|
| Author |
Message |
Lucidcryotank
Member
|
# Posted: 15 Jan 2023 03:25pm
Reply
Hi Folks!
My two greatest resources - rock and cedar. I'm building an open shed trying to use the materials I already have here, for what can't be considered a permanent structure. I need to stand up a couple of cedar log posts on top of natural rock (individual large stones like beach balls) without excavating or pouring concrete, or otherwise drilling a hole. I live on sloping glade rock, and don't want to create a tax assessable structure.
I have seen a method where you use a decent hammer drill to make a 1/2" hole in a large rock (after leveling and fill around), driving in a rebar peg, then drilling into the bottom of the log up into trunk, and sliding the log over the rebar peg in the rock.
It looks pretty simple, but I have questions on rock selection and hole depth.
1. Do you only use blocky or thick rocks? How big should they be? Does it matter if you drill all the way thru the rock if it's a larger but flat rock?
2. How deep should the holes be in both rock and timber? I'm thinking 6-8" in the rock, then maybe 12" in the log butt end, and 18" rebar pegs using 1/2“.
|
|
gcrank1
Member
|
# Posted: 15 Jan 2023 08:24pm - Edited by: gcrank1
Reply
In the part of Wisconsin I grew up in it was sand and gravel, most of the old farm structures were build on stacked stone from the fields. The base rocks were always selected to have a pretty flat bottom on the ground to more equally distribute the load and a flatish top that another smaller rock could be stacked on.
The ground, if not flat and level, would have one rock on the highest side and the rest stacked dry-fit to level for the bottom beams. They did not use 'round' rocks nor a rod, it was all set one upon the next.
Fwiw, They were relatively easy to jack up to shim back to level over time. That 'sand county farm' barn, the nice barn, was built in Aug 1897; many of the smaller buildings Im sure pre-dated that as the farmstead dated back into the 1850's. One by one the outbuildings were taken down, the last one in the early '70s?, as the roofs went bad and too much to fix and the need for them had passed. But the 'foundation ends' were still sound.
|
|
Lucidcryotank
Member
|
# Posted: 15 Jan 2023 08:52pm
Reply
For my shed, I've mounted an 11' log crossbeam between 2 trees and rested the small ends of two 20' cedar rafter logs on the beam. The big ends are resting on another log crossbeam at the far end, which sets on top of these two large industrial folding material totes. I want to brace and add support to my rafters by adding another 12 crossbeam near the small endsand supporting it with two vertical logs. So, a freestanding 8 ft log on top of a big rock (bushel basket size?), with a piece of 1/2" rebar pinning them together.
I've seen barns in southern Arkansas like what you describe. In I won't have walls or a bottom log on the sides.
|
|
gcrank1
Member
|
# Posted: 15 Jan 2023 10:42pm
Reply
Imho, if you use methods like the locals used for hundreds of years for the structures that lasted you wont go far wrong.
Deviate much from that and you are in uncharted territory.
|
|
Lucidcryotank
Member
|
# Posted: 16 Jan 2023 10:34am
Reply
HAH! After unbelievable searching, I found an example. This guy goes to greater lengths than I plan to, but his work is great and the idea is the same. See the pic. The entire video is good, if a little tedious. Skip to the part he starts selecting rocks. I think he's answered all my questions.
https://youtu.be/YBhgge17vw4
|
|
|
