, deck splinter a few years ago and, while not ‘pretty’, most people don’t notice and it is still working fine.
New 5/4 weathershield deck. I would like to fill few knot holes before applying a semi transparent stain. Do the same rules apply as I read in your article? Or is there a product you can recommend to fill holes only? That will accept semitransparent stain. Thanks
Same rules apply — wood filler and semi-transparent stain are not compatible. A penetrating stain works by soaking into the wood, and it will not tint the filler, so any filled knot holes will always show as off-color, patchy spots. There is no filler that will absorb a semi-transparent the way the surrounding wood does. Our advice is to leave the knot holes as-is; they are normal in decking and blend in far better once the whole deck is stained than a filled spot ever will. If this is brand new pressure-treated wood, also make sure it has weathered before staining and test your color on a board first. https://www.deckstainhelp.com/how-long-should-you-wait-to-stain-a-new-deck/
Just curious, can you apply a colored resin to knot holes in the wood just for something different to smooth it out or will it make it rot the knot hole quicker in treated deck boards ? Kinda like putting marbles in holes in privacy fence . Just a quirky look
It will not work.
I have a 30 year old deck that is due for a re-coat of solid stain. There are some insect bore holes I’d like to eliminate if possible.
I get that filler is a bad idea, but could I drill them out to make them round and to expose fresh wood, then plug them with pine dowels? Titebond III Ultimate glue is waterproof and stronger than the surrounding wood so would seem suitable, but would it be better to use no glue and make sure the dowels are a tight, hammer-in fit?
Yes, you can do this, but it would be best to use pressure-treated dowels if they are available.
Saw some contractors recommend Silverback Epoxy to fill deck post cracks or splits. The posts are solid, but worry about further splitting if I don’t fill and seal the splits. Was considering using the epoxy before restraining the deck and posts. Are you familiar with the Silverback Epoxy and if it will accept stain like the manufacturer says. I’m in East Tennessee.
Thank you!
We are not familiar, but we doubt it will stain to blend. Let us know if you use it and it works.
Confused here……I have a weekend project coming up for my girlfriend’s pressure treated deck that has multiple places where the wood is cracked/split/splintered. I had planned to replace the really bad boards and use either Bondo or Minwax wood filler for the others that weren’t as bad, then sand and stain with solid color. Your advice Scott is NOT to use wood filler. Alas’s comments (below) contradict that, as he said he used wood filler and it’s stood up well for 14 years. I want the deck to look nice but don’t want to waste time and effort.
It doesn’t work well in every case we have seen or tested. It may have a lot to do with weathering. If we are in a cold weather state (we are in Michigan) where it freezes, we would never use it, as it will fail.
I put down a half inch treated tongue and groove porch even though the boards sat in the shed for two years after installation they shrunk and left a gap between each board. What is the best filler for that gap?
You cannot use wood filler on exterior decks or porches, especially in gaps. It will not work.
Can we cover up screw dents with wood putty on our newly installed patio? And stain it after! Contractor went overboard with the screws…
No, it does not work as explained in the article. It is normal to have screw holes on a deck.
Thank you for your speedy reply! Will have to get used to it!!
My pressure treated deck handrail posts have vertical cracks. I am concerned about rain getting in and rotting from the inside. Shouldn’t I fill the cracks or maybe try to get somekind of sealer inside?
No, leave as is. It is normal and not an issue to have cracks with exterior wood decking.
Have large chips at eyes. Big enough if you catch right barefooted can cut you. What can I use to fill? Or should deck company replace any boards like this?
Replace the boards.
the 2×8 top rail on my exterior deck has separated about a1/4″, what can i use to fill it in?
Fillers will not work or exterior decking.
Love your page Scott and thank you for this service!
OK so we have painted deck and the last time it was painted they did a terrible job and painted way too thick and didn’t allow proper drying time, etc. We are redoing it and looking to make it decent – not perfect.
We rented this sander and it’s going an OK job – we wish it could get more off but I think that if it were more intense then the exposed nails (or like all of the nails) would be an issue so doesn’t seem feasible. Also we have no problem replacing bad boards – they are pressure treated and we even have some left over from the last time ~3 years ago and they are ready to go
Anything else to keep in mind?
When reapplying a solid stain or paint, you want to remove all loose and peeling coatings. You do not have to remove the intact coating that is not failing fully: https://www.deckstainhelp.com/how-to-reapply-a-solid-color-deck-stain/
For sanding tips, see here: https://www.deckstainhelp.com/how-to-sand-your-wood-deck/
Use deck screws. We do not suggest wood fillers on decks. We never use primer on decks. We do not ever use paint on decks but solid color stains. Paints will have a stonger chance of peeling.
