IIT Bottle Top Bird Feeder With Hanger: DIY Guide

The IIT bottle top bird feeder with hanger is a kit that turns a used plastic bottle into a working hanging feeder. You screw the IIT feeder top onto a standard bottle, cut or use pre-formed feeding ports in the body, fill the bottle at least halfway with birdseed, and hang the whole thing from the integrated hanger. That's the core of it. The rest is about doing it right so birds can actually eat, the feeder doesn't spin or drip seed everywhere, and squirrels don't clean it out before sunrise.

What the IIT bottle top feeder actually includes

The IIT kit is designed around one simple idea: the plastic bottle you already have at home becomes the seed reservoir, and the IIT top replaces its original cap. The kit typically includes a feeder top unit (which screws onto the bottle neck), a built-in or attached hanger loop or wire for suspension, and feeding ports or openings built into the top or sides of the assembly. Some versions include a small tray or lip to catch seed so birds have somewhere to land and eat without flinging seed to the ground.

The bottle itself is not supplied because the whole point is reusing one you have. A standard 16 oz or 2-liter bottle both work, though a 2-liter gives you more seed capacity and means fewer refills. The feeder top controls how seed flows out, so the bottle is really just a gravity-fed storage tank. Understanding that relationship makes the whole assembly much easier to troubleshoot later.

What you'll need before you start

Gather everything before you begin. The assembly goes fast once you have it in front of you, but hunting for scissors mid-build is annoying.

• IIT bottle top bird feeder kit (the feeder top with integrated hanger)
• A clean, dry plastic bottle (16 oz, 1-liter, or 2-liter; wider bottles give better seed flow)
• A sharp craft knife or scissors (for cutting feeding holes if your bottle doesn't have them yet)
• A marker pen or pencil (for marking hole positions)
• A coin or washer as a sizing guide for the feeding holes (aim for roughly coin-sized openings)
• Birdseed appropriate for your local birds (black oil sunflower seed works for a wide range)
• A sturdy hanging point: a shepherd's hook, tree branch, or porch hook rated for at least 5–6 lbs
• Optional: monofilament fishing line or wire for extra hanger security
• Optional: a small plastic tray or saucer to catch fallen seed beneath the feeder

One note on seed choice: fine seeds like millet or nyjer can clog the ports faster than coarser seeds. Black oil sunflower is the most forgiving for a bottle-top style feeder because the seeds are small enough to flow freely but not so tiny that they pour out uncontrolled.

Building and assembling the feeder

This build takes about 15 minutes from start to finish. The main thing you can get wrong is the hole size and placement, so read through before you cut anything.

1. Wash and dry your bottle completely. Any moisture inside will cause seed to clump and mold quickly.
2. Hold the bottle upright and mark two feeding holes on opposite sides near the bottom third of the bottle. Opposite placement keeps the feeder balanced when it hangs.
3. Cut the holes using a craft knife or the tip of your scissors. Size them to roughly the diameter of a large coin. Too small and seed won't flow; too large and seed pours out without birds controlling the rate. If the IIT top already has integrated ports, skip this step.
4. Smooth any rough plastic edges around the holes with the back of your scissors or a nail file. Sharp edges can injure birds.
5. If your bottle doesn't have a perch, thread a short wooden dowel (a pencil works in a pinch) through two small holes punched directly below each feeding port. The dowel should extend about 3 inches on each side.
6. Fill the bottle at least halfway with birdseed before attaching the feeder top. Filling to at least half keeps enough weight in the bottle that it hangs with stability rather than swinging empty.
7. Screw the IIT feeder top firmly onto the bottle neck. Make sure it's hand-tight and won't unscrew from its own weight when hanging.
8. Turn the bottle upside down (the feeder top now faces down) and check that seed flows gently to the ports without pouring out in a rush. If it pours, your holes are too large; cover part of them with a small strip of tape and retest.

Attaching the hanger and choosing where to hang it

Connecting the hanger to the feeder

The IIT top includes a hanger loop or attachment point. Before you hang the feeder outside, tug the hanger firmly with both hands while the filled bottle is attached. The same basic hanger-tug and secure-connection checks also apply when you are figuring out how to hang an Mr. Bird WildFeast wreath. It should hold at least a couple of pounds without flexing or pulling loose. If you also want the hanging part to work reliably, follow these tips on how to make bird seed hangers so the connection stays secure. If the connection feels weak, reinforce it by wrapping a loop of wire or strong zip tie around the bottle neck just below the feeder top and threading that through the hanger loop as a backup.

Height and placement

Hang the feeder so the feeding ports sit between 5 and 6 feet off the ground. That height keeps it accessible for you to refill without a ladder, puts it high enough to deter ground-level predators, and matches what birds are naturally comfortable approaching. If you're mounting on a pole rather than a tree branch, Audubon recommends at least 5 feet off the ground with a cone baffle below.

Window placement matters too. Position the feeder either within 3 feet of a window or more than 30 feet away from one. That sounds counterintuitive, but feeders right next to glass don't give birds enough flight speed to injure themselves on impact, while feeders farther away give birds time to redirect before they reach the glass. The dangerous zone is the 4- to 29-foot range.

