Intro: DIY 4X8 Micro-Tiny House Camper on Harbor Freight Trailer
I got this idea from a multitude of TLC shows. I did homework on this for quite some time before pulling the trigger. Using a little luck and a combo of other Instructables and whatnot, we tossed this together in about 2 weeks of working evenings.
Step 1: Intro
A lot of simple tools were used to make this and I dont have the exact count on materials. The total cost was around $1100 (trailer included). This was done as a fun thing, so we didn't really follow plans very closely, just kinda winged it.
Step 2: Assemble Trailer
This trailer was on sale at Harbor Freight for $250. Has the 1500lb axle and when completed weighs nothing close to that.
I used a motorcycle wrench and a crescent wrench. I eventually went back and impacted the bolts together.
The instructions in the manual were complete trash, so I would recommend a Youtube search to help you out.
I made sure to leave the fenders and the lights off so they would not get in the way while building.
Step 3: Plywood and Frame
After the trailer is set up, attach the 1/2 in plywood as well as the 2x3 frame to the trailer frame. I used a bunch of carriage bolts through existing holes in the trailer frame instead of drilling into it myself.
It is important to tighten the carriage bolts reeeeeeally tight in order for the screw heads in the corners of the trailer to bite into the wood. If it isnt tight enough you will have a small gap between the plywood and metal frame. (thank god for impact drivers)
Clamps totally help out here.
Step 4: Frame
The next step was to make the frame. Measurements change depending on which window(s) you choose and where you want to put them. I went with 28x39 storm windows from home depot. They were around $30 a piece. You'll note that there are only 3 sides here. I wanted to make my door swing all the way open and be able to attach to the outer wall so that I could double this trailer as a motorcycle hauler, so the door will be the size of the entire back wall.
Step 5: Attaching Sides to Base
I started by attaching the front wall using 3 inch construction screws. I used an awful lot of them to ensure intregrity. It is super important to keep checking your square with a speed square. Levels aren't very accurate because of the trailer moving, so I would definitely recommend a square. Once The first wall was on (and quadruple checked for square) the next two went on. Note that we staggered the windows so that they were on opposite sides and opposite ends. This was actually a mistake (a lot of Natty was used in the making of this), but once we realized it, I kind of liked the idea, so we kept it.
Step 6: Roof/Front Wall
As if it wasn't apparent from the photos, I do not have an indoor shop to work on this. Being as I live in SC and it rains almost every day, we had to go out of order and add the roof next. We measured to the center and added a 2x4 for a roof support. Plenty of liquid nails was added to the top of the frame to seal the roof from water.
Atop the 2x4 a 1/2 in thick 4x8 OSB was used. I Decided to use (2) 2x8 corrugated steel panels for the roof with a slight pitch above the door to keep rain from the door jam. To do this, I attached a 2x3 to the OSB directly above the door. Next, I used (2) tubes of roofing tar on top of the OSB to hold the steel down, then screwed the steel in. When secured (carefully) with roof fasteners, a nice slope was created in the roof for water to drain from.
The front wall was cut from a 1/2 in 4x8 piece of plywood and also sealed with Liquid Nails.
Step 7: Outside Sides and Window Cuts
Since I did a lot of guess work with the dimensions, I made the walls too high. They sit at 58" high, so excess plywood needs to be stitched into it to make it whole. If I were to do it again, I would keep it at 48" so (1) panel would cover without cutting. Before the walls were installed they were test fitted to the frame and the window frames were traced so we could cut them with a circular saw on the ground instead of a recip. saw on the frame. Even though the storm windows bolt to the outside and would hide any mistakes, this makes for cleaner cuts.
I needed to rip a 10" x 8' section of plywood to finish the bottom of the wall. I used liquid nails to attach to the frame and fill the seam. Once that dried, I spackled it in on both sides two times.
Once the windows were cut, more liquid nails was applied to bond the wood, then screwed in place.
Step 8: (Optional) Insulation
I used (2) rolls of pink panther insulation on all 3 walls before I put up the inside panels.
Step 9: Inside Paneling and Second Floor
In other instructables I saw people use underlayment. I decided to just use 5/16 plywood. The same procedure as the outside was used. Cut window holes with circular saw, add liquid nails to panel, attach panels to walls.
The interior roof is made of a cheap, ugly 4x8 panel board. I did this to make it easier to see if water leaked. It is cheap and easy to tear down. Luckily I haven't had any leaks yet. Paint hides the grossness of this board at the end.
I also added a 4x8 osb to the floor on the interior. The plywood alone felt too springy, so the OSB was added for support and ground insulation. It also reduces the dip created by the thickness of the frame.
A spot was left open in the front corner to install a cabinet.
Step 10: Back Door
The back door is attached using (3) 8 inch hinges. The frame for the door is made of (1) 2x3 for the hinges to attach to, and the rest are 2x2. 5/16 in plywood is the paneling. Liquid nails and caulk attach it to the frame.
On top and bottom I stapled a rubber door trim to keep water out
Step 11: Paint and Trim
This bad boy has 3 coats of outdoor paint and primer. The paint is thick enough to hide the ugly seam. It also doubles as a protection from water and elements.
Metal trim with a drip edge was used on the two long sides. The front and back are a 4in 90 degree flashing. I offset it with some scrap osb so that water could drip off of the roof and underneath it.
Excess 4in flashing was cut with tin snips and used to hide the 2x4 riser mentioned earlier to put the roof pitch in.
Step 12: Windows
Storm windows bolt to the outside of the window. We caulked the living hell out of the back, and slapped 'em on the wall.
Step 13: Interior Paint, Base Coat and Cabinet
I used the rest of the outdoor paint as a base coat to fill any gaps on the inside. The drop out cabinet was also put in place to test fit. I used quarter round (only tacked in place for now) to trim in the seams.
Step 14: Paint, Trim, Window Sills and Carpet
After removing the trim, I painted the interior blue. Ceiling stayed white to create the illusion of depth.
Outdoor carpet was installed and tacked into the floor.
Using excess plywood, a window sill was painted, caulked and installed on both windows.
At this point (hard to see in pictures) I also attached 4 anchor points to the frame so I can ratchet strap my motorcycle in it if need be.
Step 15: More Paint, Trailer Wiring and Back Door.
Using the remaining plywood, the inside of the door was paneled. I added handles to help open it. There is also a hasp on the inside to lock it while I sleep. Hooks were added to the inside of the door to help with storage. I left the bottom not paneled so that I could mount a trash can to it.
At this point I ran all the wires for the trailer lights and all. Since the door can open all the way, I opted out of adding fenders.
Step 16: Pull Out Bed
I wanted a custom couch/bed that was light and easy to remove. I came up with a sliding do-dad that also doubled as a storage unit. The panel is 4x4 underlayment.
Step 17: Bed Pad/Finished Project
When compacted, it takes up less than 3 feet. Expanded, it is the size of a twin bed (exactly). I used an old mattress pad and sewed a cover on it. There are (2) three foot pads that cover the bed when it is expanded. The front door is attached by a chain to the ceiling so you can pack stuff inside it in travel. It is actually very spacious under there.
Also pictured here are (2) telescoping pvc awning poles. I sheathed (2) 5 foot pieces of 3/4 in and 1 1/4 in pipe together and added holes in increments. A bolt with a wing nut lets them move up and down. Pictures of the awning deployed will be coming soon.
Main take aways- caulk
If you do this for yourself and have any questions, I will be more than happy to try and help.
Thanks for reading