I’m planning to repaint my moms wood deck, but should I treat it with something after a thorough cleaning and sanding?
No need.
I’m redoing our deck. The wood, under 3-4 layers of paint, doesn’t look to bad to me. My wife really likes the look with the paint partly on the wood too. My question is what would be my best option for keeping the paint partly on and treating it. I am leaning toward Penofin oil for treated wood. It’s a covered deck but still gets a little wet. Please tell me what you think
Thanks,
Lee
It will not work to have the paint partially on. The paint has to fully come off if you want to use any semi-transparent stain or any treatment other than a paint coating.
FYI, Penofin has issues turning dark or even black.
https://www.deckstainhelp.com/?s=penofin+reviews&post_type=post
Does drylok work with wooden deck? Our deck is 10 years old with deep cracks on the supporting columns. Our contractor suggested 1 layer coating of drylok to fill the cracks and waterproof them from further water damage. The deck is solid dark brown color now. Thank you!
No, this will not work.
my deck has splinters
,i was wondering if i could sand it and seal it,rather than replace it
Depends on the wood condition and whether it can be salvaged or not.
Attached is a picture from my previous question
I am replacing old wood on my deck. The joists have some splits about 1/2″ deep and small old holes that are soft/turning black. Before replacing planks – I am thinking of spraying some boric acid to prevent any rot; and filling cracks and old holes with a loctite PL MAX construction adhesive to keep water from pooling in the voids. The loctite product appears to be very strong and used in marine applications. Any thoughts?
Not sure how it will work it will not “stain” to blend, if that matters. The boric acid will not stop the rotting where it has already occurred, so replace those joists or posts as needed.
Hi
I have wood beams on my front and back porch. Some of the beams have long cracks in them
Im not sire if they are natural of have been caused over time by the weather.
Someone suggested i fill in these cracks with wood filler. Before doing so i wanted to ask your opinion. I have attached a pic
No, do not fill them. They are not an issue and they will not stain to blend.
Thank you in advance.
1) 45 yr old deck exposed to extreme temperatures and snow and apparently multiple attempts painting it. Most has peeled from floor but posts have cracking and peeling paint. Want to remove rest of paint and protect wood. What is best approach? Sealing it? Waterbased or oil based stains best? Want to insure against future peeling!
2) Paint has peeled from very old, dry wood exterior window trim. Would solid stains work better than frequently re-painting? If so, waterbased or oil?
Thank you in advance. Have received many suggestions with little agreement.
1. Post pictures for prep advice.
2. Not sure on paint for windows, we only work on decking.
Painting contractor here. In answer to your second question: If you can avoid painting anything outside, do it. Yes, stripping the paint from your exterior window trim and coating it with a solid stain (oil base or water-miscible oil) will make future maintenance much easier. The stain will not peel.
Have a screens in deck . The screening is framed, there is a gap between one of the uprights and the screening. Just had the deck refinished and the new contractor says that he can’t recaulk the space. Any suggestions?
You can caulk it. Not sure why he would say otherwise.
New composite deck has dark marks from filler that was used ,how can I get rid of it
Sorry but no idea as to how or if you can.
For this 40-year-old, no maintenance
de ck should I use oil base primer?
And oil base stain and paint?
I am new to all these. Thank you for your help.
Do not use a primer with deck stains.
Best website ever.
My deck is 40 years old, lack of maintenance. Lots of rotten wood. But base is good. Have rotten knots too and big holes. What to do?
Use wood hardener?
Use primer?
Can I use primer over some leftover paint from five six years ago?
Then stain?
Then paint?
Please recommend brands too.
Appreciate your advice and time.
Thank you
Post pics in the comments for prep help and advice.
Attached are four. More to come
You should replace all our bad wood and rotting boards now as they cannot be fixed. Let the new wood weather until Fall after install. Prep and restain all with a solid color stain.
https://www.deckstainhelp.com/how-to-reapply-a-solid-color-deck-stain/
and
https://www.deckstainhelp.com/what-are-the-best-solid-color-deck-stains/
Permafill by Gulf Synthetics is discontinued. No longer available.
MANY EPOXY FILLERS STATE THEY ARE STAINABLE. ARE YOU SAYING THIS IS A LIE?
