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Fixing Cracks in Porch Posts

WoodLess's picture

Hi - New to Breaktime.  I need some expertise on how to repair cracks in the posts on my porch.  The house is a 100+ year old Victorian and some of the posts have vertical cracks in them about 1/8 inch in width.  What is the best way to seal these to keep water out and prevent further damage from freezing during winter?  I don't know if a silicon caulk or a hard wood filler would be best.  Any advice most appreciated.  Thanks.


(post #75056, reply #1 of 12)

Bondo works well on posts. Really work it into the cracks.

Chuck S

live, work, build, ...better with wood

live, work, build, ...better with wood

(post #75056, reply #2 of 12)

Whatever you use, DO NOT use silicone if you ever want paint to stick again.  Scrape and brush with a stiff brush to remove loose paint and dirt.  Assuming these are just surficial cracks, and not deep structural cracks, you should prime any bare wood first, then patch the cracks with any decent, exterior grade wood filler or patching compound (then prime the patches before final paint).  Personally, I like to use painters putty (DAP I think) for patching small cracks, it stays somewhat pliable, but it must be primed with oil based primer.

(post #75056, reply #3 of 12)

Are these solid posts or laminated round wood columns?



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(post #75056, reply #4 of 12)

The posts are solid wood, likely original to the house.


(post #75056, reply #5 of 12)

So this is checking in the grain of the wood. Bondo or minwax wood filler.



Welcome to the
Taunton University of
Knowledge FHB Campus at Breaktime.
 where ...
Excellence is its own reward!



Oh Well,

We did the best we could...

(post #75056, reply #6 of 12)

Please continue, I have round laminated posts with cracks?  Thanks

(post #75056, reply #7 of 12)

I have four tapered round columns of the same vintage that were recycled and will be used on my porch in the Spring.They had the same issues that you're experiencing.

I like to use Abatron 2 part wood epoxy for exterior repairs .It is easy to use,lightweight,sands like a dream,doesn't shrink.

It's a little costly but i've used it for a long time with great results.

(post #75056, reply #10 of 12)

With that sort of column, there are usually two things going on.

The glue joints are failing. To fix that, I get out my strap clamps. You can get a set at walmart or some auto parts stores as tiedowns for about forty bucks for a set. I have a couple hundred bucks worth, but the set of four can probably do a column at a time. I make sure there is no debris or pain in the cracks sometimes running a folded sheet of sandpapre up and down a few times into it. Then I use the compressor or the exhaust side of a vacumn to blow the dust etc out. This is all to make sure there is a good bond.
Then I take some glue injection needles ( think giant hypodermic) and get glue in the cracks, then wrap the straps and cinch it all up tight. The choice of glue - should be able to handle exterior and should give a long working time. I've used both Titebond II and Gorilla Glue.
After thjat, some minor cracks may still show. I finish off with the minwax wood filler and sand it all smooth after removing some residue with a sharp scraper.
Then new paint.

The other thing going on often - what caused this cracking - is that these columns are hollow in the center. They need to be installed to allow ventilation from bottom up through to the top. Instead, they are opften installed with glue and caulk sealing them up tight at top and bottom, trapping moisture and heat.
The result of this is that the wood staves expand and contract too much, the movement stressing the joints and bringing on the failures. It is important to install with instructions followed to a T, but one solution I have seen is to use a hole drill to drill for inserion of those little 1-1/2" pop-in vents in less noticeable sides of the column.



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Taunton University of
Knowledge FHB Campus at Breaktime.
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Oh Well,

We did the best we could...

(post #75056, reply #11 of 12)

Thanks Piffin.  Mine are about three years old, and no serious cracks yet but out of 9 posts a couple do need attention.  Had doubts when I bought them but was in a pickle and had to have them quick.

Colums cracks (post #75056, reply #12 of 12)


I read your advice and found that my colums are hollow and I found two Walmart size bag of birds nesting in it. 

As per your advice, I clean the column and fill some glue between the cracks. I couldn't find the strap clams so I try to use the plastic tie, and while the test tie my column move a little from the bottom, and I realize it is not fixed to the ground. And one question comes in my mind that do these columns support or holding the roof or they are just for show. 

One more question, please 

When I was tightened the tie, it pushing the wood strip little more in from its original joint mark. 

I am attaching the picture of my columns and the thing I purchased to fix it.  Please advise how I can get the best results. 

Thank you 


sorry I I don't know how to attach more than one picture 

IMG_0822.JPG1.72 MB

(post #75056, reply #8 of 12)

I've used Bondo (auto body filler) on porch posts.  They also sell a general use version at home stores.  Be aware though that it is not the easiest thing to work with in this kind of application, the main reason being the short working time before the stuff starts to set up.  It took me at least a few "coats".  I got near perfect results after some sanding.

Definitely don't use silicone caulk for the reason mentioned above.  Further, I don't think any kind of caulk would work very well as it will not be sandable and many caulks shrink.  It would give a very unprofessional look to the job.

Edited 11/29/2006 7:13 am ET by Matt


(post #75056, reply #9 of 12)

I would avoid caulk too.

And I second the recommendation for Abatron products, which are specifically formulated for wood. WoodEpox is their product that would be applicable here:

Here is another wood epoxy that will work well for your posts:

Some have had good luck with the automotive products like Bondo, but I have not. The two mentioned above are designed to work with wood, so they expand/contract at similar rates. Besides, they are a much easier to work with and sand easily.

"It is what we learn after we think we know it all, that counts."

John Wooden 1910-

******************************************************** "It is what we learn after we think we know it all, that counts." John Wooden 1910-2010