Introduction: Tiny Shipping Container Home
Welcome to another kick-ass Instructable from Disc Dog! Today I'm going to show you how to make the most amazing tiny home from a shipping container. But first, a disclaimer: I build these tiny homes for a living, but not quite this simple. Mine all fold up in on themselves for transportation to anywhere in the world, where the ones I'm going to talk to you about don't, but if you read on you will find how easy it is to build a neat little tiny home out of a shipping container with NO SPECIAL METAL WORKING SKILLS REQUIRED! :-)
Before I go into the nitty-gritty of this build I am hoping that you have some good, basic carpentry, plumbing, framing and roofing skills (the kind of skills you'll need to build a home of any size). And if it seems like I am skipping a lot of detail, I am. This Instructable is long enough without going into all of the detail you would need to completely fabricate a tiny house inside and out, so this Instructable shows you the basics for a really cool tiny home, but leaves out a lot of steps for detail fabrication as well as interior designs. For each room I suggest you gather your ideas and wait for the step in this Instructable where you can insert them.
Because I am not going to build an actual tiny home like the one I am writing about here there won't be a lot of photos and examples of what I want you to do, but I will provide some sketches and dimensional drawings as needed; I think you'll see why and completely understand what you need to do to make the best darn tiny home imaginable. I promise not to leave you hangin', so if anything is unclear, or you have questions after reading through the Instructable completely, get back to me. Also, be sure to read through everyone else's questions before you send me a repeat question; that will help me in my response time.
I also won't go into a lot of detail for fabricating the interior of this tiny home because - quite frankly- that's the neat part of this tiny home...you can put any kind of interior you want. You can run the plumbing and electrical as you see fit after you finish this Instructable (but I will show you what I did) so keep that in mind as you start putting this tiny home together. Also, there is a lot of good ideas about insulation, interior finishes and storage for container homes on line so don't be afraid to do some homework before you start your build.
Final note: I build my tiny homes in shipping containers because [as built] they are hurricane proof. I'm probably the only tiny home fabricator in Florida that makes an extreme-weather proof houses.
Later on I will give you my website to compare what I'm doing to what you'll be doing (and a short-cut if you want one). Now, time to pick up your bag of hand tools and get crackin'!
Step 1: Find Yourself the Perfect 20' Shipping Container
You'll need to start looking for a particular type of 20' container: it's referred to as a 'side loader'. This is a factory built container that has a set of full-span bi-fold doors on one side of the container. These won't be easy to find used however, since most of them are owned by individuals to haul their cars and SUV's around, or by shipping companies to move individual vehicles around the world; they don't take the beating that most containers take by moving commodities from China so they tend to stay in service a lot longer. But I have seen them come up used every so often. If you can find a well used one please LOOK BEFORE YOU BUY.
Bottom line is that a new 20' SIDE LOADER will cost you about $5-$7,000. A used seaworthy one (not beat up and still serviceable) will cost about $3-$5,000, and a non-serviceable one will cost you about $2-$4,000. If you have the time (and patience) look for a good, used seaworthy container. You won't need to inspect it before you buy it. If you find a used, non-rated container I would be very leery about buying it. If the doors are sprung on their hinges, or the floor is trashed beyond use, you easily spend the difference in coin just to make it livable. Personally, I would just buy a new one. After all, this is probably the most important part of your investment in your house; why be penny-wise but dollar-foolish? Besides, the factory painting and anti-corrosion protection on new ones in phenomenal. If you don't scratch or dent the surface one of these will last 30+ years.
When your done building your 8'x20' container tiny home it will expand from less than 160 sq ft to about 200-250 sq ft of living space, depending on the side-door configuration and how you use them. The containers I use give me about 240 sq ft of living space. Unique to them is that the inner bi-fold doors are significantly larger than the outer bi-fold side doors, hence the large increase in square footage. Look around to see the differences.
