Definitely not a fine woodworking question but I thought the intelligence of
the Wreck might have some suggestions.
I'm about to embark on building an adobe wall outside my house (clay bricks
basically). I intend to put in a gate and in order to hang this thing, I
will be putting prolly 3"x8" rough cut cedar or pine into the ground against
the wall ends to create the frame. I plan to set these in concrete around
24" deep. I'll then fasten the wood to the wall but can't rely on the
adobe to provide a whole lot of support (hence, sinking the frame into the
ground). I've got termites in this area and I'm worried about the wood
rotting out as well.
I will be using an asphaltum in the morter and was wondering if just dipping
the ends of the boards into this stuff would provide me the protection I
need. Not too worried about the termites as the wood will be encased in
concrete. Would this work or is there a better way?
Once upon a time the above was basic practice; however, things change.
Think you will find that pouring concrete around a wooden post that is
maybe 24" down in the ground won't solve your problem.
Suggest you consider the following;
Pour a concrete cylinder that is below the frost line and rises above
grade level at least 8" that contains about 4, 1/2"-13 standard anchor
bolts (The bottom of the bolt has a right angle bend, the other is
A commercial form for this is known as a "Sona tube".
It is basically a paper tube that is coated so it doesn't stick to the
Any decent electrical contractor who installs parking lot lighting can
give you a source.
Form a steel plate in the shape of a "U" that gets bolted to the anchor
bolts below and has a flap on each side of the post that allows thru
You may be able to find a commercial item but if you don't, NBD.
Any machine shop with a press brake and a welder can easily make them.
What I have described is almost standard construction here in SoCal.
Lew is right about ow it's done now and if I were building a deck it's the
only way I'd go. For your application I wouldn't hesitate to go with the
concrete-in-a-hole method. It was used 20 yrs ago on my deck and it's still
standing tall with no signs of rot. With your application it should be no
problem at all although, like Les said, go below frost - and 30" would be my
minimum. With regard to the termites, treated lumber is termite resistant
and the ugly greenish color will weather away. If you don't want to wait
that long, it appears that Penofin (type it into a search engine) has a
product that only requires you to wait 30 days for a cureing time before
application. The stuff sounds imressive but you'll have to get it online
unless you live near one on of the very few dealers - comes from Australia.
Heck, there's bound to be another product that does the same thing and id
avalable at one of the box stores. Good luck!
surrounding wood in concrete does not protect from termites.
either a crack might let them in, or they get in from above the concrete.
water or landscaping might push some dirt over the concrete and let termites
get to the wood!
and once dirt washes up to the wood if termites dont get to it, I've seen
many post rot out of the concrete. keep the dirt clear.dont cover it on
where I work here in Texas when a post or any wood is set in the ground and
attached to the house or touching our company will cancel the home owners
warrenty for their termite contract.
keep the area clear and the ground and post treated both for termite and
Yeah, the termites are pretty prolific here too (NM). I've actually decided
to mount the post to the wall above the ground. After all the trouble of
mounting, layout, etc...I just decided to heck with it and will put some
gringo blocks in the adobe and mount to them. The gate will be pretty
small so it shouldn't need much support.
On a side note, I've noticed the termites don't mess with the treated
lumber. I have a few cutoffs of regular doug fir and some treated stuff
out in the yard. Went to clean them up the other day and the termites were
all over the doug fir but didn't tough the treated stuff.
I've been reading about a new chem (actually not that new) called Termidor
that supposedly works very well against the critters. Might have to
inquire about that one of these days.
Termidor and Premise are the two top professional termiticides on the
market today. Both work on what's called a "non-repellent" basis. I
happen to prefer Premise (by Bayer) and think it's safer to use with
kids and pets around. Termites live in a colony 20-25 feet underground
and commute to your house 24/7 to forage (get food/bring it back). A
typical colony could be 300,000 to 3,000,000. Think of a 55-gallon drum
full of squirming rice and you'd have a small colony. As they pass thru
the treated soil, they get some residue of these products on their
bodies, and termites socially preen themselves and inadvertently the
checmical gets into their systems. The excess food (cellulose) they
bring back from your house is reguritated in a food store to feed
larvae, pupae, queen & king... plus any underdeveloped termite. So
tainted food is shared with the colony. These chemicals act like
time-release drugs, and it can take 15 to 45 days to eliminate the
colony... but they usually all die.
I inspect houses, and in addition to wood, termites eat the paper on
sheetrock, yellow pages, books, cardboard, newspaper, some ceiling
tiles, homosote board, masonite, and just about anything with a
cellulose base. PT wood is untasty when new, but if you lie it on the
ground the chemical will eventually leach out and the termites will
infest the wood. And to throw a rock in the gears... Carpenter Ants do
not eat wood... but they can cause almost identical sorts of damage as
they hollow out wood to build sub-colony nests in houses.
Both are officially called WDI's (Wood Destroying Insects) in our
nationally spec'd reports. Two other WDIs are Carpenter Bees and Powder
Post Beetles. If you sink the wood into the concrete, you're not
helping the wood, and that's why the PT warranty is voided if the wood
is placed on/in the ground and not on a raised sonotube or cement
Termidor and Premise are not available to the general public AFAIK. You
have to have a specific termite license to buy/use it here in New England.
Termite 101 is over...
James "Cubby" Culbertson wrote:
Wow, thanks for the lesson!
You're right that they eat anything with cellulose. I first noticed their
presence when I noticed an expansion joint had been all but destroyed by
I hadn't heard of Premise before. I may look into that as I do have the
pets and us to worry about! I've had the outside treated before. The guy
hits em with some form of Borax but not sure of the trade name. He says it
repells them and keeps the house safe. Hmmm, not too sure of that one.
I've had carpenter ants before. Thankfully they don't eat the wood, they
spit it out and it's pretty easy to discover them early on with all the
little piles of sawdust around!
I would think that someone that sold "Pre-treated Lumber" specifically for
termites would make a fortune.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.