Yes. They will stain to blend with interior stains but not exterior transparent or semi-transparent stains.
Hello,
I have pressured wood on my deck. The previous owner had painted the deck and it has peeled off, there is also algae and some mold.
1.Can I just sand the deck?
2 I want to use a black solid stain, is a brightener needed?
3. There are some stains that have sealants, can I use that or do I need to use a specific waterproof sealant first and then stain it?
4.In one of the panels, the end is lifted, just used a screw?
Thank you for your time.
1. You can sand off the paint.
2. Clean and brighten for final prep after.
3. You cannot apply a sealer before applying a solid color deck stain.
4. Not sure what you are asking.
So Bondo and or pro bond by Elmer’s you claim is not needed for deck repairs do nothing is your opinion. Their claims are what false?
Their filler will not stain to blend with a transparent or semi-transparent deck stain. It will look like white blotches all over your deck under the stain where you use it. They also have a tendency to crack and break out if used in a state where it freezes.
Scott,
Regarding filling knot holes etc., the guy at the store suggested epoxy. No disrespect; but I had to ask.
Thanks!
Mark
Epoxy will not stain to blend. You can find a caulk that is similar in color to your stain and use that.
I read the same thing youtube
In one breath you say you can’t recommend a filler in the article, In the next breath you’re recommending Permafill by Gulf Synthetics (which they no longer sold BTW) in the comments. Sounds like you trying to sell a service to me.
Huh? Feel free to go elsewhere for advice. Thanks
I have used woodfiller for last three years on my deck and I have found the woodfiller has lasted for a year or more,I have painted the deck after I did any scrapping and sanded it .
I have a new deck that has cedar posts and beams that were assembled with Simpson “concealed” connectors. But those require 5/8″ holes where the steel pins are driven into the internal connectors. My plan was to use a plug cutter to make plugs out of the same wood to cover the holes, but the holes don’t have pristine edges. I was thinking about filling them and sanding them flush until I found this article. Any suggestions? Unfortunately, the stain we’re using is oil-based and transparent.
Fillers will not work to blend when stained. Maybe a pre-tinted filler or caulk that is similar in color to your stain will work.
Thanks for the reply.
Right this second, I’m trying an experiment of the old trick of glue mixed with wood sawdust.
Perhaps the thing that will help is that the holes in question are either 9′ in the air or down by my ankles.
Hi there. This is all really helpful, especially seeing that the vertical cracks are normal. Here’s where I need some reassurance: I live in a place where we get ice in the winter. I kept thinking I needed to fill the variety of cracks so that the expansion of frozen water within those cracks would not worsen the condition of the wood. Is that a concern or are you saying no, it either won’t do much damage or it will do damage but there’s not much to be done about it and eventually replacement would just have to happen? I appreciate your time. Thanks so much.
Cracks are normal so just leave them as is.
We had a new deck installed in November 2021 (we live in Georgia). The wood is pressure treated and it now has long cracks down the posts some of them look deep. There are some cracks on the deck boards as well. What should we do?
Nothing. Cracks are normal in decks. Just leave it as is. See here about new wood and staining: https://www.deckstainhelp.com/how-long-should-you-wait-to-stain-a-new-deck/
Even when it looks like this?
Yes, that is normal.
how can I restore this deck?
Pictures?
HI there, May I ask what you mean that the wood filler will fail? Does fail mean cause rot of the boards? Or does it mean the filler will get dry and come out? Is the concern that using wood filler to repair cracks will look “ugly” under transparent stain or that using wood filler would actually damage either the boards (rot?) or make the paint job look bad or peel? Thank you!
All wood fillers will fail on exterior wood. It will “crack” or fall out after a year or less. It also will not blend at all with any deck stains that are transparent or semi-transparent.
Thank you so very much. If there was 1 coat of primer and 2 coats of paint on the wood, would you see the cracked wood filler? A company proposed filling the cracks with wood filler and then priming plus 2 coats of solid color paint on the deck (we also have three new boards that are clearly a different color). I am wondering why they would say that? Unless it makes the boards looks the most smooth and we would never see the cracked filler under all of the layers of paint? Is there ANY advantage to using a filler?
Eventually, if it comes out then yes, you will see it with gaps. BTW, you should never prime and paint an outside deck. This is a recipe for peeling.
Oh my goodness! Thank you! You mean skip the primer part??? Or do you mean do not use paint, just use stain??
