How to Build a DIY Compost Bin from Pallets

Fall produces more compost material than any other season: leaves, spent garden plants and more kitchen scraps as cooking moves indoors. A loose pile in the corner of the yard will break down eventually, but it sprawls, invites pests and looks messy the whole time. A bin made from wood pallets fixes all three problems for very little money, since pallets are often free and already have most of the structure built in.

Quick answer: Use four heat-treated (HT) pallets in sound condition. Set a stake or post at each corner on bare soil, screw three pallets to the posts to form a U, and hinge the fourth as a gate with a latch. Line the inside with hardware cloth if rodents are a concern. Start with coarse material at the bottom, then layer about two to three parts browns to one part greens, keep it moist and turn it every week or two.

Project Overview

Detail	Estimate
Size	About 4 × 4 ft inside, 3–4 ft tall (with standard pallets)
Capacity	Roughly a cubic yard or more of material
Difficulty	Beginner
Build time	2–4 hours
Main costs	Pallets are often free; posts, screws, hinges and hardware cloth are the main expenses

What You’ll Need

Materials

• 4 wood pallets of similar size (5–7 for a two-bay system)
• 4 wooden stakes or short 4x4 posts, about 4–5 ft long
• 2½–3 in exterior-rated screws
• 2–3 heavy-duty exterior hinges and a hook-and-eye latch or barrel bolt
• Optional: ½ in hardware cloth and heavy staples, zip ties for a quick build

Tools

• Drill/driver
• Sledgehammer or post driver
• Level, tape measure
• Work gloves and eye protection

Step 1: Choose Safe Pallets

Stamp or condition	Meaning	Use for compost?
HT	Heat-treated	Yes
KD	Kiln-dried	Generally fine
MB	Methyl bromide fumigated	No
No stamp	Unknown history	Only if you know the source
Colored (blue, red) pallets	Usually rental pallets	No, they belong to a pallet company
Chemical stains or smells	Past spills	No

Always ask before taking pallets from a business. Choose ones with solid slats and blocks, without rot or large splits.

Step 2: Pick the Site

• Bare soil, not concrete or a deck, so water drains and worms can move in.
• Partial sun: enough warmth to keep the pile active without drying it out.
• Convenient but not too close: near the kitchen door or garden, but not right beside the patio or a neighbor’s fence.
• Level ground makes the build much easier.
• Room to work: leave space in front for opening the gate and a wheelbarrow.

Step 3: Set the Corner Posts

Lay out the pallets on the ground in a square to mark the corners. Standard North American pallets are about 48 × 40 inches, so the bin won’t be perfectly square unless your pallets match; that’s fine. Drive a stake at each corner, about 12–18 inches into the ground, and check that each is plumb. In loose or sandy soil, go deeper. The stakes carry the pallets, so they need to be solid.

Step 4: Build Three Walls

Stand a pallet against the back pair of posts and screw through its frame into each post at the top and bottom. Repeat for the two side walls, so the three pallets form a U. Where two pallets meet at a corner, screw or zip-tie them together as well as to the post. Check the walls are plumb as you go.

Step 5: Hinge the Front Gate

Attach the fourth pallet to one front post with two or three heavy-duty hinges so it swings open like a gate. Add a latch on the other side to keep it closed against wind and animals. The gate makes it easy to add material, turn the pile and shovel finished compost out from the bottom.

A simpler alternative: slide the front panel between pairs of stakes so it lifts out, or use removable horizontal boards that you add as the pile grows.

Step 6: Line It (Optional but Worthwhile)

Staple ½-inch hardware cloth to the inside of the three fixed walls, and across the bottom under the pile if rats or voles are common in your area. It keeps small scraps from falling out and keeps rodents from getting in, while still letting air through.

Step 7: Start Filling It

Lay a few inches of coarse material, like twigs or straw, on the bottom so air can move up through the pile. Then add material as you collect it, mixing plenty of dry “browns” such as fall leaves with kitchen scraps and other “greens,” and keep the pile about as damp as a wrung-out sponge. Open the gate every week or two to turn the pile with a fork.

What to add, the browns-to-greens ratio, hot vs. cold composting and fixing smelly or slow piles are all covered in our beginner’s guide to composting at home. This guide sticks to the bin itself.

Expand to a Two- or Three-Bay System

Once one bin fills, add a second bay by attaching two more pallets that share a wall with the first. Fill one side while the other finishes, then turn material from the active bay into the next. A three-bay system (new, active, finished) keeps compost coming steadily.

Troubleshooting the Bin

Problem	Likely cause	Fix
Rodents getting in	Gaps in walls or open floor, exposed food	Line walls and floor with hardware cloth; bury scraps
Walls leaning	Stakes too shallow	Drive stakes deeper or add a second stake per corner
Gate sagging or hard to open	Light hinges or a rotting pallet frame	Use heavy hinges; add a block under the free end
Material spilling through slats	Wide gaps between boards	Add hardware cloth or extra slats on the inside
Pallets rotting	Normal after years of damp contact	Replace individual pallets as needed

For smells, a pile that won’t heat up or one that stays soggy, see the troubleshooting table in our composting guide.

Using Finished Compost

Finished compost is dark, crumbly and smells earthy. Shovel it from the bottom through the gate, screen out large pieces and return them to the pile. Spread it on beds in spring, mix it into raised beds, or top-dress around perennials.

FAQ

Are pallets safe for a compost bin?

Heat-treated (HT) pallets are generally considered fine. Avoid MB-stamped pallets, pallets with chemical stains or smells, and rental pallets.

How big should a compost bin be?

About 3–4 feet on each side holds enough material to heat up well. Smaller piles break down more slowly.

Do I need a bottom on the bin?

No. Bare soil lets water drain and worms move in. Add hardware cloth underneath only if burrowing rodents are a problem.

How long until I get compost?

With a well-managed pile, a few months. A casual pile can take closer to a year.