Our barn build

[rbstern]

Started construction this weekend. 36x36 monitor style, derived from this plan from the Univ. of Tennesse extension: http://web.utk.edu/~ggrandle/Programs/Plans/T4161.pdf

My neighbor is a semi-retired grader/earth mover. He dug the foundation for our house, and has done some other land clearing for us. Had him clear some space at the edge of our woods and form a pad. Last weekend I laid out the dimensions of the building with masonry line. We've had some heavy rain in the meantime, and the water went exactly where intended. An experienced, semi-retired grader makes an excellent neighbor!



This weekend, beautiful weather with the exception of some heavy wind. The wife and I were able to get the first row of posts (back of barn) stood up. We had some family obligations and were also doing garden prep work, and the first post was definitely a "let's go slow and figure out our methods" process. Feel pretty comfortable we can do about 4 posts in a day, including digging, placement, bracing, removing the spoils, mixing and pouring concrete, and resting our tired, creaky bodies. Expect a couple of more weekends to stand all sixteen posts, which is fine, since we are not in a particular hurry.



Nearly rented an auger to do the post holes, but after a lot of reading, pondering, and digging a test hole, decided to dig them with the backhoe on my LS. It's a much bigger hole than an auger makes, but I chose to use a variation of a "collar" style method that the experts over at the Hansen pole building blog describe. Their preferred method is using some sort of fixture (imagine a heavy wire basket) to stand the post 6" off the ground so wet concrete flows under it, and then 18" of depth/contact with the post itself. Didn't have a good way to do the stand off, so instead poured an 80lb. bag dry, in the hole as the base, well tamped, set the post on that, and then another four to five bags of mixed concrete to get 18" of contact with the post. Used a concrete vibrator to max consistency and adhesion to the post. I've decided not to backfill with the red clay. Waiting on our local gravel and rock guy to bring a load of crusher run for the backfill. It's a couple more bags of concrete than I planned per hole, but like the result I am getting and think it will have good resistance to both settling and uplift.



Couple of tool notes: The concrete vibrator is the $120 Harbor Freight version. It's pure chinesium, but it works great. Ran it with a Sportsman 1000w generator. The tool works well, feels solidly built, and has a long power cord so I could keep the genny well away from the hole without an extension cord. Also, on the topic of Harbor Freight, I bought the smaller (60lb) Central Machinery concrete mixer a couple of years ago. My wife likes to do masonry projects on the property. We probably mixed a half dozen bags of mason cement before the motor quit. Very poor quality motor. I replaced that motor with a more powerful American made motor, and now that thing runs great and easily mixes an 80lb sack. Mixed 20 bags this weekend, never missed a beat. Last but not least: Bought a Swanson post level for this project. Will never set another post without one.

Some supplier and material notes: We use a local building supplies store called Yoders (Fair Play, SC). Great vendor; super friendly and customer service oriented, and very good pricing. They charge a whopping $11 for delivery, any size order, and they are 20 miles from us. They special ordered the 20' and 18' posts (UC4B...ground contact/burial, structural applications), and had them to us in less than a week. The pallet of concrete turned out to be Sakrete. I'm used to buying Quickrete at Home Depot. I now like the Sakrete MUCH better. It was far more consistent than what I've gotten from Home Depot.

So, that's it. Started. Will post updates to the thread as this progresses.

 

[K5lwq]

Looks like a good start. Look forward to seeing it come together.

 

[cat fever]

Looking forward to your progress.

 

[EddieWalker]

I'm looking forward to following your progress.

Why didn't you fill the hole with concrete? 99% of the time when a post rots, it's right at the surface because that's where moisture sits. Having the concrete come out of the hole a little bit, and sloping away makes it impossible for water to remain around the base of the post.

 

[rbstern]

I'm looking forward to following your progress.

Why didn't you fill the hole with concrete? 99% of the time when a post rots, it's right at the surface because that's where moisture sits. Having the concrete come out of the hole a little bit, and sloping away makes it impossible for water to remain around the base of the post.

