Squirrel House — Complete Guide
Plans, dimensions, placement, and everything you need to build a squirrel nesting box that actually gets used — from a 30-acre Michigan wildlife habitat.
Two fox squirrels sharing a wooden nesting box — exactly what a well-placed squirrel house looks like in use
Squirrels are some of the most entertaining wildlife you can attract to your backyard. But here's what most people don't realize: squirrels struggle to find safe nesting spots. Dead trees with natural cavities are disappearing from suburban landscapes. That's where a squirrel house comes in.
A well-built squirrel nesting box gives them a safe place to raise their young, escape predators, and survive harsh winters. And unlike a bird feeder that needs constant refilling, a squirrel box is a one-time project that benefits wildlife for years.
Why Build a Squirrel House?
Squirrels need secure cavities to raise their young and survive winter. In nature, they use tree hollows, abandoned woodpecker holes, and leaf nests called dreys. But in developed areas, these options are limited. Homeowners remove dead trees. New construction clears old-growth timber. Squirrels are left scrambling for safe shelter.
Hawks, owls, snakes, and cats can't reach squirrels inside a properly built box. The 3-inch entrance hole is specifically sized to keep raccoons out.
Rain, snow, and extreme temperatures are deadly for baby squirrels. A solid wooden box keeps them dry and insulated through Michigan winters.
Female squirrels need secure dens to give birth and nurse their kits. A nesting box can support multiple litters per year — spring and late summer.
Unlike leaf nests that deteriorate in weather, a wooden squirrel house lasts for years with minimal maintenance. Cedar boxes can last 10–20 years.
Once squirrels move in, you might spot baby squirrels peeking out in spring. Learn what baby squirrels eat and how to help orphaned kits in our complete baby squirrel guide →
Types of Squirrels That Use Nesting Boxes
Different squirrel species have slightly different needs. Here's which squirrels will use a nesting box and what size entrance hole they need:
| Squirrel Type | Entrance Hole | Range | Notes |
|---|---|---|---|
| Eastern gray squirrel | 3″ | Eastern US & Midwest | Most common backyard squirrel |
| Fox squirrel | 3″ | Eastern & Central US | Larger body, same hole works |
| Red squirrel | 2.5″ | Northern US & Canada | Smaller, very territorial |
| Flying squirrel | 2.5″ | Eastern US | Nocturnal, often nest in groups |
| Western gray squirrel | 3″ | Pacific Coast | Less common in backyards |
If you're unsure which squirrels live in your area, start with a 3-inch entrance hole. This accommodates gray and fox squirrels — the most common backyard species — while keeping out raccoons.
Where Do Squirrels Nest?
Understanding where squirrels nest naturally helps you build and place a better squirrel house. Squirrels use two main types of nests:
Tree cavities — Their preferred nesting sites. Natural holes in trees, old woodpecker cavities, and hollow limbs provide excellent protection. Squirrels line these cavities with leaves, bark, moss, and fur.
Leaf nests (dreys) — When cavities aren't available, squirrels build nests out of leaves and twigs high in tree branches. These are the big clumps of leaves you see wedged in tree forks. Dreys work but offer less protection than cavities.
Squirrels prefer nesting sites 15–30 feet off the ground, in mature hardwood trees (oak, hickory, walnut, maple), near food sources, away from busy human activity, and protected from prevailing winds. This is exactly what you want to replicate with a squirrel nesting box.
Where Do Squirrels Nest in Winter?
Winter nesting is critical for squirrel survival. Unlike some animals, squirrels don't hibernate. They remain active all winter, venturing out on warmer days to retrieve cached food.
In winter, squirrels prefer tree cavities over leaf nests. Cavities provide better insulation and protection from snow, ice, and freezing rain. Multiple squirrels often share a winter den for warmth — you might find 4–6 squirrels huddled together in a single cavity.
If you install a squirrel box in fall, there's a good chance it will be occupied before the first snow. Squirrels actively seek out winter shelter as temperatures drop — fall is the best time to install.
To make your squirrel house more winter-friendly: add extra bedding material (dry leaves, straw), make sure the entrance hole faces away from prevailing winter winds, check that the roof doesn't leak, and mount it on the south or east side of a tree for morning sun.
Squirrel House Plans
Building a squirrel house is a simple woodworking project. You don't need fancy tools or expensive materials — just basic lumber, screws, and a few hours.
Materials Needed
- 1″ x 10″ untreated pine or cedar board (6 feet)
- 1 5/8″ exterior wood screws
- Drill with 3″ hole saw bit
- Saw, measuring tape, pencil, sandpaper
Never use pressure-treated lumber for wildlife boxes. The chemicals can harm squirrels and their young. Stick with untreated pine, cedar, or cypress. Cedar naturally resists rot and lasts longest.
