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favabeans5

cedar fence posts in concrete

favabeans5
12 years ago

Hi,

I know this isn't a fence forum but thought some of you might have a perspective on my question.

I am planning to install a cedar fence and us cedar fence posts. We can some pretty high winds around here and I am planning for a 6ft fence so would like have the extra added strength of the concrete.. I know that idea is sort of frowned upon because of concerns about rotting out. But I got to thinking why can't I just one of the PVC sleeves that are normally meant to go on top of a post on a deck.. but instead put the sleeve around the part of the post that goes into the concrete. I think did some searching around and found 2 companies that basically sell PVC sleeves that are meant to go into the concrete and you just drop your post in them after they are set.. I think one of the them is call post shield

I can't figure what the difference is between the ones meant for above the deck vs. the PVC sleeve for above. I can get a 100in PVC sleeve at Lowes for $25 which would be pretty much the same price as the two post shield sleeves I would need per post.

The plan would be for 4in of gravel at the bottom them post sleeve drop in place then concrete around sleeve..

I have read everything from just dont use cedar, to use cedar but don't set in concrete, to use PT below ground and cedar above, or metal posts, or treat the cedar in copper green, to wrap in in copper at ground level, to wrap it with tyvek tape... but I haven't heard anyone recommend to use this sleeve idea..

anyway.. am i crazy or would this work..

sorry for the long post.. thanks for any thoughts/ideas

Comments (15)

  • john_hyatt
    12 years ago

    If I am understanding your idea it is to use pvc,like plumbing pipe,plant it in the hole,slide the cedar into it.

    You would then be covering up the cedar post completley.

    How am I doing so far ?
    J.

  • favabeans5
    Original Author
    12 years ago

    Hi,

    That's the idea.. the PVC would cover the cedar that is below grade and would only extend 2" above grade... the PVC would be open at the bottom to allow for drainage into the gravel..

    check out the post shield website to see how they present it.. I need to go 42" to get below frost line so a single post shield wouldn't cut it for me.. there is another one out there called post protector I think.. same idea thou.. PVC in ground.. slide ceder into PVC..

    Thanks...

  • favabeans5
    Original Author
    12 years ago

    These sleeves are square with a actual inside dimension of around 3.65" I believe and ribbed on the inside so the ribs allow for air flow/evaporation.. I don't want people to think I was just going to use a round PVC pipe.. the stuff I am talking about is like the composite deck post sleeves...

    the other benefit they say is that you can easily remove the post if it does rot.. you just pull it out of the sleeve and drop a new one in.. you can screw the sleeve to the post above grade.. to help hold it in place.. but really a good 42" of the post will be in this sleeve so I am not so much worried about strength or stability..

    this is not a commercial by the way.. i dont work for post shield.. i am actually talking about using a no name PVC sleeve I can buy at lowes that is really meant for covering above ground deck posts but using it in place of the post shield product since it seems like the same thing to me..

    thanks John.. I have read some of your posts on fencing.. clearly have a lot of knowledge in this area and sounds like you do really high quality work.. so definitely curious to hear what you think..

  • sierraeast
    12 years ago

    I'd be concerned about water/moisture being trapped between the sleeve and the post with no where to drain but down into the gravel. That's a good idea, but in wet conditions, you wont be allowing drainage out the sides.

  • john_hyatt
    12 years ago

    That is not the strangest idea I have come up on but its in the top ten.

    Just to get it straight in my own mind, dig the hole keeping dirt from falling back in 42'' deep, add gravel in the bottom, stick the sleeve in the hole,slide the post down the sleave landing on the gravel,fasten the post to the sleeve that extends 2' above grade leaving the rest of the post exposed.

    The advantage being the cedar post is not in contact with the dirt, all the water just drains down thru the gap in the sleeve down to the gravel until it reaches the point where the water just fills up the sleeve and over flows. The post can be removed,after all the framing is taken down,post replaced,framing reinstalled.

    Beans before I give you my take on this,what do you think I am going to say?

    J.

