Installing unirac ground mount piles

[df0rster]

The instructions don't really specify how to install the C piles/posts that come with this system. From what I can tell they are designed to be driven into the ground about 6 feet. I don't have the ability to do that. I can use an auger to get about 4-5' deep and use concrete to set the posts. I think that should be just as good or better than driving them into the ground. But again there isn't much DIY information out there on these ground mount systems. So I am wondering about options or how others have done it.

Any tips?

Thanks!

[SunEagle]

The instructions don't really specify how to install the C piles/posts that come with this system. From what I can tell they are designed to be driven into the ground about 6 feet. I don't have the ability to do that. I can use an auger to get about 4-5' deep and use concrete to set the posts. I think that should be just as good or better than driving them into the ground. But again there isn't much DIY information out there on these ground mount systems. So I am wondering about options or how others have done it.

Any tips?

Thanks!

I guess it will come down to the wind calculations on your permit to determine if the poles with concrete footers will be enough.

[Ampster]

I did a roof mount years ago with Unirac and the building department approved Unirac's engineering drawings without a wet signature. I am in a rural area and the building department is the County, There are a lot more ground mounts from anecdotal observations so I am assuming that there is some institutional knowledge.

If I was going to do that I was going to look at Unirac and IronRidge and see what the differences were and pick the one that fits my prospective situation. I have not explored the depth problem but my layman engineering was going to see if some elements of a ballast mount could compensate. The idea was to extend the concrete above the ground using Sonotube forms to get the same or more concrete with a shallower hole than required for a full depth hole. I am making assumptions that may not be valid. I have seen some installations designed that way but I do not know the engineering details.

[df0rster]

I did a roof mount years ago with Unirac and the building department approved Unirac's engineering drawings without a wet signature. I am in a rural area and the building department is the County, There are a lot more ground mounts from anecdotal observations so I am assuming that there is some institutional knowledge.

If I was going to do that I was going to look at Unirac and IronRidge and see what the differences were and pick the one that fits my prospective situation. I have not explored the depth problem but my layman engineering was going to see if some elements of a ballast mount could compensate. The idea was to extend the concrete above the ground using Sonotube forms to get the same or more concrete with a shallower hole than required for a full depth hole. I am making assumptions that may not be valid. I have seen some installations designed that way but I do not know the engineering details.

I assumed there would be some general instructions about installing the piles with the documentation. I guess they are not really intended as DIY instructions..

There is no building department for my area, I couldn't get permits if I wanted to. Maybe I will contact Unirac and see if they have recommendations.

thanks!

[df0rster]

I found some construction drawings on the Unirac site. They weren't that easy to find but they are there.

The specs show that a 24" diameter 6' deep concrete pier can be used for the posts. This seems huge to me, but I guess they are designing for 100 mph winds and I'm sure using a huge safety factor. It seems to me that the panels would break off or the diagonal bracing would shear bolts or break long before 6' of concrete piers would pull up out of the ground or bend over.

But I think I can borrow or rent an auger for my skid steer and manage a 6' hole easier than I can find someone to drive the poles straight into the ground 6'. Seems like it would take an experience installer to get that pile accurately placed and straight. The concrete option will be more work for me, but easier and more accurate I think.