Owner built modular house

[BigMish]

Background: It has long been a dream of mine to build my own home. What has prevented me is money: I can't afford to pay my current home mortgage, new land payments and pay for construction. I got what I think may be the solution the other day: an owner built modular home that I build on my current property and then can break into modules, ship separately and reassemble.

Solution: I would build a series of 4 8'x18' bays in accordance with these specs (http://www.tinyhousedesign.com/2010/08/19/road-limits-for-tiny-houses-on-trailers/) that could then be moved on a trailer such as this (http://www.equipmenttraderonline.com/find/listing/2010-Sure-Trac-8.5-x-18-ft.-%289,990-lbs.%29-Low-Profile-Deckover-96587682). Here is a sort of example of how these would look: http://www.sherpacabins.com/bedroom.html

I would build a pier foundation (that is the same height as the trailer bed)  on my current property and, once the house was done and the land bought, on my new property.  I would then individually skid each bay onto the trailer with a winch, tow them to the new land and finally skid them off onto the new foundation. Once they were all in place I'd reattach them all.

Questions:
• Is this crazy? It seems to me not but I just want a sanity check before I begin going further with this.
• How would this work with building codes? I don't know when my land is yet so I don't know what codes to follow!

Note: I want to use a trailer that can hook up to my pick-up truck both because a larger trailer would have trouble getting into my back yard and because it would give me greater flexibility and independence .

I'd appreciate any thoughts or advise.
Best, M

[glenn kangiser]

It could be done but I would keep them in small enough units to be able to move them with yourself and what helpers you may be able to get.

I would wait until the land was a sure thing.  Your materials will deteriorate if just in the weather, or else have them indoors.  They could be in the way until your land purchase was finaled.

Usually this stuff is easier to do onsite and time wise you may not gain much.  How about making a list of materials and stockpiling them?

[BigMish]

Yea, that could work but at my pace it'll take me a couple years to go from foundation to moving in!

My plan includes having all of the plumbing and heating installed (as well as the electrical chases prepped for site install of electric once the modules are re-attached).

[MountainDon]

I'll be the wet blanket I guess.  

I would think this method will cost more than building on site as an owner builder. For one, you have the foundation you need to build it on and a foundation you would need to move it to.

Assuming you would be building under a permit, if you don't have the land you have no idea what the building permit department is going to approve or will require. That's too iffy for me to even contemplate.

How about putting cash, as it becomes available, in a savings account until such time that more details are nailed down and you can form a timeline.

That's my opinion.

[BigMish]

Sensible (maybe too sensible!).

I appreciate the frank advise.

.M

[MikeC]

A more basic "modular" possibility:

http://www.countryplans.com/cody.html

[MartyM]

I completely agree that the land needs to come first.  Having said that there are some circumstance's that I feel  give your idea some merit.

I have been kicking around a similar plan.  I have some land thats over 8 hours away one way. Im a single dad and just cant find the time or money to make that drive worth while. My curent scheme  is to use a  8 x 16 ft trailer to build a box with a simple shed roof. This is phase one and can be built in my backyard. The trailer would be just a kitchen, bath and a sleeping dormer. http://www.tinyhousedesign.com/wp-content/uploads/2009/04/8x16-tiny-solar-house-plans-v2.pdf  I would place the door on the high wall instead of one of the ends.  Phase one would be a fun place in the woods to spend a week or a weekend and I could just leave it at that..

Phase two if time, money and interest all come together would be to build a concrete block foundation to put the 8x16 box on. Im thinking large enough to hold a cisturn and a bit of a root  cellar.  The basement is set into the hill and bermed on three sides this will raise the south  or the high wall of the shed disign to about 20 ft.

The 20ft south wall sets the stage for phase three. Phase three would be a 12x16 shed roof attached to phase one, built on a slab.  Some thing like this    http://countryplans.com/smf/index.php?topic=5034.msg62759#msg62759  On a smaller scale.

I have been meaning to draw up some floor plans and post it for help tweaking the idea. 

[Don_P]

Some other alternatives;
Get a copy of "The craft of modular post and beam" by James Mitchell. Some good ideas in there.
Timberframe, fit it up at home and transport the parts
Log, same as above

Depending on the economy and inflation it can be cheaper in the long run to take out a note and purchase materials. I built ours on the pay as you go plan. I think it would have been cheaper to take out a relatively short term loan than pay the ever rising prices of materials. In my line of work that would have been mighty risky so it was only in hindsight that I know I could have made the payments, clear sight does not guarantee perfect vision.

[rick91351]

I guess my question is why not just find a small camp trailer on Craigslist or the want ads?  Set it up in the spring and pull it out in the late fall if you need to.  (We have to because of snow.)  From that trailer you can get in your septic and water, cellar and sheds or what ever property calls for.  

Or have you thought about SIPs?

