berm sheds

From dave's thread:

What is the advantage of using the shoulder beam as opposed to staggering the cross beams?

Kyle Bob wrote:What is the advantage of using the shoulder beam as opposed to staggering the cross beams?

Maybe you have a bit of a drawing of what you have in mind?

Here's what I had in mind

Kyle,

I think your design is a big improvement over ours!   The only wonky bit would be the corner.   It would be good to see the layout for the corner.  

And since you seem to be mighty quick at sketchup, maybe you can whip out a berm shed 2.0:  if we could do it over again from scratch!

(this is the best reason to openly share designs - to optimize design)

Here are two concepts I came up with for the inside corner.  I have another I'm toying with.

I like the first one!

What about angle supports to keep the wall from shifting due to the berm weight?

Any thoughts on joinery?

Angle supports would be the same as the current design I think, i just didnt model them for expediency.  (I modeled this at work after hours using SolidWorks)

I wanted to avoid having half cross joints or balancing beams on center like the shoulders.

As shown, 1.7 does have the roof pieces half on the cross beam that goes down the middle of the corner.  This is a trade off.  The inside and outside corners already have 3 columns, adding a 4th on each side and another cross beam would make all those joints on the seam a full cross.

The joints on 1.8 are all full cross. But it costs half a chamber.  It uses a bunch of shoulder beams (not balanced on center) to hold up the roof pieces.

I started working on 1.9, which is similar to 1.8 but will have the full size corner chamber.  I can finish that one and refine the other two Monday if there is interest.

One comment on 1.7.  In the corner, the small roof logs have a longer span without support than the normal logs in the rest of the cells.  Those other logs have a support at the midway point.  Is there a reason that midway support beam/log can't be continued through to the miter joint in the corner?

You're right Mike, the two middle support beams from the adjacent cells could be cantilevered into the seam and butt up against the midway support beam.

A brand new video showing the truss joinery

I feel like while this is all fresh, it would be a good thing to thoroughly document all possible improvements.   And document the stuff that we like about the existing berm shed.  

I know that on multiple occasions there was a desire to do a shortcut and my response was "it is absolutely bizarre how you can have a 5% piece that is different and you tell people that that is the exception for some reason - but they somehow are drawn to the exception and are rock solid certain that THAT is the primary and best design."  So there were some points where there was a huge effort to avoid an exception.

In the first berm shed, I made a design error in NOT putting up the angle supports.  My error.  Mine.  All me.  There was heaps of work that needed to be done to fix that.  The current berm shed has oodles of angle supports:  two different designs.

Another thing I just cannot emphasize enough:  the first guy wanted to add drain grates.    When he skipped out, fred and jocelyn and I did earthworks to move all water away from the bermshed.  I think the earthworks approach is one tenth the cost and 20 times better.

Josiah has a series of videos coming out about details on the berm shed.

I made these models quickly to explain my original question and then talk about ideas for the corner.  They don't include anything that wasn't needed for those two purposes and I just guessed on the dimensions.
I can add corner braces and extend the support beams into the corner seam then post 1.7.1.  Then we can talk about what needs to be on 1.7.2 and repeat the process until eventually we have a 2.0 that someone can build.
I could use some actual dimensions of what's built as well as some good pictures of the existing corner.

Kyle, thanks for what you have done.  And thanks if you take it to 2.0!

Each cell is roughly 10x10.   I'll see what I can do about pics.

Newbie question.  The angle braces that hold the back wall look like they are buried at one end.  Is there a reason that they couldn't be angled a bit flatter and just connect to the front post just above grade?  Then you'd have one less log in the dirt and the angle would be stronger.  Walking from cell to cell wouldn't be as easy though...

Mike Haasl wrote:Newbie question.  The angle braces that hold the back wall look like they are buried at one end.  Is there a reason that they couldn't be angled a bit flatter and just connect to the front post just above grade?  Then you'd have one less log in the dirt and the angle would be stronger.  Walking from cell to cell wouldn't be as easy though...

Would need a much longer log, which would then have to be larger diameter to boot... but then if one is short on logs this design may not be a good fit anyhow!

Reducing the angle at which the brace intersects the rear wall is advantageous... but, it seems to me that the other end of the brace is more likely to be the weaker link, beinf a log-dirt interface rather than log-log. Certainly likely to see decay issues first. And, that angle is better off steep. So overall, the angles are a compromise..


On the other hand, joining the brace to the base of a post would tie the structure together above dirt level, and the weight of the roof/soil would provide some sort of anchoring force even when the below-ground parts rot away...

Here is your image slighly modified to be a little more accurate.

Yes, it is all about getting better access between cells.

going a little further, here are some important bits.

Note the slope of the ground to the left.  That is the important drainage thing.

Note the bigger eave to help keep the posts dry.

Note the membrane.

Note the berm part in the back that is steeper than the angle of repose.

Note that the earth on top is really shallow over the eave and thicker near the back.

And then there is the whole thing with the facade.

Why will the dirt on the back of the berm stay put, if it is steeper than the angle of repose?

D Nikolls wrote:Why will the dirt on the back of the berm stay put, if it is steeper than the angle of repose?

On the backside, make sure to work lots of branch-like stuff into the dirt on the back.

Great video Paul!  Same basic process they used for the great wall of China....layers of sticks and the bricks are used as a façade which much of the thousands of miles of wall lack.  Yet a few thousand years later it's still up, standing and resisting at steep angles.