No primer or paint. Use a deck stain. Solid color if you want the opaque look.
https://www.deckstainhelp.com/what-are-the-best-solid-color-deck-stains/
Any way to fill or hide those pressure-treated incisions? I plan on using a solid color stain. I just hate those marks!
Sorry but not really.
If I will be applying a solid stain (RAD) which type of product for filling cracks/voids is best (mainly for longevity)
Noticed a few answers here saying it’d be ok if using a Solid stain. Epoxy. Filler. Exterior caulk.
Would you apply prior to strip or after?
I have cracks as well as splintering on our 15 yr old PT pine deck.
If using a solid stain then use a flexible caulk to fill. After stripping.
We had a new deck constructed this summer. The contractor placed caulking in the joints of the rail top. Now I read that it should not be done! How do I get that off? sigh……
You probably cannot remove it. Stain the deck and if the caulk shows, you may need to redo the caulk over the current with a color that blends with the stain color you picked.
Found this website too late. Just used some wood filler on big cracks, stained deck with semi transparent product. Colour difference between filler and deck boards is atrocious. In two years, when I re stain, will switching to a solid stain mask it better? I could also just reverse the boards too I guess.
Solid stain will mask it.
Thank you for your feedback!
What can I use on the old boards before the solid stain is applied to fill in the weathered cracks? The replaced boards are obviously new and solid and I want them to blend better than they will as is; I’ve already purchased the solid stain it was mixed at Sherwin Williams.
It will not work. The filler will fail and crack out on exterior wood.
So, if not a filler, which was more a descriptive word I chose than product, is there anything that can be applied to bridge the visual gap between the 2?
Sorry but no.
What about a epoxy filler?
It will not stain to blend. If using a solid stain, then you should be okay.
My deck posts are showing such cracks as in the pic. My contractor recommended to apply this exterior coating before painting/staining. Will this help for cracks to stabilize and not propogate faster and is it generally recommended to apply on the floor of deck before paint/stain?
Deckover peels and cracks are normal in wood. Just leave as is.
Thank you v much.
I have one more followup: on this solid stained deck (6+ years old), I dont want to go through the hassle of sanding the entire deck to remove old stain. If the stain can be removed with a stain remover, I will go for a semi transparent stain, otherwise I will go for a solid stain.
Are the below recommended steps to follow before I pressure wash and start staining
Please advise if above are recommended or should I skip these two steps and move to pressure wash and staining.
You cannot strip this olid stain off so your options are to power sand it all off or cover it with another solid stain.
Thank you. I will go ahead and do another solid stain then.
This means that using the stripper has no value, correct?
Is wood cleaner recommended generally (even if there is no mold/mildew), before applying solid stain?
In this scenario, you do not need a striper. Just give it a good pressure wash.
And no wood cleaner as well? Thanks much!!
No need.
I have a main Cedar post on my deck that’s in concrete. It’s older and one side is chewed up due to a gate that was on it & pulled out over time. Can I add a thin cedar board over it? I notice some that are a 1/2 inch thick or less for indoor use.
Was thinking it might protect the holes from the weather?
Yes, you can wrap the post with cedar boards. This is very normal.
Thank you so much for your quick response! I have a follow up question…
Will any cedar board work or I’d there indoor & outdoor cedar? Is there a recommended thickness to use?
Use exterior cedar wood. 1″ is normal. They look like this when wrapped.
Do you recommend a particular brand of stain for a transparent or semi transparent stain? The deck has pressure treated flooring & cedar rails. It suffers from extreme sun during the day & weather exposure. Temps in the area range from high 90s to just below zero in the winter. The frame & posts are older. The railing & floor are brand new green lumber.
One of these brands: https://www.deckstainhelp.com/best-semi-transparent-deck-stain-reviews/
Great Help article. I was just about to attempt to fill small cracks in my deck boards with a wood filler. Glad I read this article first. I am just going to lightly sand the deck and re-stain with my transparent stain.
I completely sanded my 2 year old deck that had no paint or stain. I used Sansin wood stain and it turned out great.
It will be 2 years this summer since I stained, and there is like no peeling at all.
The only spots it has is where the boards end against a 2×10 on a ramp for wheelchair.
Is there anything I could put in the board end to prevent this from getting worse. Like an outdoor caulking etc ???? Thanks
It will not work well or stain to blend with the deck stain.
