Concrete and Pipe Shelves

I am currently working hard to create my dream office space and love how it is turning out! It is a little bit rustic, a little bit industrial chic and a little bit fancy. It is the perfect space to get creative in and I can’t wait until it is finished! You can read more about it in my post about craft room inspiration.

One of the projects I was excited to work on was to build a shelf unit for one wall in the office. This wall isn’t very large and is between two windows but it is the perfect place to add a little storage and a little personality to the space. I love industrial styles, and so after a lot of thinking and an evening in my favorite store (The Home Depot), I came up with plans to make these beautiful concrete and pipe shelves!

Materials

• 2 — 1-in. x 2-in. x 8-ft. Melamine Boards
• 3 — 8-in. x 36-in. White Melamine Shelves
• 6 — ½-in. PVC Pipe Couplings
• 1 lb —2½-in. Gold Screws
• 6 — 5/16-in. Zinc Washers
• 6 — 5/16-in. Nuts
• 6 — Plastic Bags
• Clear Silicone Caulk
• Caulking Gun
• Olive Oil
• Paper Towels
• 14-gauge Welded Wire
• 80 lbs Countertop Concrete Mix, grey
• 5-gallon Plastic Bucket
• Trowel
• Wire Snips
• Piece of scrap board approximately 18″-24″ long (we used a scrap 1-in. x 2-in. we had lying around)
• 16 — Triple-Grip Drywall Anchors (holds up to 100 lbs)

Pipe

• 4 — ¾-in. Black Malleable Iron Threaded Floor Flange
• 5 — ¾-in. Black Malleable Iron Threaded Tee
• 6 — ¾-in.Black Malleable Iron Threaded Coupling
• 5 — ¾-in. Black Malleable Iron Threaded 90 Degree Elbow
• 3 — ¾-in. Black Malleable Iron Caps
• 8 — ¾-in. x 2-in. Black Steel Threaded Nipple
• 4 — ¾-in. x 5-in. Black Steel Threaded Nipple
• 4 — ¾-in. x 3-in. Black Steel Threaded Nipple
• 6 — ¾-in. x 8-in. Black Steel Threaded Nipple

Tools

• Compound Miter Saw
• Nail Gun with 1½-in. Brad Nails
• Electric Sander
• Gloves
• Electric screw Driver and hand screw driver
• Level

Step 1: Build the Molds for the Concrete Shelves

Our concrete and  pipe shelf design consists of three concrete shelves, each measuring 24-in. long and 6-in. wide. To make these, we built three molds using melamine shelf boards for the bottom of our molds and 8-ft. pieces of 1-in. x 2-in. melamine board for the sides. We cut the 1 x 2’s into (6) 24-in. lengths and (6) 7½-in. lengths. If you are careful, (2) of the 1-in. x 2-in. boards will be sufficient to make three shelf molds.

We attached the 1 x 2 side pieces of our mold to the melamine shelf bottom using our brad nail gun.

In order for the piping to go through the concrete shelves, the concrete shelves need holes at both ends wide enough for the steel piping to pass through. To create these holes we used PVC couplings to create a negative space in the mold where concrete would not go.

In order to locate where to place the couplings in the mold, we assembled the steel piping section that would pass under and through the concrete shelf. Then we traced the locations on the mold where the pipe would pass through the shelf with pencil.

We attached the PVC couplings to the mold at the traced locations in the following manner.

We wrapped each coupling in a plastic baggie first.

Then we used a washer, nut, and screw, as shown in the photo above, to secure the coupling to the mold. We needed the nut for spacing to keep the screw from going all the way through the mold. We wanted to create a tight seal between the coupling and the bottom of the mold so this was the best way we could think to ensure a tight seal.

Next, we used silicone caulk to seal all inside edges of the mold and let it dry completely.

Coming later in this process, we’re going to add wire reinforcement to the concrete. Since the concrete dries pretty quickly, you’ll want this wire reinforcement cut and ready. While the caulk is drying is a good time to prepare your wire reinforcement. We used wire snips to cut the rabbit fence into (3) pieces approximately 22-in.  x 4½-in. in size, and set them aside.

After the silicone caulk was dry, we coated the entire inside of the mold with olive oil to help the concrete release from the boards when it was ready to come out.

Step 2 : Mix and Pour the Cement

Next, we mixed our cement in a 5-gallon bucket. I used a my drill and a mixing paddle attachment to make this part easier.

You want to mix the concrete thin enough that you can easily pour it into the mold and ensure it gets in all corners and spaces. We found that somewhere around a thick toothpaste consistency worked well, but you can vary it a bit to your preference.

We filled half the mold with concrete and then placed our pre-cut rabbit fence into the wet cement.

We then filled the rest of the mold with cement.

We used our scrap 1-in. x 2-in. board to smooth the top of the concrete by running it along the top of the mold in a back and forth motion. This removed any concrete that was above the top of the mold, creating a flat surface. (This will be the bottom of the shelf but we still wanted it to be nice and flat.)

