My new house has a back porch. The roof is held up by a couple of 4 x
4 treated posts. Both posts were green when installed. Now, after 6
months, both posts are warping. There is as much as a 1" deflection
from the top(or bottom) to the middle. Is there anything I can do
about it? These posts have not been stained or sealed.
Probably means they were treated way before they were cured, then finally
dried out and warped after installation. Bad lumber. Short of replacing
them, the bend is pretty hard to cure, but other than being cosmetically
unappealing, probably not yet a worry, structurally.
Deflection does indeed imply stress. I don't read this as exceeding
the posts capacity, but more of cheap, wet treated lumber trying to
"straighten" itself out by bowing. I'd be surprised if there wasn't
some twist in there as well.
To the OP - how tall is the post?
Is there any twist in the post?
A 9' tall 4"x4" post is not a great idea. Too slender. Some people
clad them in 1x for appearances and to help keep them straight. Other
people would use a larger post, or a treated LVL.
It my opinion, backed up by the current situation, it was the wrong
thing to use. Doesn't make sense to me to expend valuable effort to
make an attempt to fix faulty materials. Particularly attempts with
little chance of success.
I think you answered your question to me........
""Why would you assume that the designer undersized the posts? "
I didn't necessarily assume the designer undersized the posts......
designers & engineers make mistakes and contractors do sometimes cut
corners. Rather than just telling him how to straighten or replace
the posts I thought it prudent to dg a little deeper as to why they're
I haven't seen that many bowed posts in my experience, so w/o seeing
this installation (or pictures) it seemed reasonable to ask if they
were maybe overloaded.
It could have been a boot legged install
(I know he said "my new house, maybe new to him but not new)
Also I've seen new houses (custom design & engineered) with grossly
undermized members & major deflection issues, so it does happen.
wrt to my use of COULD, I really meant "he possibly could".
I know I could (definitely) straighten them, if for no other reason but
to prove it could be done.
but in his situation I'd make sure the member was correctly sized &
then replace the bowed posts with straight one........
quickest & cheapest way
Hmmm, seems we have a horse race! Too bad we can't have two identical
post installations and see who's "right". I have my hunches. ;)
Not having seen the situation, I can't say for sure, but you may very
well be right. As long as the post is a simple installation with a
post cap and base, it would be pretty trivial. If the installation is
more complex with a deck wrapping around the post and/or beams let into
the sides, it would obviously be much more complex to swap out.
Now that we're getting more info about the install.............looks
like straightening might be easier?
You didn't answer my questions about the bow; simple single axis? bowed
in two directions? are we SURE they're not overloaded?
If they're only bowed an inch in one direction, it can be straightened;
I'd use a minimum 4x4 steel square tube as a strong back
but how do we get them to stay straight?????
(btw two 2x6's screwed to the straighened psot would take out about 70%
of the bow)
maybe get them saturated wet before straightening? a little wood
straighten & then let them dry out
are we sure this is easier than replacement?
how about just living with it?
maybe he's shopping an answer?
a lot of folks do that
or by witholding information they think they're "helping" by
"simplifing" the problem;
problem is, if they need to ask thye probably don't know which facts
are importatnt & which aren't
inadequate problem description / definition usually leads to a
sub-optimal (or wrong) answer :)
I must apologize. I am not shopping an answer. I want advice. I am
in a brand new house. I had it built by the most respected contractor
in our area. There is no twist. Only a deflection in one direction
and both in the same direction. One post deflects 1/2" in the center.
The other deflects 3/8". My principal concern is that the
deflection is from overload. I think these posts only bear about 1/4
of the weight of a stick framed porch roof with fiberglass shingles.
It is in a corner of a wing protruding from the house. Any advice
would be appreciated. I appreciate your willingness to respond.
Fookin' right you should apologize for wasting people's time.
Your original post said a 1" deflection, now it's half that or less?
The deflection is not from overload. It's a brand new house, ask the
According to the lumber yard where we got the posts, they would have
been dried before being treated. However, they were not dried after
being treated. Do you think I could force them back straight if I put
an I beam on the bowed in side and used a clamp to pull in the center?
Dubious. It might work, but I don't think it would stick. Once you
pulled it back into place and removed the brace it would drift back.
You're fighting the natural inclination (grain) of the wood. Once the
lumber is cut out of the log, all of those nice round sections (with
opposing forces that pretty much cancel each other out) disappear.
You're left with a piece of wood that wants to relieve stress. This is
a major problem with treated wood since, as you've discovered, most of
the stuff is sent out from the lumberyard soaking wet. One of the
reasons that some people use posts that are built up from a couple (or
more) pieces of lumber.
On Thu, 08 Dec 2005 20:21:20 GMT, snipped-for-privacy@NOSPAMjuno.com wrote:
Treated lumber is notorious for bending and twisting. Pressure
treating forces water into the wood. Even is the wood is dry, it's
once again wettened during the processing. When it drys, it warps.
I had a 10' 4x4. It was straight when I bought it. A couple weeks
later I go to use it on a shed and find its so twisted that the bottom
of the post faces north and the top faces east. I was not in a
position to go buy another one and wanted to finish my project. I put
the bottom in the ground and started nailing the lower boards to it,
using ringed spikes. Each board when driven securely straightened the
post a little. By the time I go to the top, it was only off by 1/2
inch. Close enough for what I was building. A couple weeks later I
added a few more spikes and got it even straighter. It's stayed that
way since. Of course I have a wall mounted to it, not just posts in
the middle of something.
The easiest way tot "fix" the posts is to replace them.
Go to a real lumber yard (if you've got one available) & try to buy
some treated 4x4's that are already dry. If dry / treated posts not
available, go for the driest you can find (if you or they have a
moisture meter available, even better)
Ideally you want to buy posts under 19% moisture content, closer to 10%
would be better. I have purrchased treated sills (Hem-Fir) that
actually dripped liquid when crushed in a vise.
Also when selecting the posts, look at the ends. AVOID posts cut from
the very center of the tree. Try to get posts with the end grain with
a little curvature as possible. Less curve means cut further from tree
center. This grain pattern will tend to dry with less cracking,
twisting & warping.
Another possibilty (but a lot of work) is to "fixture" new wet posts to
restrain them while they dry.
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.