Something like http://www.countryplans.com/cody.html

 

[Squirl]

I have seen some instances where this is viable. I have done something similar myself.  The problem is most people have a 8 hour a day job and have maybe 4 hours per day to spend time working on their house.  Many times the area where we want to build is hours away from where we are.  It would be great to buy a piece of property, go to work, then come home and work on the house.  But most times affordable land where we want to live is in the country, not near our lucrative jobs that can pay the bills and give us disposable income.  Then driving up for a weekend can cost over a hundred dollars and you only get a day of work in.  Therein lies the conundrum.    A possible solution is to build it at home and assemble it on site.  The 20x30 house seems like the most viable and what I have seen many on here.  I built in small 4ft sections that could be assembled on site.  Depending on where and how you drive, 8 ft sections can be difficult to get down the road and I was always worried about getting hassled or causing and accident. I noticed in the article they put the caveat "most U.S. states."  I would hate to drive through one where they could harass or ticket you. My max preference would be 6ft, but I am no trucker.   Finishing touches such as electric and plumbing usually have to be assembled on site. 

There are a dozen different ways to accomplish something.  Maybe you could prefinish the walls and stand them up on a triangle (like they do with windows) and trailer them in. Check with your local building department about their inspection process.  Some are a six step process from the footing, to foundation, to the framing, to the electric, to the plumbing, to the insulation, to the CO.  Also if you currently live in a town, if you pre-build a standing structure, someone from the building department might want to get paid.

SIP's are good too.  A few years ago I saw a 2 bed room 800 sq. ft. kit for $8,000.  A 3 person crew and a crane could get it dried-in in a long weekend.  Check with your build department ahead of time.  They aren't always approved.

[JRR]

I am a "wet blanket" on this modular scheme also .... wouldn't want to do it myself ... have already been thru projects where I lived and worked at point "A", and then on weekends or vacations, drove miles/hours to the work site, point "B".  NOT GOOD!

And then, after some reflection, I thought better of the modular concept ... it might be NOT GOOD FOR ME, but it might be the best for some folks.  Some might have idle time (on work week days, winter months, etc) at their home, their point "A", that could be used for sweat-equity if there is some efficient method.  Some procedure is needed to do the "assembly work" at home, and only the "installation work" at the building site.  Obviously a work area is needed, best if out of the weather ... but the home site is not out of the weather so, perhaps just "space" is needed.  And a plan that works for the individual.

The work shown in the link by Cody is great and the results are very nice looking.  Those modular panels look rigid and well made, but too heavy for me to put into place without rigging. Shipping would be a problem for my rather small trailer.  So what would make the modular concept workable for an old geezer like me?  If I "had to" ... I would do the following:  (I should have made some sketches, hopefully I can draw a sufficient word picture.)

1. Change the orientation of the module-panels.  Lets assume we want to end up with 8' foot high walls, then imagine pre-framed modules stacked one atop the other to make the 8' high wall.  If there are no windows involved, two 4' high modules would be the obvious choice.  If there are windows in a wall section, the separation line would be the bottom of the window ... say, a 5' high module atop a 3' high module.  The best way to plan this out is to take the elevation views of each exterior wall and draw in rectangular wall-sections that you wish to pre-frame into modules.  The horizontal length of the module-frames can be as long as you can manage.
.
2. Don't install sheathing on the modules.  The exterior sheathing adds a bunch of shipping/lifting weight to the modules, .... and possibly could be purchased separately close to the home site.  The final 8' sheathing, placed vertically, will tie our modules together.  The module-frames need to be kept square during shipping and installation... a sheet of 1/4 ply can be sliced into 4' by 4' squares, that will make fairly light shipping dunnage squares.  I would install on interior of module framing.  These dunnage pieces stay in place until sufficient exterior sheating is installed to prevent the modules from coming apart.  One per module section, installed with decking screws, should be sufficent.

This method obviously adds costs...but might make the module concept workable for some.  The modules, without the sheathing, should be easier to store outside without rain puddles forming.  I would use 2x4s to keep the weight low.

[Don_P]

That would put a weak hinge in the middle of the wall height. The studs need to be continuous from plate to plate or some other form of reinforcing would be needed... an engineered solution.

Except for the far west and high wind areas it would not be hard to frame something that would pass prescriptive code anywhere, the code does not vary that much across the country. I've built for companies that supplied nationwide, the vast majority of the builds were the same wherever we were, I just built to exceed code and had no problem with the inspectors.

[JRR]

That would put a weak hinge in the middle of the wall height. The studs need to be continuous from plate to plate .....

Good point, but I believe not necessarily so ...  unless the constuction is sloppy.  Each module would have its own upper and lower plate ... completely boxed.  If the studs are aligned upper to lower and all studs are properly anchored to its plate .... and the two joining plates are attached to each other properly, there should be no loss of structural integrity.  

