With a baby in the family, we found ourselves having a hard time trying to fit the stroller, emergency kit, groceries, and everything else you put/store in the trunk of a vehicle. We looked online and found shelf options for our vehicle, but they ranged in price from $300 to $375 (USD). Pricing out the materials, I was able to construct a two-piece shelf for approx. $90.

Materials Used:

Cardboard large enough to cut a template
2'x4', 0.5" thick plywood, qty 2
1"x3" pine board, 8' length
1.25" construction screws
Wood glue
5' length of outdoor carpet, 6' width
3/8" T50 staples
Exterior paint

Tools Used:

Skill saw
Straight edge
Tape measure
Pencil
Utility knife
Scissors
Heavy Duty (T50) Stapler
Driver

Step 1: Template

Using a large piece of cardboard, create a template for the location where you shelf will sit. If you're lucky, the space will have mostly straight edges. In my case, the area had a lot of curves. This meant I had to create reference points all along the way in order to properly account for the shape.

You want the template to be exact as possible, while accounting for a 1/8" gap all along the edge. This gap will be needed for folding the carpet over the edge of the shelf. You want the carpet folded over the edge to reduce any rattling or scratching of wood against plastic.

Step 2: Trace and Cut

Instead of one large shelf, we chose to do two pieces. This gives us options for having one or both pieces. You can also add a hinge between your pieces.

Leave a 1/8" gap between the two pieces of wood to allow space for the carpet. Trace your template onto the wood. You may want to mark reference points on the wood to ensure your template is mirrored on both sides as exact as possible.

Using a skill saw, cut each piece. Be as exact as possible. Test fit each piece in the vehicle and make minor adjustments where needed.

Remember, you can also make more cuts! Be conservative when making adjustments so you don't remove too much and end up with an unusable piece of wood.

Step 3: Remove Notches

The location for our shelf had notches for other accessories. For me it was easier to remove these after cutting the general shape. For you, it may be easier to mark their locations on your template.

These were easily marked from below. I then used a jigsaw to remove the sections.

After cutting the notches on each piece I did a test fit before continuing.

Step 4: Support

To prevent bowing, and allow you to place heavier items on your shelf, you'll want to put a cross support on each piece.

Cut a 1"x3" beam to the necessary length for each piece. Then attach using wood glue and construction screws of the appropriate length.

Step 5: Paint

While these will be covered in carpet, I didn't want to worry about the wood getting damage over time if they get wet from rain blowing in or something spilling on them.

Each piece was given two layers of the exterior paint. I chose a color that closely resembled the carpet color.

In addition, if you aren't planning on carpeting both sides of the shelf, the painted finish gives them a nicer look if you can seen them from below.

Step 6: Attach Carpet

For the carpet, I chose an indoor/outdoor option from the local hardware store. It can handle what we plan to put on it, and isn't too expensive.

Lay your piece(s) on the carpet and cut out the necessary shape using a utility knife or scissors.

Make sure you leave 3-4 inches of extra carpet on all sides for wrapping the edges.

I recommend a heavy duty stapler for this part. This is a stapler that takes T50 staples.

Attach with staples every four inches, or less. I recommend attaching one long edge first, pull the carpet tight, then both sides, and finishing with the opposing long edge. You may have to get creative with how you deal with all the odd shapes and corners.