starplate connectors and cheap housing

[akemt]

So, we're still dreaming of a log home and getting closer in the sense that we are now totally debt free, but we still need to buy land, etc.

Anyway, our problem is that we'd LOVE to do log but, like many on this forum, need someplace to live while building that DOESN'T cost more than our logs. Motorhomes/trailers aren't as readily available here as in the lower 48, so that is rare and a usually cold/wet/nasty option when found (and we have 4 kids at home). So, I've looked into yurts and tipis, small cabin construction, various other possibilities, and my current research interest is dealing with starplate connectors.

Here's a Mother Earth News article that explains it: http://www.motherearthnews.com/Do-It-Yourself/1985-01-01/The-Starplate-Connection.aspx And I've seen adds for starplate connectors in Countryside magazine at strombergschickens.com

So here's the dilemma/question: We need more space than a 9' (what they state as limits -- 2 x 4x 9' struts = 10,000 lb total roof load per website, about 57lbs/sq ft) strut would allow. We plan to switch to 2 x 6's regardless for insulation reasons, fyi. We could build 3 huts for the needed space, but would prefer one large one with a self-supported loft and one small one to house the bathroom/closet/storage/entry. We're considering doing something like use 16' 2 x 6's/8's with a center post for roof support, and possibly even a second hut frame immediately inside the first for a doubled-wall (extra insulation and also extra strength/support when tied together sufficiently). Building codes here aren't an issue (they only care about septic and zoning). I'm wondering if any of you have experience with these buildings and if you think the above would be a safe/strong building option for our cheap place to live while building. I've emailed the manufacturers about extending the length, adding a center post, and doubling the wall, and received no response to date. My non-engineer brain tells me that should be enough overkill to make it safe and strong (along with all the extra studs we'd have to tie it together with for wall sheathing, etc), but I just want to be on the safe side.

Thanks guys and gals,

[WillandHelen]

This is a bit off subject. But consider building a garage or shop building with a bathroom and everything to live in for a couple of years. Then you will have a permenant good structure that will serve you for decades. The extra living space can help you build a smaller house in the long run anyway. That is what I did. If you plan it all out right, then I think it can be much better and more cost effective than temporary structures.

[NM bound]

This is a bit off subject. But consider building a garage or shop building with a bathroom and everything to live in for a couple of years. Then you will have a permenant good structure that will serve you for decades. The extra living space can help you build a smaller house in the long run anyway. That is what I did. If you plan it all out right, then I think it can be much better and more cost effective than temporary structures.


That is our plan as well, though our garage is not log-it was already up before we found LHBA & were 'educated'.
We knew living in an RV for however long it takes to build was NOT the best solution. So we will build the loft floor this summer to provide ample room for a small tv/living area , bedroom. We already did a 3/4 bath last year-which is kind of cool to have in my garage anyway!

We thought we might end up building a log garage afterall - as a wildfire has been burning in our little NM community & got way to close our place. They seem to be gaining on it & as long as the winds don't get crazy - hope to have it contained by Friday.

[twidget]

Just thought I would add a bit of info.

I built a starplate cabin in 1985. It is still standing up well.
I used 10' 2x6's. It has withstood the snow loads of western NY with no problem. I have seen up to 2 feet of heavy lake effect snow, on it.

The 2X6 makes 6" of fiberglass insulation easy to install. About the only thing would be to have a good vapor barrier to stop drafts.

Also put a good foundation under it as it will last for a long time.

good luck

Twidget

[travcojim]

Just curious if you have done anything more with your starplate? We are thinking of doing the same thing with 12' struts but after seeing your posts about 16', we were curious if you had done anything more.

[adz]

Wow...this brings back memories,
I did just this very thing about 30 years ago...but I used two "pods" connected with a center section / living area, about 16' in length.

I used to subscribe to Mother Earth News since the 70's.

[miltonjoy]

We are building in (Central East Alabama) a temp stick frame very loosely following Mother Earth news "build this cozy cabin" plan. We have added a 1/2 story to this plan and now it is tall and narrow...it just evolved into this. People have told us it will blow over or fall over in high winds. The dimensions are 14'X24' it is built on 12" sonotube piers below the frost line on southern hard "red clay" with a 6X6 "Timber rim foundation" around the perimiter sunk threaded rod and bolted down. It will have a 5/12 pitch roof with ~6" overhangs. It is platform framed. Has a height of 21' from the roof to the ground. The regional winds in Alabama here are 5-6 miles/hr. But the local winds seems windy and stormy alot. My husband is about ready to take off the top floor. There are no codes out here, so we just built it. We are building with 2x6 walls and plan to use plenty of hurricane straps and osb. My husband has some framing experience and using lots of reference books. So my question is is this thing going to fall over? Just trying to get debt free fast...or slow...Any advice is appreciated. here is a link. Thanks, Joy
http://i414.photobucket.com/albums/pp227/joygoround/cabin/2010023.jpg
http://www.motherearthnews.com/multimedia/image-gallery.aspx?id=74398&seq=1