Consider the lower frame module box ... with its lower plate attached to a platform floor (ply flooring attached to joists), and its upper plate attached to its companion plate belonging to the upper module.  Are the two plates not mirrow images of each other?  How does the upper plate know to perform differently from the lower plate?
.
.
Of course, if this logic does not convince the local establishment and make them comfortable... one could always add a Simpson strip that ties the upper and lower studs.  Not necessary to my mind.

In regular construction, the upper and lower plates must be secure ... or they will also "hinge".
.
.
If the two plates, attaching the modules, cannot resist the bending moment ... eliminate the two middle plates and add a sister-patch to each stud set.

[Don_P]

The studs in a wall are columns with the load of any floors above and the roof sitting on that column. If you saw through the middle of the column and patch it back together it will not be as strong as the unbroken column. The plates at the top and bottom of the wall are attached to lateral bracing, the floors or ceiling joists and plywood. Those diaphragms brace the top and bottom plates, your midpoint plates have no bracing. If you brace your midpoint splice adequately then it can work but this will take space. The splice will work but without an engineers blessing expect to make them full height.

A gable wall is balloon framed for this reason. One way to think about a wall resisting the wind is to turn the house on its side and view the wall as a floor resisting gravity. You wouldn't nail 2 halves of a floor together without checking the girder that keeps that connection from sagging and failing. Although the wind is typically giving only about half the thrust that the floor recieves, this is a sizeable force to be resisted. I've been in this situation with tall thin gable walls, the engineer suggested horizontal LVL's to reinforce the wall and just like with a girder under a floor the end reactions of the LVL's needed to be accounted for and taken to ground. It can work but I think its a tough row to hoe. I'd stand the studs up full height.

We are also trying to outthink the easiest, fastest part of the build. I can usually stand the walls of a small building in a day. Getting out of the mud is slow, then later, once my feet leave the ground things slow down dramatically. These are the areas I would think hardest about streamlining.

[JRR]

The studs in a wall are columns with the load of any floors above and the roof sitting on that column. If you saw through the middle of the column and patch it back together it will not be as strong as the unbroken column. ........... make them full height.

A gable wall is balloon framed for this reason. ............... I'd stand the studs up full height.

We are also trying to outthink the easiest, fastest part of the build. .....

I agree with essentially everything you are saying.  I would also choose to use full height studs ....and avoid modules altogether.  But modules might be the only way some folks can progress ... to use idle time to get something done.  Not the most efficient, or the easiest ... but a way for those folks with time constraints to "get the ball rolling"!

I prefer balloon framing over platform framing "thru out" ... but it doesn't lend itself to the concept of small manageable modules.  I want to, at the moment, accept the concept of modules and try to make beneficial suggestions ... if I can.  Yes, a patched together stud/column will normally not be as strong as the "unbroken" stud/column ... but I believe I could come very close using glue and screws.  I also want more than code ... so my question is "How can we exceed code building with modules?  In the current question, perhaps we should add interior sheathing.  That should make the module wall strong enough for hurricane resistance.

[Don_P]

One path to affordable construction is to choose your battles, or avoid them if at all possible. I'm assuming our unknown inspector is going to enforce the code. He is probably going to say he needs an engineer's stamp if the studs are notched more than 1/4 depth, these are cut in half. I'm pretty sure that an engineer will require more work than you are envisioning. The costs potentially just went up a good bit. Standing a panellized module up full height avoids the whole issue.  There are panellized suppliers that do ship nationwide, that's what they do.

Dad started working in the shop for these folks in '59 and went out on his own doing post and beam on site a few years later. They were both viable approaches. He has panellized several times when there has been good reason, the last time was north of Moscow during Febuary, inside a shop looked real good  .
http://www.deckhouse.com/partnership/systems_panelized.html.

For a simple box with a shed or gable roof it would be easy to precut the major framing and have it stacked on a trailer ready for a blitz build.

[MountainDon]

http://countryplans.com/smf/index.php?topic=4782.msg96549#msg96549

[NM_Shooter]

Yes, the blitz build worked for me.  Just to clarify about that picture that Don posted, I already had the floor framed and decked, and I had the roofing materials on site and tarped.  I framed the wall sections in my garage in the morning before work. 

I was sweating bullets that I had all the components that I needed; I am a 2.5 hour drive to the closest large building supply place.

I hired three out of work framers to come up and knock this thing out over the course of two weekends.  They worked all day Saturday and a half day Sunday.  At the end of that time I had a fully assembled, roofed, and hardi-board covered structure ready for paint.  I don't remember the exact amount I paid them, I think it was roughly $2500 total.  It was important for me to get the thing dry as fast as possible, as we get lots of rain at my cabin site. 

Ditto to others who said to get the land first.  Your building plans might change based on the type of land you end up with.  Land first, cheap trailer second, garage you can live in third, then home of your dreams!   

Good luck!