Dear Sirs
I have a moderately large treated pine deck , originally painted with a dark brown Wattyl Decking Paint (Weatherguard – I think). Probably painted about 5 years back. For some time now it is showing major cracking – some cracks quite long but none wider than 1 to 1 1/2 millimetres. Further painting does not cover the cracks which apparently need some type of a filler. External position with temperatures ranging from minus 7degrees C to about 34 degrees C. I would appreciate your advice as to the how and what with to fill the cracks.
Col Davidson
Crack fillers will not work for outside decking.
I have some deep screw holes and joints that separated on my deck in Maryland. Anything recommended to fill and take a transparent or semi transparent stain?
It will not work as the article above explains.
Thank you.
I did read the article, but was hoping for something…….
I bought all weather silicone that takes on paint, was hoping that would work. Guess I’ll take it back and live with the issues.
Hi, My 87 year old dad just finished putting in a new deck. He’s very meticulous and does good work. He sanded all sides of each pressure treated, heat cured board. Then he applied 1 layer of semi-transparent outdoor stain to all sides. He then applied a 2nd coat to the top of the board. 1 year later the boards are getting cracking that runs longitudinally. The cracks are about 1/4 in wide and some are up to 3 ft long. The knots are also splitting and cracking. He lives we in the Pacific Northwest with plenty of rain and snow.
So, is there anything he can use to fill these cracks so that they don’t worsen? Preferably the fix wouldn’t take back breaking work to accomplish. Thank you much!
No, it will not work or blend with the semi-transparent stains.
Hi my pool deck has slight cracks what should i use?
Just leave alone as is. A filler will not work.
Can I seal around base of my summer house/bar. With exterior silicone it’s on a slab base thanks
Not sure if that will work or if it is needed.
Should I fill screw holes in new summer house / bar with exterior wood filler before using clear stain
No, it will not work.
Thanks
We have just installed a new deck with pressure treated wood. Should I wait until next year to stain, to let the wood weather, or would it be better to stain it this season?
See here for new wood tips: https://www.deckstainhelp.com/how-long-should-you-wait-to-stain-a-new-deck/
Very helpful info on this site. Thank you!
I am planning to use Defy Extreme Solid Stain on my deck. I have some cracks that are unsightly and wanted to ask about filling those. Since I am using a solid stain I will not have the color matching issues of transparent stains. Would filling work intros case?
A solid stain will cover the wood filler.
Thanks. Any particular type that would be better for the job? Wood putty? Exterior painter’s caulk? etc.?
Exterior caulk is much more flexible.
Thanks
Hello,
I have a deck project were there are some severe cracks on the main support posts. They are long and deep. Since fillers and caulk are not recommended, what can I do to prevent these cracks from getting any larger over time after I redo the deck…?? As of now, the deck will be re-stained with a dark brown colored stain. Also, I have read that you should not use colored stain on the floor of a deck but instead you should use a semi transparent. Is this correct…?? The homeowner wants the deck all the same. What is the best way to stain the floor so it lasts for several years….??
You cannot prevent cracks from getting any worse. If they are bad, then replace those boards. If you want a semi-transparent dark brown then look at TWP in Dark Oak or Armstrong Clark in Rustic Brown. Penetrating stains like those will not be prone to peeling like a solid stain. Just clean and recoat every 2-3 years,
Unfortunately the cracking is on the main posts and not the floor boards. The deck has a lattice roof and would be virtually impossible to replace without excessive cost involved.
Thanks for the reply and info on the semi transparent
I have a deck board with removed splinters from a chisel. Would it be ideal to sand, then stain over those parts? Wood filler them? Or replace the boards? Climate is harsh winters.
Never use a wood filler on a deck when using a semi-transparent stain. Spot sand the areas, then strip all the deck down, brighten the wood, then stain.
I’m prepping a newer deck for eventual stain and have noticed what I would consider done deep or wide cracks especially in the 4×4 posts I installed. I know you mentioned no filler, leave as is and replace only if bad enough
What’s consider bad enough to replace? I’ve read 1/4” deep or wide…
That is not an issue. Just leave as is.
Thanks for the quick response. This is about 3 weeks after being built…looks ok?
No issues.
First time staining 1 year old redwood deck. Do I do anything with the knots, some are cracking and some small ones have fallen out. Is there something I can do to keep them from falling out? Will be using RAD cleaner and brightener and semi transparent stain. Thank you.
Wood filler will not work on a deck and it will not stain to blend. It will look terrible.
How. Do you repatr brick that the deck is joined to
I have no idea what you mean?