[miltonjoy]

We are building in (Central East Alabama) a temp stick frame very loosely following Mother Earth news "build this cozy cabin" plan. We have added a 1/2 story to this plan and now it is tall and narrow...it just evolved into this. People have told us it will blow over or fall over in high winds. The dimensions are 14'X24' it is built on 12" sonotube piers below the frost line on southern hard "red clay" with a 6X6 "Timber rim foundation" around the perimiter sunk threaded rod and bolted down. It will have a 5/12 pitch roof with ~6" overhangs. It is platform framed. Has a height of 21' from the roof to the ground. The regional winds in Alabama here are 5-6 miles/hr. But the local winds seems windy and stormy alot. My husband is about ready to take off the top floor. There are no codes out here, so we just built it. We are building with 2x6 walls and plan to use plenty of hurricane straps and osb. My husband has some framing experience and using lots of reference books. So my question is is this thing going to fall over or blow over? Just trying to get debt free fast...or slow...Any advice is appreciated. here is a link. Thanks, Joy
http://i414.photobucket.com/albums/pp227/joygoround/cabin/2010023.jpg
http://i414.photobucket.com/albums/pp227/joygoround/cabin/2010024.jpg
http://www.motherearthnews.com/multimedia/image-gallery.aspx?id=74398&seq=1

[rreidnauer]

. . . but the structure itself looks like it should handle winds without issue. The weak point is the sonotubes. Are they strong enough? I don't know, but there are a few ways they can potentially fail.
1. Threaded rod could break out of concrete or tear out of wood structure
2. Due to low weight, sonotube may be pulled out of ground under high wind loading.
3. Depending on depth, sonotube may topple (especially if soil becomes softened like during torrential hurricane rains) and break up
Was any additional reinforcing rod added to the sonotubes before pouring the concrete? How is the threaded rod anchored into the concrete? Just stabbed in when it was wet? No "J" bend or anything?

[StressMan79]

I'd consider scrapping the top story, I would put in some guy wires. Basically just get some steel cable and some I-hooks and put a pad to fasten them to on both sides of the house, so the wires make ~45 deg with the ground. I'd do 3 per side. This might help you sleep at night, but if you put J bends on the threaded rod in the sonotubes, plenty of rebar and set them deep enough, there is very little chance that the structure will fail.
-Peter.

[Captn]

I'm with your husband ... I'd take off the top story to reduce the wind load ..... the other thing you can do is put out a few bucks to a structural engineer to get his opinion .... just a thought.

[loghousenut]

You're in Alabama aren't you. Look around you! Unless things have changed a bit in rural Alabama since I was last there 30 years ago, you have a well engineered mansion on your hands. No offense intended.

[StressMan79]

However, it is much worse. I have a shipping container that weighs roughly 15k#, topped with a lightweight shed. We call it the "penthouse." The structure is ~18 ft high and only 8 ft wide... and the only thing holding it down is the mass of the container. Wind loads are pretty low, however...I have no guy wires, and it has been fine for at least two years now.
http://i319.photobucket.com/albums/mm471/stressman79/DSC00189-1.jpg

[miltonjoy]

and rebar wire wraoped around the threaded rod, but no bend in the threaded rod. some have a washer with a nut at the end. So, it's not very anchored...don't ask. We used Home depot tubes so I think they were 4ft? 5ft? Some of it is sunk in 3 ft some are 18" in the ground.
Stessman, do you mean cable wire at the base of it attached to more concrete sunk in the ground? The penthouse is great, maybe we should have built that on our 40' hi cube.
I do want to make this something lasting for later on. But we plan on laying low for a year and really see if this is where we want to build a log house.
thanks