I suppose you could just open up both doors to make a 320 sq ft tiny home, but the roof for that wold have to be more substantial that the roof I show in here.
Also, side-loaders come in both 20' and 40', but don't be dissuaded into buying a 40' one. They are a bugger to move around and cost an arm and a leg to relocate them. (Why do you think they are so cheap?) You can move a 20' container with a roll-back tow-truck or a pickup and roll-back goose-neck trailer (like I do), but a 40-footer need a semi and [usually] a crane to hoist it off. If you absolutely want the room of a 40 foot'er think about just getting (2) 20's and link them together. The small difference in coin will usually pay for itself in transportation, ESPECIALLY if you have to move it later on.
Step 2: Locating Your Tiny Home
It's not imperative that you set your container down on it's final resting spot, but it would make things a whole lot easier. The bottom line is that you will be building a roof, a floor and 2 door frames/structure for your container home and it is best to build them on, in or around the container after it is located. And what you want those structures to look like will depend on where you put your tiny home, so consider sight location before you consider cutting wood.
Also PLEASE look into zoning regulations before you make the final location decision; not all areas are modular or shipping container home friendly. Do not put it somewhere where it will need to be moved later on.
The cool part of shipping container homes is that they are considered 'modular' homes, and not 'mobile homes, and they already come on a permanent foundation, the skirt. If your building codes require that the home be set up on a permanent foundation then a simple 10'x22'x4" thk concrete pad will do you just fine. Locating modular homes is far less restrictive than tiny homes on wheels.
The other piece of information you might be able to use is that the dwelling is less than 320 sq ft. This is important because many cities, counties and states do not have restrictions on dwellings less than 320 sg ft.
If you want to anchor the container down in the event of tornadoes you can also sink four 1-1/2" - 2" diameter think-walled steel pipes in the concrete in the location of the stacking lugs. (The container is already Cat 3 hurricane proof just sitting on the ground). See the sketch for exact location dimensions. Before you set the pipes in the concrete be sure to screw a bolt or two in the bottom of the pipe or (if it's a threaded nipple) screw a cap on the end; this will give the concrete something to hold on to and not pull out. Also, put a 1/2" diameter (or larger) thru-hole near the top (this will give you a feature to put something into to anchor it down with). Set them in the concrete foundation with no more than 2"-3" sticking up; anymore higher than that could prove difficult to drive the delivery truck over.
Just make sure you have a level patch of 25' x 15' earth to put your container on. In a pinch even some undisturbed earth or a grass field will do. But if you do not put it on a concrete pad, just use a couple of those 3" thick 3'x3' concrete pads you can pick up in the garden center at Lowes or Home Depot to set your container on. They will make it easier to find 'level' that just grass. You can set it up on just grass, but it may sink a little over time and that may prove unfavorable later on down the road.
Or, if your patch of earth isn't too level, then just pour a few level concrete pads and set it down on that. You only need to set it down on the corners. If you don't have the skill or patience to do that. a local contractor can do it for you on the cheap.
Step 3: Start With the Building the Platform Floor
To build this floor you will need some rudimentary carpentry skills and maybe a few good power tools. You will be building an 'outdoor' style deck/floor supported on deck blocks. If you've never built a simple house floor or outdoor deck be sure to study up on it or find a good buddy who has. You should build it to code (minimum size 8x floor joists on 16" centers w/3/4" OSB/plywood flooring). You should also stuff it full of insulation between the floor joists. You can do this after you build the floor; flip it over, insulate it, seal it up and flip it back over. (Here's where it's helpful to have a buddy or two help you move the Platform Floor around.) It's a simple step but you should be as exacting and detailed in your construction as you can be. Attention to detail here will pay off in the long run.
After the container is set up permanently open up just the inside doors of the (4) Side Doors to be straight out. Leave the outside Side Doors locked shut. Try to get them exactly 90 deg out, but if your not exact don't sweat it. Now you will measure for the Platform Floor that you will build that the Side Doors sit on.