Squirrel house building plans — cut list, dimensions, and assembled view
Basic Design Features
- Enclosed box with 3-inch entrance hole
- Sloped or hinged roof for rain runoff and cleaning access
- Ventilation gap or small holes near top
- Rough interior surface so squirrels can grip and climb
- No perch — predators use perches to reach inside
How Much Does It Cost to Build a Squirrel House?
| Material | Estimated Cost |
|---|---|
| 1″ x 10″ cedar board (6 ft) | $15–20 |
| Exterior wood screws | $5 |
| Total | Under $25 |
If you use pine instead of cedar, you can reduce the cost to $10–15 total. And if you have scrap wood from other projects, a squirrel house is essentially free. Compare this to buying a pre-made squirrel house ($40–80) and you'll see why DIY makes sense.
Squirrel Box Dimensions
Getting the dimensions right ensures squirrels actually use your box. Too small and they won't fit comfortably. Too large and it won't retain heat in winter.
| Part | Measurement |
|---|---|
| Floor (interior) | 8″ x 8″ |
| Height (interior) | 12–15″ |
| Entrance hole | 3″ diameter |
| Entrance height from floor | 8–9″ |
| Wood thickness | 3/4″ to 1″ |
Cut List for One Squirrel Box
| Piece | Dimensions | Quantity |
|---|---|---|
| Front | 9.5″ x 15″ | 1 |
| Back | 9.5″ x 18″ (extra for mounting) | 1 |
| Sides | 8″ x 15″ | 2 |
| Floor | 8″ x 8″ | 1 |
| Roof | 11″ x 12″ | 1 |
Why 3-inch entrance hole? A 3-inch hole is large enough for adult squirrels but too small for raccoons. This keeps predators out while giving squirrels easy access. For flying squirrels, use a 2.5-inch hole instead.
DIY Squirrel House — Step-by-Step
Cut Your Pieces
Using the cut list above, measure and cut all pieces from your board. Sand any rough edges but leave the interior surfaces rough so squirrels can grip.
Drill the Entrance Hole
On the front piece, mark the center of the entrance hole 9 inches from the bottom. Use a 3-inch hole saw to drill the entrance. Sand the edges smooth to prevent splinters.
Add Ventilation
Drill two 1/2-inch holes near the top of each side piece. This allows air circulation and prevents overheating in summer.
Add Drainage
Drill four 1/4-inch holes in the corners of the floor piece. This lets any water that enters drain out and keeps the nest dry.
Score the Interior Front
Using a saw, make shallow horizontal cuts on the inside of the front piece below the entrance hole. These grooves help baby squirrels climb out when they're ready to explore.
Assemble the Box
Attach the sides to the floor using screws. Attach the front, then the back (positioned so extra length extends above for mounting). Attach the roof at a slight angle for water runoff.
Add a Cleanout Door (Optional)
Hinge one side or the roof so you can open it for annual cleaning. This isn't required but makes maintenance much easier each fall.
Mount the Box
Use lag screws or bolts through the extended back piece into the tree. Don't use nails — they work loose over time. Mount 15–30 feet high facing east or south.
Properly mounted squirrel house on a mature tree trunk
Squirrel Nest Box Placement
Where you hang your squirrel house matters as much as how you build it. Poor placement means squirrels won't use it.
Height: Mount your squirrel box 15–30 feet off the ground. This mimics natural cavity heights and keeps the box away from ground predators. If you can't go that high, 12 feet is the minimum.
Tree selection: Choose a mature hardwood tree with a trunk at least 10 inches in diameter. Oak, hickory, maple, and walnut are ideal. Avoid dead trees that could fall.
Direction: Face the entrance hole east or south. This provides morning sun for warmth and keeps the entrance away from prevailing winter winds.
Mounting method: Use lag screws or bolts through the extended back piece into the tree. Don't use nails — they work loose over time.
Avoid These Locations
- Near bird feeders — too much competition and stress
- On thin branches — won't support the box weight
- In direct afternoon sun — overheating in summer
- Near busy pathways or doors
- Where cats can access nearby branches
If you have the space, install 2–3 boxes on different trees. Squirrels are territorial but may use multiple boxes seasonally. More boxes mean more opportunities for females to raise litters.
What Direction Should a Squirrel House Face?
Face the entrance hole east or south. This provides morning sun for warmth, protects against prevailing winter winds from the north and west, avoids the hot afternoon sun from the west, and keeps the entrance drier during rain storms that typically approach from the west. If you're unsure about wind patterns in your area, east is always a safe choice.