[StressMan79]

it is unfortunate that there is no bend in the rod, this will be the weakest part of the connection with the ground, the tubes won't fail.
the guy wires would go into something that is anchored in the ground. If you have a stump, that would be OK. Otherwise, sink some 10" tubes 3 ft deep, and put a loop of rebar out of the top of each, and then hook a wire to the top of the roof (or 3/4 the way up, put a brace across the two sides on the inside), through some eye hooks, then cinch it up taught (don't put 10,000# of tension in the wire, just don't let it slack). at the connection to the ground.
Anyway, the wire will effectively stop any side to side movement, at the same time, it will put downforce on the structure. If you have 500# of tension in each wire at 45 deg, you'll have 500#*6 wires.sine(45 deg) or just over 2000 lb downforce on the structure, at zero deflection. if the house budges even a little (say 1/2 inch) and you are using 3/8 inch wires, you have an additional force in each of the three wires on that side of
pi/4*d^2*E*deltaL/L0, say that L0=45'=540", deltaL = 1/2 inch, E (steel) = 30(10^6) psi and d=.375,
so the increased tension in each wire is over 3000#.
You then have 3x(3500-0)x cosine(45 deg) restorative force (the zero is b/c with a movement of half an inch, the the wires on the leaning side, will slack and no longer apply any force), or almost 7,300# of restorative lateral (side to side) force on the structure, also a total of 7300 pounds down force on the structure as well.
Also note the center of pressure is going to be half way up the side face. that is the place where you can put the effective point load due to the distributed wind loading. that looks to be roughly 8' off the tubes, but the restorative lateral force will be applied at the eyes, and will therefore have roughly twice the "moment arm." this means that 1 lb of wind load needs only .5 lb of cable load to react it.
I don't know what the size of your place is, but this means that you'd have to have zero strength in the rod, and have a wind load of roughly 14,500# to even lift the structure half an inch. In fact you need more than that, since the down force will also serve to counteract the wind load.
wind load is:
Force, F = A x P x Cd
Where A is the side area of the wall, P is the air pressure (due to wind) and Cd is the "drag Coefficient". P varies as the velocity squared, so a 10mph wind will have 100 x the wind load of a 1 mph wind. You'll see that to get P in PSF, it is .00256 x V^2, where V is in mph. For a flat wall, Cd is 2. I'm just guessing here, but your wall is roughly 15'high and 30' long, or 450sf, say you are designing for a half inch deflection in a 100mph wind, your pressure is then 25.6psf, and you get a side force of 23,000lbf. I would simply allow the deflection to be what it will in this unknown situation (we are ignoring the restraint of the tubes) and just get wire that can hold at least double the required for a 100 mph wind. A: you'll never see it, and B: 3/8 inch cable will easily hold this much load (you have 3 of them).Anyway, as you can see, guy wires are very effective means to stop top heavy or "unstable" structures upright. You'll notice every radio antenna has them all around

[Captn]

Beware of Hurricanes ...

I live in Texas ... Wind loading is our primary concern here .....

See what your max recorded wind speed is and design for a bit above that ....

[rreidnauer]

The sonotubes have rebar in them and rebar wire wraoped around the threaded rod, but no bend in the threaded rod. some have a washer with a nut at the end. So, it's not very anchored...don't ask. We used Home depot tubes so I think they were 4ft? 5ft? Some of it is sunk in 3 ft some are 18" in the ground.
Stessman, do you mean cable wire at the base of it attached to more concrete sunk in the ground? The penthouse is great, maybe we should have built that on our 40' hi cube.
I do want to make this something lasting for later on. But we plan on laying low for a year and really see if this is where we want to build a log house.
thanks

I'd be worried about the sonotube depths. The ones only 18" in really have me worried. That's not much soil to resist toppling, especially if there is more sticking out of the soil than what is in the soil. Wrapping rebar around the threaded rod doesn't do much either, though the nut and washer will help alot.
That said, it is just a temporary structure, and the house portion looks to be built plenty strong, so probably the worst that would happen is the piers would topple and the house would be sitting on the ground. Chances of actually being blown over, I think, would be far less likely. If it were me, and this is strictly just a suggestion, I would build forms and pour concrete walls in between the piers. (you could also ad additional threaded rods this way) That would lock the piers together making their collapse far less likely, as well as adding weight to the foundation lowering the (much slimmer) chance of the house toppling.

[miltonjoy]

We value your input. I think we have decided to take off the top floor just so any potential future buyers won't balk at the sight of our tower. I think we'll just add on to the sides for extra space next time with a j bend in the rods. Love you engineers and builders out there, you're such...what can I say...engineers and builders! Thanks
Joy

[ChainsawGrandpa]

Sounds just like a temporary cabin I built, except mine was 2' wider,
and 2' taller. Still standing after being hit with 60 mph wind storms.
G'pa

[akemt]

Chiming in a bit late, but I just got back on the forums (life took a twist --what's new!?). Sonotubes ARE a great option IF you do them correctly for your building, weather, and soil.

Here's a 14 x 24 that I'd love to build: http://www.countryplans.com/nash.html The website talks about how to insulate piers, etc. Best of luck!