As stated above, this Platform Floor will be built just like a regular floor using 2x8 floor joist on 16" centers with 3/4" flooring over insulation between the joists. The Side Doors will sit on top of the Platform Floor with enough overhang to take advantage of the double-lip seals on the Side Doors. You can also lay down some tongue-n-grove floor panels on the plywood if you want a finished, wood floor.
To get these measurements you need to start by measuring the inside-to-inside dimension between the doors near the lip of the container. IMPORTANT: If you look you will see a double-lip seal along the periphery of the Side Doors you have opened. You want to know the dimension between the side doors up to BUT NOT BEYOND the exterior seal. To get this dimension measure is pretty simple: measure to the inside surfaces of the 2 Side Doors and add 4" (each lip seal is about 2" out from the inside edge of the doors). Using a permanent marker draw a small line on the lip of the container for a center line between the doors (and also write it down in case you wipe off the centerline).
The length of the Platform Floor (the distance away from the container) is going to be the length of the door(s) plus about 12". That will give you a good lip to hang out past the front doors.
You can build the floor in place by just swinging the Side Doors out wide enough to get access to the container, but before you do that be sure to measure and mark center on the container lip so you know where to locate the floor. It helps to build this in place because you will probably have to creep up on the right floor height.
As you build the Platform Floor and size the support blocks for it, the floor height should be about 1/2" below the bottom of the Side Doors and about 1/2" higher than the lip of the container floor.
You will see that the lip of the container floor has a slight drop in it (about 1/4"). If you make the floor height the same as the lip height your Side Doors will not 'sit' properly on the Platform Floor and there may be a gap between them.
Complete the Platform Floor and be sure to put a precise center location line on the edge of the floor that butts against the container lip. When you move the Platform Floor in place for the last time lining up these center marks will ensure your Side Door seals mate up perfectly to the outside of the Platform Floor.
After you build the floor you should be able to swing the Side Doors over the floor with minimal effort, however you want to see good compression of the inner door seal against the top platform floor and the outer door seal lay flush against the edges of the floor. Like I said, the Floor should be about 1/2" below the bottom of the Side Doors. This also should also allow you to put down some type of flooring (but you don't want to put it on at this step).
I'll go over what I recommend after you build the Entrance Door Wall. I'll also go over how to attach the Side Doors to the platform floor permanently a little later on, but for now just finish up your Platform Floor to your personal level of comfort for form, fit and function.
Later on we will also cover ways to get rid of that small lip you will end up where the floor meets the container as well.
Step 4: Building the Front Entrance Door Frame
Like the last step discussed, it helps to have some basic 2x4 framing skills, insulation and siding skills for this wall. Now is the time to plan for windows too if you want a more traditional front entrance.
First, pick out the front door you plan on using. If you haven't done so, now is a good time to go to some lumber liquidators or building surplus store and pick out a floor model or last year's model...or maybe you came across a closeout on a really cool door and bought it some time ago. If you're going to put a window in the Entrance Door frame buy the window first as well so you can make the frame to match. Now's the time to by first and cut lumber second.
I recommend a Home Depot Series 50 sliding glass door. Why a sliding glass door? Your container home is going to be naturally dark (since it doesn't have any skylights or other exterior doors/windows) so a sliding glass door really helps. If you visit my website you will see that the particular container I use allows for 2 standard 72"x80" sliding glass doors, so I use 2 of them. It's a big selling point in my tiny homes. Why Series 50? They can be put in place in pieces; first you assemble the frame and put it in place and then you slip the doors in. And they have a large selection of doors and screens. If you ever tried to put an assembled sliding glass door in a door frame you will know what I am taking about when I say "It ain't a cake walk, that's for sure".