Best Time to Install a Squirrel House
| Season | Why It Works |
|---|---|
| Fall (September–November) | Squirrels actively seeking winter shelter — best timing |
| Late winter (February) | Before spring breeding season begins |
| Early spring (March) | Females looking for nesting sites for spring litter |
Avoid installing in summer when squirrels are already settled in existing nests. The best strategy: install in early fall. Squirrels will have time to discover the box and may move in before winter.
How to Attract Squirrels
Building a squirrel house is step one. Here's how to make your yard irresistible:
Oak, hickory, walnut, hazelnut, and beech trees. Acorns are a squirrel's number one food source. Even seedlings planted now will benefit future generations of squirrels on your property.
A shallow bird bath or ground-level water dish attracts squirrels especially in summer. Keep it clean and filled. Squirrels need water year-round, not just in hot weather.
Unsalted peanuts in the shell, sunflower seeds, corn cobs, walnuts and pecans. Place feeders near but not on the tree with your squirrel box so they discover both.
Don't over-clean your yard. Squirrels use leaves, bark strips, and twigs for nest bedding. Leave some leaf litter and fallen branches for them to gather freely.
Be patient. Squirrels may take weeks or months to discover and trust a new nesting box. Once one squirrel moves in, others will follow. Most boxes are occupied within the first year.
Squirrel House vs Squirrel Feeder
| Feature | Squirrel House | Squirrel Feeder |
|---|---|---|
| Purpose | Nesting and shelter | Food source |
| Maintenance | Annual cleaning | Regular refilling |
| Wildlife benefit | Raises survival rates | Supplemental nutrition |
| Year-round use | Yes | Yes, more critical in winter |
| Attracts squirrels faster | No | Yes |
| Long-term impact | High — supports breeding | Medium — supports health |
The best approach: use both. A squirrel feeder brings squirrels to your yard quickly. A squirrel house gives them a reason to stay and raise families. Place the feeder within sight of the nesting box so squirrels discover both at once.
Do Squirrel Houses Need a Predator Guard?
Unlike bird houses, squirrel boxes typically don't need predator guards. The 3-inch entrance keeps raccoons out, height deters ground predators, and no perch means predators have nothing to grip. However if snakes are common in your area, consider mounting the box on a metal pole with a cone baffle. Snakes can climb trees easily but struggle with metal poles and baffles.
Common Mistakes to Avoid
Too small and squirrels can't enter. Too large and raccoons can reach inside. Stick with exactly 3 inches for gray squirrels — this has been the proven standard for decades.
Pressure-treated wood contains chemicals that harm wildlife. Always use untreated pine, cedar, or cypress — no exceptions, even if treated lumber is all you have on hand.
A box mounted 6–8 feet up is easy for predators to reach. Go at least 12 feet minimum. 15–30 feet is ideal and dramatically improves occupancy rates.
Perches help predators, not squirrels. Squirrels grip the entrance hole edge easily with their claws. Never add a perch below the entrance hole on any wildlife box.
An entrance facing prevailing winter winds lets cold air and precipitation blow directly inside. Face east or south — this single decision dramatically affects winter occupancy.
Old nesting material harbors parasites. Clean out boxes once a year in late fall after breeding season ends. This takes 10 minutes and extends the life of the box for years.
Ready-Made Squirrel Houses & Feeders
Don't have time to build one? These are the squirrel nesting boxes and feeders wildlife enthusiasts actually use — shipped right to your door.
Pre-built cedar squirrel house with 3-inch entrance hole. Ready to mount — no tools required. Perfect if you want to skip the build and get straight to the wildlife.
Shop on Amazon →The best-selling squirrel feeder style — a miniature wooden picnic table that holds corn cobs and peanuts. Place near your nesting box and squirrels will discover both immediately.
Shop on Amazon →As an Amazon Associate, Private Lands Wildlife earns from qualifying purchases at no extra cost to you. Your purchase helps support our conservation work.
Squirrel House — Frequently Asked Questions
The Complete Squirrel Guide
Types of squirrels, what they eat, do they hibernate, baby squirrels, black squirrels, squirrel feeders — all in one complete guide from our 30-acre Michigan wildlife habitat.
Visit the Complete Squirrel Guide →
The Whispering Woods: The Hidden Door
Love sharing nature with your children? The Whispering Woods takes kids on a magical adventure where they learn about wildlife habitat through an enchanted forest. Willow the duck and his woodland friends — including a very busy squirrel — teach children about the natural world. Perfect for ages 6–12.
A 30-minute project that benefits squirrels for a decade. More wildlife guides from our Michigan habitat below.
Browse All Wildlife Guides →Building more than one box? A squirrel house is a great start, but the same cavity crisis that squirrels face hits birds, bees, and ducks too — and each needs its own exact dimensions. We've since added free printable plans for a bluebird house, a mason bee house, and a wood duck box, or browse them all in our complete guide to nest boxes.