Eddie, that would be a lot of concrete. Way too much to mix a bag at a time. Could certainly be done with a mixer truck, but since we're on a go slow plan and not digging and setting all posts at the same time, we'd have to have multiple, short load deliveries, and that would be silly expensive. My understanding is that no practical benefit is gained from that much concrete.

The pad is constructed to keep water away, and we'll landscape around the barn to keep the drainage working well. The crusher run backfill will compact and drain well. Even if the backfill was something that didn't drain well (our native red clay), my reading indicates that UC4B treated posts can withstand even poor drainage conditions for decades. When we rebuilt our front entrance last year, I pulled the existing two 6x6 gate posts. They were set with very minimal concrete, with red clay backfill, in 1994. They were the 1994 equivalent of the current UC4B "burial/ground contact/structural duty" standard. The posts were in such good shape, I was able to pressure wash them and reuse them as decorative posts at the ends of the new gate/fence.

I think there's a lot of misconception out there about the levels of chemical treatment in posts. The posts that are treated to the higher, structural duty standard can take a lot of abuse, for a long time. The problems that do happen are more often than not with the UC4A treatment posts, sold as "burial and ground contact," at the big box stores. They aren't as durable.

 

[EddieWalker]

There will be moisture getting into the ground at every exterior post. The hole that you dug for the posts will act like a swimming pool and hold water. Water will always go where there is no resistance. The area around your post that does not have concrete will be a vacuum for the moisture in the soil around it. Filling with compacted soil, or gravel, will provide a place for moisture to remain over an extended period of time.

I understand that it's a lot of work to fill in the hole you dug for your posts, but when you dig an oversized hole, you have to consider what additional steps need to be taken to deal with such a huge hole. If it was me, I would have dumped the concrete into the hole dry, then for the top six inches or so, mixed it and created a slope to keep water away from the post.

You could be fine doing it this way, but if a post ever fails, it will be because you created a wet area at the base of the posts that could of been avoided. Expecting every post to last as long as the others isn't realistic. There is always that odd ball that rots faster then the others.

 

[rbstern]

There will be moisture getting into the ground at every exterior post. The hole that you dug for the posts will act like a swimming pool and hold water. Water will always go where there is no resistance. The area around your post that does not have concrete will be a vacuum for the moisture in the soil around it. Filling with compacted soil, or gravel, will provide a place for moisture to remain over an extended period of time.

I understand that it's a lot of work to fill in the hole you dug for your posts, but when you dig an oversized hole, you have to consider what additional steps need to be taken to deal with such a huge hole. If it was me, I would have dumped the concrete into the hole dry, then for the top six inches or so, mixed it and created a slope to keep water away from the post.

You could be fine doing it this way, but if a post ever fails, it will be because you created a wet area at the base of the posts that could of been avoided. Expecting every post to last as long as the others isn't realistic. There is always that odd ball that rots faster then the others.

I understand where you are coming from. Was in the same place until I did a lot more reading. With the UC4B standard, the posts are designed to be used in immersed fresh water applications (think dock piers). Also, our clay does drain. Slower than sand, for sure, but it does drain.

Let's revisit this thread in 25 to 30 years, and we'll see what happened.

 

[rbstern]

Another sunny Saturday, another four posts set. It's heavy work, but quite enjoyable when doing it without the pressure of a schedule. Getting better at digging tighter holes with the backhoe, so less cement and less fill needed per hole. No substitute for time on the sticks. Also hit sizable rocks in three of the holes. Fortunately, they were sandstone; soft enough to break up with a pick axe and 8lb. sledge, when the backhoe teeth couldn't get enough of a bite to break them. Between that, shoveling cement, gravel, and clay, my arms haven't had this much of a workout since I last belonged to a gym (1980s).

Hope to set another couple of posts tomorrow.

 

[rbstern]

Got the remaining eight posts in the ground this weekend. Tired and sore, but in a good way. Beautiful weather. 39 degrees when I got started, and mid-seventies by late morning.

 

[Xfaxman]