After the molds were filled with cement and the top was leveled, we tried to get as many air bubbles out as possible. We did that by placing the electric sander without sand paper along the sides of the molds. We let it run for several minutes to let the vibrations of the electric motor encourage the bubbles to surface. The longer the sander ran the more air bubbles came up in each area.

Then we used our 1-in. x 2-in. board to remove any excess concrete again.

We cleaned off all excess cement from the edges of the molds and then set them aside to dry.

If you are in a particularly dry climate, I would consider covering your shelves with plastic while they dry so that they don’t dry too fast and crack. Indiana is pretty humid right now, so we just let them sit in our garage.

Step 3 : Remove the Concrete from the Molds

After three days, we carefully used a flat-head screw driver to loosen the side boards of the molds.

Be careful that you do NOT put any pressure on the concrete edges when doing this or the concrete might crack. But you can apply pressure to the other molding boards.

You will only need to loosen these side boards, you do not need to remove them completely.

Then we unscrewed the PVC couplings.

And then we gently removed the concrete shelves from the mold and popped the PVC coupling out of the concrete shelf.

The concrete shelf was molded upside down, so the part that was against the melamine board will actually be the top of your shelf.

If you want a smooth finished look, you can sand your concrete and fill in any holes with a concrete filler, wait for it to dry and then sand and buff it. But we wanted a rough industrial look, so we did not sand or fill the shelves. We really love the imperfect look it gives. It is not a finished countertop look, but it is perfect for this project.

Step 4: Assemble the Pipe Shelves

After our concrete shelves were created, we began to assemble the shelving unit!

I like to wear gloves when working with metal pipe as it is a bit dirty, but that is up to you.

To make it easier, use this image showing where all the pieces go. This reflects what the final pipe layout will look like without the shelves. But you will actually assemble it one section at a time as shown below.

We assembled the metal piping into three separate sections, one for each concrete shelf.

Then we attached the concrete shelves to the metal piping using a metal coupling on one end and a metal end cap on the other.

We left the three shelf sections separate at this point because they are very heavy, and it would be too difficult to install the entire shelving unit at one time. We attached one shelf unit at a time to the wall to make installation easier.

Step 5: Mount the Pipe Shelves on the Wall

Now comes the part where you definitely will need a second set of hands to help lift and hold each shelf unit up as you mark, connect, and mount it to the wall.

We began with the middle shelf because I wanted to ensure the placement of that shelf, but in retrospect, if we did this again we would begin installation with the bottom shelf instead. So I recommend beginning installation with the bottom portion of the shelf first.

We held one shelf section up to the wall and marked the location of the screw holes for both metal flanges. We had one flange under the shelf and one above. We used a level to make sure the shelf was horizontal.

Once the holes were marked, we set the shelf back down on the floor while we installed drywall anchors in each of the flange hole locations. If you happen to be placing your shelf unit into a stud, you won’t need anchors, but because ours was not being placed into a stud, these anchors will provide the support needed to keep our shelving unit safely on the wall.

After the anchors were in place, we attached the shelf section to the wall.

This was a two person job. I had my husband hold the shelf up on the wall while I screwed the shelving unit into the drywall anchors.

Next, we marked the location of the flange screw holes for the next shelf section. There was only one flange for this section but we still marked the screw locations and installed the wall anchors as we did above.

To connect this section to the shelf unit already installed on the wall, we twisted the threaded nipple as far as we could into the threaded tee connected to the flange on the wall. Then we connected the second shelf section to the threaded nipple and twisted the threaded nipple several times. This step is a little tricky because as we tightened the threaded nipple to the second shelf section, we were also loosening it from the threaded tee connected to the flange. So we just twisted the threaded nipple a few times to ensure that the two shelving sections were connected.

Another option would be to connect the entire unit on the floor and have two or more really strong friends come over to help hold the entire unit up while you screw it into place. But this unit is just too heavy for two people to do on their own that way.

Since it was just myself and my husband installing this, I had my husband hold the shelf up while I connected the two sections together and installed the screws for the second shelf section.

We repeated this process to attach the third shelf section to the wall.

Then we added a few decorations and couldn’t believe how beautifully this turned out!

It is heavy! But sturdy. And it’s the perfect accent to my industrial chic or rustic studio office!

And because it is near two windows, it is the perfect spot to sit and read, check out a design magazine or just take a break for a few minutes!

Here are a few more photos because I just couldn’t resist!

And in case you’re wondering, you can find all the details on that cute Gold Arrow Marque that I created on my blog.

I’ve made a few other shelving units for my home including these floating shelves and ledge shelves, but I think these industrial chic concrete and pipe shelves are my new favorite!

We are completely in love with how this turned out and can’t wait to try our hand at another concrete project really soon!