To start framing your Entrance Door frame take some more measurements of the opening between the inside surfaces of the Side Doors snug up against the Platform Floor you now have located in place. (Depending on how square you made the Platform Floor this dimension may be a little different that the dims you took in step 1). Now, subtract about 1/2" from that dim; this will allow for some foam-strip insulation between the Entrance Door frame and the Side Doors.
After you have those dims you'll measure the distance between the top of the Side Door(s) to the Platform Floor. If it's a standard container the height should be 85" from top to bottom, and your floor should be about 1/2' below the bottom of the Side Door, so you should see about 85-1/2". But you'll want to measure it to be sure.
Write both dims down and frame up your Entrance Door wall with 2x4's. I would frame it up in a workshop (or garage floor). (You can do it in place if you don't have somewhere else close by to frame it up.). Give yourself about 1/4" clearance on all sides for both the door and window frames so they are a good, slip fit.
After your done framing it up, locate the Entrance Door Frame by centering it on the Platform Floor with about 3" of inset from the edge of the Side Door(s); attach it to the Platform Floor with nails or screws. Be sure not to let the frame tilt over; use braces as necessary.
Then, with the Door Frame secured to the floor, attach it to the Side Door Frames with 4 hefty construction angles, one near the top and near the base of each side. See the sketch.
The reason I recommend using angles is that once you fastened the Entrance Door frame in place is that you can still unfasten it to open the Side Doors and open them up if need be. And it makes it a lot easier to put insulation in place along the edges of your finished entrance door wall. It never hurts to think about leaving your options open during your next building step.
Using 1-1/2" long [min] screws secure the angles into the wood of the Entrance Door frame first, then use some 3/4" to 1" long self-drilling/tapping hex head screws to secure to the Side Doors. Like I wrote above, after you have screwed them in you can take the self taping screws out and put them back in as you go along, but for now they will serve to secure the Side Doors, Platform Floor and Entrance Door Frame in place while you finish the door frame.
Now finish off the Entrance Door Frame in place by putting the outside siding in place, insulation and then the inside siding too.
Put the exterior siding and edge trim right over the angle clips attached to the frame but leave the part of the clips screwed to the Side Doors exposed. That way you can un-secure them if needed.
After that you can put the Entrance Door and any windows in and finish off the Entrance Door Wall completely.
If it's easier you can unscrew on Side Door at a time to work on the Entrance Door Wall. However, IF YOU ARE GOING TO UN-SECURE both Side Doors from the Front Wall at the same time BE SURE to brace or support it from falling over!
After you're all done with the Platform Floor and Entrance Door Frame you need to secure the Platform Floor to the Side Doors. To do this you'll need 4 ea. 3/8" U-bolts. (You can also use 5/16" if they come in a narrow, longer length). Secure the Side Door latching posts to the Platform Floor from underneath by using the u-bolts to go around the latching posts and above the latching pawls as shown in the sketch. Use Loctite or a jam nut to secure the nuts in place; tighten all nuts down very to a good, snug fit.
Step 5: Putting a Roof On, the Fit
There are probably a hundred ways to put a good roof over this tiny home, but keep in mind the joint work from the roof you're gonna build to the container roof has to be not only water-tight but have enough roof angle to get the water to run off. That's why a flat roof across the Side Doors is not my recommendation.
The Roof design is the basic metal barn-style insulated roof. You can buy all of the materials at Lowe's, Home Depot or most other large lumber supply houses. If you've never built a metal roof check out Youtube or just Google it. It's pretty simple. Or you can simple shingle roof it if you want, but IMHO it won't look as good, be as easy and will take longer.
For this roof design you'll build 4 roof perimeter support members, 2 [tapered] Roof Edge Supports that run along the top of the Side Doors, 1 End Cap that runs along the roof of the container above the lip, and 1 along the top of the Entrance Door wall. Then you'll put several purlings between the Edge Supports to nail the plywood to. There is a rudimentary sketch of what to expect above.