  • favabeans5
    Original Author
    12 years ago

    I think you will say its awesome.. :-)

    I have to go down 42" to get below the frost line here in northern illinois.. the concrete would be poured around the sleeve first.. so once that sets up you can drop the post into the sleeve.. really I could fill have the sleeve with gravel after that point.. as the post only goes down that far to deal with the frost line.. so I could drop another 10in of gravel into the sleeve and drop the post on top of that.. there would still be 32" of post in the ground..

    also whats the harm it in overflowing? seems to me that would take a lot of water.. it would have to soak down to 42inches of soil then fill all the back up assuming it doesn't just keep soaking down in the soil underneath the gravel.. wouldn't all that water just get soaked up by the concrete anyway or pour in through the gap between the post and the concrete at grade.. and the concrete would hold it against the post while the sleeve allows it to drain and or/dry....with the sleeve going all the way down at least the water would have somewhere easy to drain to and the ribs allow for air/drying..

    it's not my idea.. these two companies came up with it.. this is the link to the company that sells this product.. http://www.postshieldusa.com/cs/ or this other one.. http://www.postprotector.com/.. i'm just not planning to buy their sleeves but use the pvc sleeves just laying around lowes instead..

    i am looking for better alternatives besides dont use ceder and dont use concrete.. seems to me that if any alternative is going to end up with rot eventually why not just make it easier to repair..

    i also like the idea of the copper because I intend to use copper on the post caps.. and if it works and looks cool that would be great.. but if that just marginally improves the longevity of the post but you still end up having it rot out and need to remove the concrete then why not make that part easier..

    don't know.. these companies at least have me convinced but like they say a sucker is born every minute.. so maybe im that sucker.. I'm here hoping somebody can save me from a dumb idea but it at least seems logical to me.. the post prevents post to soil and post the cement contact which from what i hear are the two things that kill the post..

  • john_hyatt
    12 years ago

    I would think the main goal using the sleeve would be frost heave. That is the sleave would move up and down but the post would not.

    Becides that advantage your plan seems silly to me, and way not worth the extra work/money up against using 40 glav steel posts. Thats how I build upper end fence combined with fastening a 2x4 pt to the steel and framing off them. J.

  • favabeans5
    Original Author
    12 years ago

    so you dont think this sleeve thing will help keep the post from rotting? did you check out the company websites to hear their info or see their demos?

    assuming I am suing cedar and concrete what is the best way to keep it from rotting?

    Thanks... an easier alternative that helps preserve the wood is great to hear..

  • john_hyatt
    12 years ago

    Do not put cedar posts in the ground.

    J.

  • sierraeast
    12 years ago

    If you insist on cedar posts in the ground, you can coat the areas that are in ground and up a tad with asphalt emulsion. Dont coat the bottom of the post so that it can drain.but in the grand scheme of things, heed Hyatt's advise.

  • favabeans5
    Original Author
    12 years ago

    thanks to you both.. i got some local guys up here that I asked and they just said.. "we set posts in concrete" but didn't really answer any of my other questions.. guess he figured me out as someone that was just going to waste his time with questions but not actually buy anything..

    there is so much info out there it's impossible to tell who or what to believe.. search and have the places say cedar is awesome.. other half will say don't use it..

  • brickeyee
    12 years ago

    Use presusre treated wood graded for burial in the ground or plan on replacing the post every few years.

  • rlem1977
    12 years ago

    I agree with PaintItAll - Don't use the sleeves. If you can pull the posts out, you know water will seep in. Now you will have a 'container' for water unless you have good drainage. Either just set them in concrete, pour a footing and attach using anchors, use a coating material, or use PT.

  • ken_mcdonnell
    5 years ago

    This is all you need if you REALLY understand how decay occurs! Spoiler Alert! Moisture is NOT the cause of decay! Here's all the info you need!

    Be sure to go through their website & watch the videos.

  • HU-1539140830
    last year

    why not use cedar posts with roadbase on the bottom 4” and for backfill around the post? 3/4” or 1 1/2” roadbase will drain and keep moisture draining from post