Have stripped and brightened a cedar deck, replaced some rotten boards, do those boards need to be left uncovered to weather or can they covered with clear plastic along with old boards until they can be stained? Is there a recommended stain to match CWF-UV cedar, don’t want to use CWF-UV again, was looking at TWP 1501.
Leave uncovered. TWP 1500 is much better.
Any suggestions for splinters on the deck? From the day it was built there seemed to be numerous amounts.
Try a solid stain: https://www.deckstainhelp.com/what-are-the-best-solid-color-deck-stains/
Hi, We have a pressure treated wood deck about 10 years old now and beginning to show its age with some minor weather cracking and discoloration. I pressure wash it (fan tip only) with detergent every spring so it is “clean” but there are still plenty of stains in the wood. I’d like to put on some kind of sealer to prolong its life and hopefully improve the look a bit. The wood is expose to extreme cold and lots of snow and ice so I am concerned it will just chip and flake and make things much worse. I’d be grateful for any suggestions and advice!
Try one of these stains: https://www.deckstainhelp.com/the-5-best-deck-stain-reviews-and-ratings/
What about taking elmors wood glue and mixing in saw dust of the type of wood you are trying to fill a crack, and making a putty to fill cracks or say spaces in shrunk treated deck wood?
Do you think that would hold up to the elements and possibly be able to be stained with the rest of my deck come the fall?
No.
What we use is construction adhesive mix with sawdust rub in cracks sand it
i have 4 x 6 supporting posts on my wood awning that have developed surface splitting( not all the way thru). what do you suggest to use on these splitting surfaces?. I want to stop any further progress of this condition. the posts and awning are about 9 yrs. old.
Splits are normal for exterior wood. Just leave them as is. No harm will happen.
What do you recommend for a knot that has started to rot? I see you don’t recommend fillers but worried to just stain this area like the rest of the deck.
Any help would be greatly appreciated!
See Permafill by Gulf Synthetics. It is not stainable with a semi-transparent stain but it will work to fill your issues with your stair stringer.
What stainable product would you use to fill cracks on a deck in Maine that is exposed to extreme heat & cold?
Nothing will work like the article states. Leave the cracks as is. It is normal.
The top rail in this photo has been curing for 8 months and we are now ready to stain deck- photos show what happened to board over winter. If filler is not suggested, do you have any suggestions as to what should be done? Thanks for your time and great website!
Just leave alone or if really bad, replace the board.
Thanks 4 your response, hoping pics went thru. If we replace board do we wait several months to stain or stain now with the rest of the deck? Thanks again!
You could stain the new board now and then apply another coat to the new boards in the Fall.
No pics.
my contractor filled screw holes on the deck and railing with wood filler then sanded the areas. I wanted to stain it natural, but now not sure what to do as I’m concerned these wood fill sections will be very noticeable. Should I sand the whole deck and railing to even it out then prep treat it before I stain? Would changing the stain color to a darker shade help?
It will be noticeable and it will not blend with the stain. Sanding will not help Doesn’t matter the color. He should not have done it and there is not an easy way to fix it.
Building a new deck. Should anything be done to the knots in the wood before staining deck?
Nope. Just leave them as is.
Hello,
We have an old (likely since the house was built in 1990) untreated cedar deck, with some rot and/or softer spots on its boards.
1.) Would I be able to use PC-Petrifier Wood Hardener on some of its boards and railings? (I wouldn’t mind using on all of it.)
2.) If so, should I use it after I would clean and brighten it?
3.) I’d like to just seal it afterwards (and yearly from now on). What would you recommend as the best sealer for this type (age & condition) of deck? We live in Seattle, and even though the deck is facing west, it gets max 3hrs/day of sunlight.
Thank you very much!
Larry
1. Never used this before but it seems like you can.
2. Prep first.
3. TWP 100 series in clear for a sealer of the Defy Extreme Clear.
I just put new decking boards on my deck, Looks really good but a lot of nail holes, I would like to fill them and stain the deck clear, question is there any filler that would look like treated wood ? so when I put the thompsons clear on my eyes won’t go right to them ? Thanks Glenn
No, it will not work on outside wood.
I know that wood filler and caulk aren’t good options for filling cracks on deck but, I have a toddler and I’m concerned about splinters. My deck was in bad shape when we moved to this house and I have sanded it down so it’s a flush surface again. I still have cracks and some deep chips. If I just paint my deck is there anything I could use to fill the bad areas? I would replace some of the boards but it would end up being more than half the deck and I can’t get into that big of a project. Please any help you can offer would be greatly appreciated
Try Permafill by Gulf Synthetics.