I dimension'ed this roof to fit over a containers with the larger middle Side Doors (about 82" long/wide). If your container has the shorter Side Doors (like 50"-55") you can use this roof but you'll have a lot of overhang over the Entrance door. Don't be afraid to cut it short (on the tapered end over the Entrance Door) if you want to, but if it was me I would just leave the overhang; it will save you from cutting metal.
For this first step you'll need:
2 pcs of STRAIGHT 8'x2"x8" boards for the Side Door Edge Supports.
First cut down (2) 8' 2x8's to the dims in the sketch above. Those Supports are based on using 96" long roofing metal with about 8" of overhang over the front of the roof trusses and 4" of overhang over the container roof. (You can normally buy the roofing metal in 8' lengths so I want to design the roof on those common dims. If you really want to you can cut down the metal roofing to shorter lengths but it is no fun [but I can tell you how to do it if you want]).
You might want to check the notch dimensions (the 2" x 3-3/4" cutout in the sketch) over the rain lip that I drew in; there's no guarantee that your rain lip is the exact same as mine, but you can get the gist of the need for the notch for it. The goal is to get the notch to fit around the rain lip and butt up against the face of the container under the lip of the container. Make a few test fits on your first Edge Support. Note that the Edge Support fits down in between the Side Door seals. If you can cut the notch to be a close fit even over the droop even better.
You will also want to make sure the cut/notched end of the Support (that overhangs the roof) is flush on top of the roof and DOES NOT OVERHANG OR SIT ON TOP OF THE CORRUGATED SECTION OF THE ROOF. You will see that the roof is corrugated along the top to keep water from sitting on it, however the corrugation ends about 3"-5" before the rain lip so make sure that the end of the Support Edge does not go into this corrugated section; your End Cap will need to sit flush AND SEAL against the roof under the End Cap. If you cut your Support to the dims I have shown, and it is too long, cut it down until it sits right.
Once you're comfortable with how your first Edge Support fits, duplicate it for the other side and test fit them up on the container roof and the Side Doors. You want to make sure they lay flat inside the Side Door seals, flat on the container roof and are snug up against the container under the container roof lip.
Now measure the distance across them (outside to outside). Add 6"-12" of over hang for each side and divide by 48". This will tell you how many 4x8 boards you'll need, and how many liner feet of roofing you will need. Be sure to write this dim down; it's too easy to forget or transpose two of the numbers and end up short.
Next step is piecing the roof together.
Step 6: Finishing the Roof Sturcture
The cross-sectional sketch above gives you the basic stacking order of a metal roof. I didn't put overhang dimensions in this view but you should have 6"-12" on both sides. Design the width of your roof to only cut the plywood to width, not the metal. If you metal roofing is 24" wide, make you roof width a multiple of 24"; if it's 36" wide (most common) then make you roof width a multiple of 36". Since you know the width between the Edge Supports you will start from there.
This is the longest step so read through it carefully first and ask questions before you start cutting if need be.
Materials; You'll need the following to make this roof:
3-4 sheets of 3/4" 4'x8' plywood/OSB; it all depends on how wide your roof is over the Side Doors.
6 pcs of 12' 2"x4" STRAIGHT boards; these are the purlings
3-4 sheets of 1/2" rigid insulation foam board (4'x8'); IF you use thicker insulation be sure to get LONGER roofing screws than 1-1/2"
1 roll of vapor barrier (15# roofing felt); use thicker for better noise suppression.
4-5 pieces of 36' wide x 96" (8') long metal roofing. (36" is the most common. If what you are using is less than 36" of coverage you'll need to buy enough to cover overall roof width)
3 pcs of metal roof edging (or drip rail). You'll put those over the container roof edge and the two outer edges.
Box of Roofing screws w/seals
A box of 3" construction screws
A box of 1-1/2" long wood screws
A roll of Perforated Galvanized Steel Duct Strap
A tube or two of window, door and siding sealant.