Stopping the spin

Hanging feeders almost always spin in the wind, and a spinning bottle feeder throws seed. Fix this by using two anchor points instead of one: run a second thin wire from a lower point on the bottle down to a nearby branch or hook at a slight outward angle. It doesn't need to be tight, just enough to dampen rotation. Alternatively, hang the feeder inside a covered area like a porch or pergola where wind is reduced.

Filling it right, bird access, and spillage problems

Always fill the bottle while it's upright (feeder top off), then screw the top on and invert it to hang. Trying to fill an inverted bottle through the ports is how you end up with seed on your shoes. Fill to at least half capacity so the feeder has enough weight to hang steadily, but leave a small air gap at the top so seed can settle without pressure-locking against the ports.

If seed is constantly spilling out without birds eating it, the ports are too large or the seed type is too fine for those openings. You can temporarily reduce port size by applying a strip of weatherproof tape across part of the hole and testing again. Sunflower chips and fine nyjer seed both tend to pour rather than trickle, so size your ports for the seed you actually use.

Balance is the other common issue. If the feeder leans to one side, the perch or the ports aren't symmetrically placed. Birds feeding from one side only will shift the center of gravity and cause the bottle to tilt. Rebuild any asymmetrical holes by patching with a scrap of plastic and cutting new ones directly opposite each other.

To reduce waste from dropped seed, place a small tray or saucer at least 5 feet off the ground directly beneath the feeder. This catches the overflow and actually creates a second feeding surface for birds that prefer a platform. Just clean that tray as regularly as the feeder itself.

Keeping squirrels and other pests out

No feeder design is fully squirrel-proof, and a lightweight plastic bottle feeder is an especially easy target. The honest approach is layers of deterrence rather than expecting one trick to solve it.

• Placement is your first defense: hang the feeder at least 8 to 10 feet from any solid launch point like a tree trunk, fence, roof edge, or building wall. Squirrels can jump surprisingly far horizontally.
• If you're using a pole mount, add a cone-shaped baffle at least 17 inches in diameter below the feeder and position it at least 4 feet off the ground so squirrels can't reach over it.
• Avoid hanging from tree branches directly, since squirrels will just walk down the branch. A freestanding shepherd's hook in the middle of an open area is harder to reach.
• For ants, apply a thin coat of petroleum jelly or use a commercial ant guard on the hanger wire above the feeder. Ants follow the wire down; breaking their trail keeps them off the seed.
• Don't use cayenne pepper in the seed as a squirrel deterrent. It can irritate birds' respiratory systems and isn't worth the risk.

Check the feeder and hanger hardware monthly for gnaw marks or chewed plastic. Squirrels will enlarge ports if they can grip the feeder, so any widened holes should be repaired or the bottle replaced before it becomes a full spillage problem.

Cleaning, seasonal upkeep, and when to replace parts

How to clean it

Clean your feeder at least once a month, and more often in hot, humid weather when mold and bacteria grow fast. The cleaning process is straightforward: disassemble the feeder top from the bottle, empty any remaining seed, and wash both parts with warm soapy water. Then soak everything in a solution of 9 parts water to 1 part bleach for 10 minutes. Rinse thoroughly until you can't smell bleach at all, and let both parts air-dry completely before refilling and reassembling. Never put seed into a damp feeder.

A bottle brush is the right tool for scrubbing the inside of the bottle where seed oils and debris stick to the walls. The ports and around the feeder top threads are the two spots most likely to harbor mold, so pay extra attention there. If the plastic has developed a grey or black discoloration that doesn't scrub off, it's time to swap in a new bottle. The IIT feeder top is reusable; the bottle is replaceable for free.

Seasonal adjustments

In winter, check the hanger wire and the feeder top connection monthly. Cold temperatures make plastic brittle, and a cracked bottle neck won't hold the feeder top securely. If the feeder top feels loose or the bottle shows cracks around the neck, replace the bottle before the feeder comes apart mid-hang.

When to replace components

The bottle should be replaced any time it cracks, discolors badly, or develops an odor that doesn't wash out. Because bottles are free, there's no reason to keep a compromised one in service. The IIT feeder top itself is more durable, but inspect the hanger attachment point and port edges every few months. If the hanger loop shows stress cracks or the connection to the top feels loose, reach out to the manufacturer or replace the kit. A feeder that drops from 5 feet onto a bird or a pet is not a minor inconvenience.

If you get interested in other hanging feeder formats beyond the bottle-top style, many of the same placement and hanger principles apply to seed bells, seed wreaths, and other DIY designs. The core logic of height, launch-point clearance, and regular cleaning carries across all of them. But the bottle-top feeder is a genuinely practical starting point: low cost, easy to clean, and simple enough to rebuild in 15 minutes if something goes wrong. If you want a more festive project, you can also use similar hanging-feed basics to make a Christmas wreath bird feeder that attracts birds during the holidays.