Cedar sign repair - need advice

[ron_churches]

Hi everyone,

I'm in the process of refurbishing a sign that fell over in a recent storm. The posts appear to have broken at ground level because they were completely rotted. The sign is 1 1/2" thick cedar and is at around 30ish square feet in surface area. Originally it was installed on two 4x4 cedar posts that were boxed in with 1x6 and 1x4 to add detail and appears to be buried 42" below grade (both 4x4 and 1x box). I am wondering if it would be ok to dig new holes (to avoid having to pull the old cement) and plant pressure treated 4x4's without the 1x boxing the required 42" and remount the sign using 4 lag bolts ( it held with 3 for many years.

Thanks,
Ron

[joe]

Ron,

Glad to see you have this kind of work. Like you, I have several of these to do each year. At this time I have three in my shop. I love this kind of work.

Cedar post will last a long time but don't use concrete. It holds moisture and will crack promotes rotting. I use a combination of sand and gravel. That will hold the posts tighter and allows moisture to perculate through.Over time the sand and gravel will get tighter and hold the post better. After the sign is installed I pour a couple of cups of Spectricide, bug killer, in each hole.

Watch out for treated posts, they can warp. Your worst demon for any kind of posts is the weed-eater.

I'll be visiting two sign locations next week that will be brought in for re-ferbs. Will posting a couple of photo's

Joe

[Dish]

Would this work with cedar posts? Claims it is water resistance, looks like a good product.

[ron_churches]

Would this work with cedar posts? Claims it is water resistance, looks like a good product.

I think my question was too confusing. Im really asking if two 4x4 posts are sufficient for this large of a sign. I am concerned about wind forces.

[ron_churches]

I think my question was too confusing. Im really asking if two 4x4 posts are sufficient for this large of a sign. I am concerned about wind forces.

[bobmoore]

you can do all kinds of calculations of wind load but I would check first with any state or local codes for where and how to mount signs. I have always used cedar 6 x 6 for anything over 24 ft as much for cosmetic appeal as for strength.

[Dish]

You do not put your location. So to answer your question, I think you should contact a civil engineer in your area and get them to spec. out the mounting system (size of supports, footer size and depth). If you are asking the question then you need to get the correct answer, just not some one giving advice a forum that may not be any better at these types of calculations than you are. Guesstimating can get one in serious trouble should someone get injured if the sign mounting system fails. JM.02

[Pennywood]

Hi Ron,

I'd guess a sign that size weighs about 120#, so 4x4's will easily support that weight. The wind load is harder to calculate, because that depends on how high the sign is mounted, and how far away from the sign each post is mounted, and if the sign hangs away from the top cross-member. Without knowing how much wind it will be exposed to, It difficult to say whether unrotted wood could reasonably be expected to withstand the forces the sign will be exposed to. Think of the height of the exposed post as a lever constantly pushing and pulling against its mount.

Joe's suggestion that you use a mix of sand and gravel is also an excellent suggestion, and depending on the type of soil and climate, can last a long time. Here in Montana the frost line is 42", so that tends to make posts without concrete loose in the spring.

I've had good luck in the past extracting the rotted wood from the existing concrete. If I'm understanding correctly a 4x4 wrapped with 1x material would leave you with 5" voids that you could fill with a new 4x4 and 1x wrap. Alternately a 6x6 could be cut down to fit into the void. Bob is right about the visual appeal of 6x6's, it really improves the general appearance of the sign to have a visually balanced mount. We sometimes sleeve a post with steel because it's resistant to the evil weed eater, and won't rot. Non-shrink grout will stabilize the sleeve, and gives you a little room to plumb the post if the previous installer was delinquent in the details.

One of the biggest reasons wood posts rot at grade is poor drainage. So Take that into consideration if you decide to dig new holes.

[joe]

Why skimp on posts? Healthy, beautiful post are the easiest way to make a sign look valuable. Weeney little sticks coming out of the ground holding a nice sign degrades the whole project.

Concrete will rot off just about any wood. Use gravel and sand, intermixed, as a mortar. Here in my state we have lots of wind. Concrete will ultimately crack and hold water. The sand, gravel mix will get tighter and tighter around posts over time. Then if you ever need to move the sign they can be jacked out of the ground. I've been doing this for twenty years with no failures.

The easiest and fastest way to give posts a little class if to use a large roundover to ease up the edges. Once done, they no longer look like a posts. My largest bit is a three inch. The photo shows the effect.