A tube of construction adhesive (like Liquid Nails or something similar)
Start by taking a measurement between the Edge Supports: Drop them both down in the Side Door seals (as shown in the sketches) and butt them up against the container. Tape them down to the top the Side Doors for now. From there you'll need to climb up a small ladder and take a decent measurement between the inside surfaces at the ends of the Edge Support sitting ON THE CONTAINER ROOF. (Don't trust the Side Doors to be square to each other just yet.)
Write it down; you'll be duplicating it exactly for your purlings and End Cap. (If you have a container with the big Inner Side doors it will probably be somewhere around 159 1/2" or so.)
Pull the Edge Supports back off and lay them in position on a large, flat surface.
Cut up your End Cap and 4-5 purlings to the same exact length and then secure them to the inside, and FLUSH to the top surface, of the Edge Support (as shown in the dimensional sketch) with the 3" construction screws.
You'll note that construction screws have drill bits in the end of them so no pre-drilling necessary. This also helps keep the wood from splitting, especially if you are screwing into the ends of purlings.
Keep the purlings and End Cap vertical and on 16" (or less) centers even if the last one [at the tapered end] is a bit closer. You may need to rip down the top edge of the End Cap and one of the purlings to fit flush with the Support Edges and not rest on top of the inner seals of the Side Doors. Use only two construction screws for each side (least you split the wood). You should end up with a framed roof support truss structure that looks like the sketch.
You may wish to stain or paint the interior and exterior of the roof truss structure if you don' plan on putting siding on it (or an interior roof on it) afterwards.
From here you'll need to get the help of a friend or two to help you put it back on top of the Side Doors.
Put some sealant on the end notch that butts up against the container and under the End Cap (that goes over the Container roof) first, then locate the truss on the Side Doors (between the Side Door seals as shown) and slide it back until it has firm contact with the container's exterior. Use the Perforated Galvanized Steel Duct Strap as Hurricane Strap to pull down and secure the roof to the container's Side Doors as shown. (Here you can use some 1-1/2" wood screws in the Edge Supports and some self-tapping metal screws in the container Side Doors). Put at least strap one per side along the front of the roof and one per side along the back of the roof as shown in the sketch(s).
Put some more construction sealant along the mating surface of the roof truss End Cap and the roof of the container and then use at least 3 construction angles to secure the roof truss End Caps to the roof of the container; 2 near the ends of the Edge Cap and one in the middle. Look for good squeeze out of the sealant so you won't have roof leaks inside after you're done. Seal off all edges along the container roof and roof truss structure. The double door seals on the Side Door will keep water from getting inside the Side Doors.
Once your roof truss structure is secure go ahead and start placing the 4x8 3/4" sheathing down. Leave about 4"-6" of overhang over the container roof.
Don't forget: it is best to keep the overall width of the roof a multiple of the same width (or slightly less) as your metal roofing so you don't have to rip one of them down to size. Be sure to leave about a 1/8" gap between the 4x8's to allow for expansion.
Start by securing one 4x8 with the desired amount of overhang on one side of the Side Doors Edge Supports and lay them out until you have only one 4x8 to rip down to size if need be. Use the 1-1/2" wood screws to secure the 3/4" plywood to the Edge Support joists and the purlings; use a screw every 12"-16".
After you're done putting the sheathing down be sure to finish up the exterior of the roof truss structure before you go any further. If you're going to paint, side or stain the structure now is a good time to put it in place.
Step 7: Putting on the Roofing Metal
After you have finished the roof truss structure and have the plywood in decide what kind of roofing you want. Like I wrote earlier, I instruct on using a metal roof but now is as good as time as any to go to shingles or fiberglass.
For this step you will also need 1 each 5 Gal. Siliconized and Microcell Elastomeric White Reflective Roof Coating
Use a little construction adhesive (or a staple gun) to tack the roofing felt down as well as the rigid insulation boards before you screw the metal roofing down.