Makes one want to start building structured hugels!!!  Plants make a gorgeous (and tasty) façade :)

Here's a bunch of sticks inside the berm so that we can have a steeper angle of repose.

Of course, if you have LOTS of space on the berm side, then don't worry about the sticks and just go with the angle of repose for the dirt you are putting there.

paul wheaton wrote:On the backside, make sure to work lots of branch-like stuff into the dirt on the back.

Wow WOW!  That's the kind of video I never would have watched except that it was posted here.  And it is such a very cool concept!  I can't wait to put this into practice -- it immediately and inexpensively solves a problem I have!  THANK YOU!

One other benefit for an application against a wall, such as a berm shed or a wofati, would be that it would greatly reduce the force of this mass pushing against the wall.  Done right, you should be able to eliminate the need for bracing timbers that get in the way inside the berm shed.

Greg Martin wrote:One other benefit for an application against a wall, such as a berm shed or a wofati, would be that it would greatly reduce the force of this mass pushing against the wall.  Done right, you should be able to eliminate the need for bracing timbers that get in the way inside the berm shed.

Wow!  I had not thought of that!  True!

paul wheaton wrote:

Greg Martin wrote:One other benefit for an application against a wall, such as a berm shed or a wofati, would be that it would greatly reduce the force of this mass pushing against the wall.  Done right, you should be able to eliminate the need for bracing timbers that get in the way inside the berm shed.

Wow!  I had not thought of that!  True!

I assumed that load reduction was the point!

Nifty stuff. Presumably in a bermshed/wofati sort of application there will also be roots helping hold it together, after a while..

paul wheaton wrote:

Greg Martin wrote:One other benefit for an application against a wall, such as a berm shed or a wofati, would be that it would greatly reduce the force of this mass pushing against the wall.  Done right, you should be able to eliminate the need for bracing timbers that get in the way inside the berm shed.

Wow!  I had not thought of that!  True!

Maybe, I think so...  Depends what it's compared to, I think.  If you're comparing a steep pile with sticks to a flatter one at the angle of repose, yes there would be far less load on the wall.  If you're comparing a steep slope held together with magic to one held together with internal sticks, I'm guessing it would be better but maybe not tremendously better.

Has the berm shed exhibited evidence of pressure from the stick laden steep dirt?  If so, I'd trust that evidence of pressure and brace accordingly.

The berm shed showed sadness from the dirt on the back that did not have sticks in it - and there were not the angle braces.

paul wheaton wrote:

Greg Martin wrote:One other benefit for an application against a wall, such as a berm shed or a wofati, would be that it would greatly reduce the force of this mass pushing against the wall.  Done right, you should be able to eliminate the need for bracing timbers that get in the way inside the berm shed.

Wow!  I had not thought of that!  True!

What about Earth Bags? (another form of MSE) could allow a curtain wall behind the timber wall to take the whole load, reduce/eliminate soil infiltration, possibly create a space for insulation that's not subject to compaction...
Could the benefits outweigh the added plastic materials?

I prefer to try it first with all natural materials.  

paul wheaton wrote:

Greg Martin wrote:One other benefit for an application against a wall, such as a berm shed or a wofati, would be that it would greatly reduce the force of this mass pushing against the wall.  Done right, you should be able to eliminate the need for bracing timbers that get in the way inside the berm shed.

Wow!  I had not thought of that!  True!

There are some interesting repercussions regarding what can be done with this Paul!

Here's the third roof geometry I could think of for the corner.  I'll work on 1.7.1 with the suggestions from this weekend when I get some time, probably this afternoon.

Why make the corner lower?

paul wheaton wrote:Why make the corner lower?

It makes the corner section one pitch with longer logs instead of having to deal with the two pitches meeting on the diagonal seam.

But, concept 1.8 also does this, by cutting the whole corner at an angle. I like this one, unless there is some permanent item meant to go in the corner. Corner space is harder to access/use, so might as well save a bit of time and materials IMO.

Concept 1.8 also lends itself extra nicely to non-square corners. No reason the berm needs to have square corners or form any sort of rectilinear shape..

D Nikolls wrote:

paul wheaton wrote:Why make the corner lower?

It makes the corner section one pitch with longer logs instead of having to deal with the two pitches meeting on the diagonal seam.

What he said.  

I still think 1.7 is the best layout, I posted this because it is a viable geometry and worth discussing.

I very much like seeing design improvements!  I like how there are fewer posts in the corner.

One issue is that the billboard material is often not entirely water proof.  So with the horizontal logs, this could encourage leaks.  

I can see that now.  Roofing logs perpendicular to the flow of water off the roof could create little pools between the logs.  That's not good.

I like the general direction of the simpler build.  I wonder if there could be a way to eliminate the triple post in the back corner and the triple post in the near corner.

We have an experiment with the end that is looking really good so far.  Let's see if I can describe it with english .....


For the back wall (blue), a diagonal (green) goes at a pretty steep angle to the ground.   For the near posts (red), a diagonal (purple) goes at a pretty gentle angle to the ground.  As the roof logs are placed on this, the water flows away from the front edge.   And the wood underneath remains to be protected.

here is a pic from jennifer showing construction of the berm shed end.  josiah is planning on putting out a video.