My house is very small. It was built in 1921 and has survived multiple large Southern California earthquakes. It's long history of being a rental in a quake zone has imparted some...quirks into the architecture. There are many impractical built in units that don't really provide adequate storage for anything modern. (Like the shallow cupboard that is built between two studs in the wall, low to the ground - what?!)

In my never-ending want to create more ways to store stuff in my tiny sardine can of a living space, I decide to build this over-the-toilet shelving unit for my bathroom.

Working with PVC is a cinch. It's like affordable structural tinker toys. The pipe is cheap, and you can get some really cool fittings from companies like Formufit.

The top is detachable from the base and could be used as a plant shelf or bookshelf for when I move out of this little place. (I like to change neighborhoods and apartments every few years, the joys of renting!)

Step 1: Tools and Materials

For this project I used the following:

Ratcheting pipe cutter
PVC chamfer & deburring tool
Measuring tape
PVC primer and cement
(5x) 10' lengths of 1/2" PVC pipe - best to get from your local hardware store
(10x) 1/2" furniture grade PVC tee joints
(18x) 1/2" furniture grade PVC 4-way elbow joints
(4x) 1/2" furniture grade PVC end caps
(3x) 9.25" x 24" x 3/4" choice wood board - I went to my local lumber yard for a 10' length of 9.25" poplar. I used a buddy's chop saw to make cuts, but most lumber places could make these cuts for you.
Drill/driver
Drill bits
Spade bits
(12x) #6 3/4" wood screws
Clear coat, matte, aerosol
Spray paint

Step 2: Making Cuts

I measured the space I am trying to build the shelf for and came up with the design that would require the following cuts to be made with a ratcheting pipe cutter:

(4x) 6" lengths for the feet
(9x) 20.75" lengths for the long horizontal supports
(14x) 6.125" lengths for the side supports
(20x) 10.5" lengths for the vertical side spacers
(4x) 4" lengths for the top (not pictured, because I forgot I would need them til I started gluing everything together :P)

Step 3: Dry Fit the Parts

I have made work where I don't dry fit, or test fit, parts properly and have wept many tears over having to redo work. These days, I know better....most of the time :)

But seriously, test fitting parts that are designed to tight tolerances and need to go in teeny spaces is key. My original design didn't compensate for how slanted my house is, so I ended up making two of the legs ever so slightly longer.

Step 4: Glue the Base

I needed the base to be rock solid to support the weight of the shelves and stuff I plan to put on top of it.

PVC cement doesn't mess around. It is very permanent and forms very strong chemical bonds. I like to assert an order of operations when it comes to assembling parts by marking up the dry-fit structure with a dry-erase marker. Tick marks help keep fittings square and wipe away easily after cementing is complete.

I worked with a clear primer to avoid gross purple marks all over the pipe. (yuck!)

Step 5: Add End Caps

Working with PVC caps is a great way to make a shoddy cut look nice and polished. :) Moreover, it prevents water and dirt from getting into the open pipe.

By adding end caps to the top and bottom of the shelves, we create level foot pads and completely seal the pipe from potential contaminants.

Step 6: Glue the Top Shelves

The shelves needed to be cemented along all the joints except along the axis where the set screw would be inserted.

The top shelf has shorter struts capped with endcaps.

Step 7: Making the Shelves

Cutting down a board is easy with a chop saw. I used a measuring tape and a square to make sure my cuts were the right length. If you don't have access to a chop saw (I don't, I used a friend's) ask the folks at the lumber yard to cut the wood down for you. Or use the tool of your choice! You have lots of options when it comes to making cuts in wood.

Measuring 1/2" from the side and corners, I marked out where I wanted to place the holes that the pipe would run through. Using a 1 1/4" spade bit, the holes were drilled. Ideally, you would use a drill press for this, but I just used my regular drill/driver and a piece of sacrificial board underneath.

Clean up the board with some 220 grit sandpaper on a sanding block before sealing. I prefer to use Matte Clear enamel, it really allows the wood grain to shine and yields a deep natural color.

Step 8: Adding Set Screws

Because one day I'll have to disassemble it, or may want to reuse the shelves in another configuration, I decided not to glue many of the joints and instead add set screws.

I learned about adding set screws to PVC from this Instructable by trevormates. It's a great way to make a temporary joint permanently stable, but not permanently glued in place.

I added set screws along inside vertical axis of the 4-way joints by drilling a hole through the fitting and the pipe and then adding a 5/8" woodscrew.

Step 9: Painting the PVC

Painting PVC requires spray paint that is designed to bond to plastic. Plastic paint used to come in a really limited amount of colors, but now it seems like you can get every shade in the rainbow.

I prepped the whole surface of the pipe and joints for painting with 220 grit sand paper, and then wiping with a tack cloth.

Working over a drop cloth I sprayed the entire surface with a layer of paint. After 20 minutes the paint is ready to be handled and moved to cover more of the unpainted area.

I waited 20 minutes between coats and rotations and applied 2 coats.

If you need to touch up your paint after more than a few hours have elapsed since your last coat, its best to wait 48-72 hours to reapply, otherwise your base paint layer can flake or crackle.

Step 10: Reassembly

Reassembly happens tier by tier. Re-registering the holes takes a few minutes, and banging the pieces into place with a dead-blow hammer will take some muscle.

Insert the set screw and slide the shelves on between layers so that the shelf is nested on the pipe fitting.

The pipe fitting's tolerance isn't designed to compensate for a few layers of spray paint, so I wiped the tip of the pipe and the inside of the joint with a little bit of machine grease on a towel to make the parts slip more easily.

Step 11: Voila!

That's a wrap!

This shelf fits in my tiny wacky house perfectly and helps me keep my bathroom more organized. (See the bottom two images to take a look at some of the features I had to build around.)

The unit is 100x stronger than I expected to be and has got me thinking what else I could structurally build for my house.