You will need a power driver (drill) and a hex-head driver bit for the metal roofing screws.
Be sure to secure the metal roofing down squarely and with proper overlap between each panel. See the picture on how to screw the roofing down. Note: try to hit the purlings to secure the roof; it will keep the tips of the screws from showing underneath on the underside of the roof. Also, as shown above, make sure you go through the crown of the metal roof corrugation as shown above, and not the trough.
Finish up with the metal roofing edge caps and sealing the roof against the container, even under the container roof lip. You don't want any water migrating under this joint.
Wash the roof of the container thoroughly before you put down the rubber roof coating. Apply the coating to the manufacturer's recommendation. The 5 gallon pail will have more than enough to put down one or two good coats, and I would definitely use it all up because in this case 'the more the better'.
Step 8: End Wall and Door
I have included a drawing of a frame and a few pictures for the End Wall and Door that I use on my containers. You will see from the pictures that it's a good place to put in all of your utility connections, such as power, water and sewer. I also use this wall design because my bathroom is just on the other side, and the kitchen is attached to the bathroom wall for reasons of easy, concealed plumbing. I stuck a screen shot of my CAD drawing to give you and idea of how my bathroom and kitchen are arranged. (Go to my website bbpods.com if you want to see a 3-D representation of this bathroom)
If you want to duplicate what I did you'll want to build your wall as I did.
First, measure the inside dimensions of your End Door opening. (It should be real close to what I have drawn.) Frame up your End Wall to go flush with the inside frame of the container. You will use 2" long wood screws to secure it to the floor and a few construction angles along the side and top to secure it to the container. Then, just use some sealant along the joinery work to keep the drafts and bugs at bay.
You will note that I put a 16"x32" window in my End Walls because it's a great place to have one if you put a full-size bathroom on the other side.
I also framed my End Wall up to accept a standard 32" wide storm door. If you make you bathroom skinnier you can use a wider door but I'd rather have a larger bathroom than larger side door.
To make this frame duplicate the framing steps in Step 5. Put the exterior siding on place but don't finish the interior of the wall until you get your bathroom designed and fabricated in place.
Step 9: Interior Features and Planning for Neat Things to Have (like a Bathroom and Kitchen)
You will probably want to put some interior features in next, such as insulation, electrical, interior walls, etc. before we call this Instructable quit, so here are some good tips and ideas. Also, read the next step first before you start thinking about this step; it may give you some good ideas.
After you finish framing the End Wall you should insulate the interior and then put some walls up on the inside of the container before you finish the End Wall and put the rest of your house together. Here is what I have learned:
You can use the spray-on foam insulation but it's expensive (and messy) so I like to use rigid board insulation. You can also use fiberglass roll-out insulation too, but if you do space your studs for the width of insulation that you buy (it comes in both 24" width as well as 16"). ALSO, if you use fiberglass roll-out insulation PUT YOUR STUDS on edge instead of flush (as pictured). If you don't it's darn near impossible to compress even R13 insulation down enough to screw the walls to them.
The rubber roof you put on a few steps ago will serve well as roof insulation; it will keep it cool in the summer and provide a reasonable amount of insulation in the winter. You can glue up some rigid insulation boards on the roof and/or also put a drop-down ceiling on the inside for the ultimate in insulation. It's up to you.
About them studs....
Before I put up the insulation I put up a few wall studs, but I put them in the horizontal [instead of the vertical]. I then cut down the rigid foam board to fit between them. And if you use 3/8" bead board like I do then you only need two along the interior; one about 1' up from the floor and another about 7' up from the floor (you will see a lot more that than in the photo above...this was one of my first builds and afterwards I figured I really didn't need all of those studs for 3/8" unfinished bead-board; it's stiff enough to get by with just two.) If you're going to use sheet rock for your interior walls then you might want to put 4 instead of just two. Put them on 24" centers and use 24" wide insulation.
The studs are easy to install if you follow these steps:
1) Pencil a few marks at each end of the inside walls at the height you want your studs at; for two sets of studs 1' and 7' work good. (the 7' stud is a good place to hang murphy beds, heavy cupboards and shelves from).
2) Snap a chalk line between the marks and drill out a set 3/16" holes along the chalk lines on every third interior-protruding ridge. You'll know you're drilling on the right surface because it will be the only one with a chalk line on it.
3) Have a buddy hold the studs against the wall from the inside and [using the same metal roofing screws] secure the studs from the outside. Using the sealing screws so they will seal up the exterior surface.
4) Plan out your electrical and plumbing before your go any further, then run your electrical and plumbing along the backside of the studs before you insulate and seal up the walls. I ran all of my electrical along the top stud and just dropped electric lines behind the studs in the cavity created by the corrugated walls.
Those spaces are a great place to run electric and plumbing because you can insulate right over them and they are shielded by the studs if you drill into the studs with a 1-1/2" or shorter drill bit.
If you have never wired up a house you should really call in a friend or expert for this step. Of every build section of this tiny home that you can make mistakes on, this part of the build is not one of them. Please run your wiring to electrical standards for wire gauge, breaker size and outlet type.
I didn't relish the idea of hooking up to 220 Volt/100 amp residential service to a 240 sq ft tiny home, so I wire up mine for 110V/50 amp service. But that also means no 220 V appliances.
Now here are some tips and ideas about finishing up the interior of your tiny home:
Vent your bathroom plumbing up to one of the 4 exterior vents you will find along the top of the backside of the container so your tiny home doesn't smell like the boy's locker room after 'Burrito Night' every time you use the head. You can just glue an electrical outlet box around it and plumb 1/2" PVC to it and to the plumbing off of the bathroom sink.
Seal up the Side Door hinges with a couple of finished (stained and/or painted) 1"x5" boards cut down to about 85" and glued in the gap between the large Side Doors and the small Side Doors [you left shut]. You can also Velcro these board in place but they won't be air-tight. (I use a flexible rubber seal on my joints but my tiny homes are designed to be open and closed repeatedly.) You can also position a piece of plastic 3"x5" gutter down-spout cut down to a snug fit and then just frame around it. That will keep the weather of the inside framing and provide some insulation as well. I've also used Hyperlon (inflatable boat material) to form a type of Freezer Seal around them.
Don't be afraid to use your imagination when it comes to sealing up these gaps, and if you come up with a novel or clever way let us all know!
On to the bathroom...
As you saw in the previous step I fabricate my bathrooms like they do for mobile homes: modular, upside down and on a work-bench. Depending on how you run your plumbing and electrical you can finish up the entire floor for the bathroom floor and just hook up the electrical, plumbing and sewer as you slide the module in place.
Look to your local RV store for hook-ups and just mimic how they do it. I use a 50-amp plug and standard RV sewer connections for mine.
Hang a propane powered 'tankless' instant hot water heater on the back wall of the bathroom wall and plumb it to the kitchen sink, the shower and the bathroom sink.
Just clean up the floor, sand out the rough spots and throw a couple coats of outdoor decking water seal on it. A 1 gallon pail give you years of coatings.
Tuck a 3.1 cu ft mini fridge under a gas cook top (converted to propane) mounted on a standard 24" x 48" counter top;, then plumb the cook top & hot water heater to a full-size propane bottle you keep under the kitchen sink.
Step 10: Your Finished Product
Here I will showcase one of the typical 'IKEA' style interiors. (This was for a tiny cabin) You can always go to them for ideas but don't be afraid to think outside the box. If you visit my website (www.bbpods.com) you will see all types of arrangements and get a lot of ideas of how you can make your tiny home one cozy place.
And thank you for visiting my latest Instructable. If you like what you read vote for me in the Tiny Home Cotest!
Second Prize in the
Tiny Home Contest