How to Build Under-the-Stairs Storage: Complete DIY Guide (Save $2,500)

The 47 Square Feet of Wasted Space Costing You Money

My client Rachel paid a custom carpenter $3,200 to build storage under her stairs. The project took three weeks and delivered exactly what a weekend DIY project could have accomplished for $650 in materials. She didn’t know any better—most homeowners assume built-in storage requires professional carpentry skills.

Meanwhile, my neighbor converted his under-stairs disaster area into a organized storage system for $580 over one weekend. He gained 38 cubic feet of usable storage solving his seasonal decoration chaos while spending 83% less than professional installation.

I’ve designed and built twenty-nine under-stairs storage projects since 2016—from simple shelving systems to elaborate pull-out drawer units. I’ve transformed everything from tiny coat closets under basement stairs to massive storage walls beneath grand staircases. What I’ve learned: the skills required are basic carpentry, the materials are inexpensive and available everywhere, and the satisfaction of reclaiming wasted space is worth way more than the modest investment.

Let me show you exactly how to build under-stairs storage that looks custom-designed, functions perfectly for your needs, and costs a fraction of professional installation while taking just one focused weekend.

Why Under-Stairs Storage Fails (And How to Avoid It)

Most under-stairs spaces become dumping grounds because they lack organized systems. You toss something under there “temporarily” and six months later you’re excavating through chaos trying to find it. Proper storage systems prevent this entirely.

The three reasons under-stairs storage fails:

Poor access design: Deep spaces without pull-out capability become unreachable black holes. Anything more than 24 inches deep needs sliding drawers or pull-out shelves—fixed shelving in deep spaces creates unusable areas.

Wrong shelf spacing: Adjustable shelving sounds good but creates indecision paralysis and wasted space. Fixed shelves sized for your specific storage needs maximize every cubic inch while providing defined homes for categories.

Ignoring the angle: Stair slopes create awkward triangular spaces. Amateur designs fight the angle with rectangular shelves leaving massive wasted areas. Smart designs embrace the slope using custom-cut shelves that follow the staircase geometry.

I measure under-stairs spaces in three dimensions accounting for the slope. This reveals actual usable volume versus the optimistic calculations people make looking at floor space alone.

Measuring and Planning Your Under-Stairs Space

Grab your tape measure, notepad, and flashlight. This planning phase determines everything that follows.

Critical measurements needed:

Height at entry point: Measure floor to underside of stairs at the access opening. This determines your tallest shelf or door height. Most staircases provide 6-7 feet at the entry diminishing to 3 feet or less at the back.

Depth from entry to back wall: Measure from the finished face where your door will install to the wall under the upper stairs. Typical depths range from 4-8 feet depending on staircase design.

Width of available space: Measure the full width available for storage. Sometimes support posts or mechanicals limit usable width—account for these obstacles.

Height progression along depth: Measure height every 12 inches moving from front to back. Record these measurements—they determine shelf heights at various depths.

My neighbor’s space measured 58 inches wide, 82 inches deep, with heights progressing from 78 inches at entry to 24 inches at the back wall. These specific dimensions determined his entire design approach.

Sketch your space including:

• All measurements clearly labeled
• Location of existing support posts or beams
• Electrical outlets or switches to preserve
• HVAC vents requiring clearance
• Any plumbing or mechanicals to avoid

Inventory your storage needs:

What are you actually storing? Be specific. “Seasonal items” is too vague. “Four plastic bins of holiday decorations, two suitcases, vacuum cleaner, golf clubs, and tool box” gives you exact dimensions to plan around.

I make clients list everything with measurements. This reveals whether you need open shelving, enclosed cabinets, hanging space, or drawer systems. Your stuff determines the design—not Pinterest photos of spaces storing completely different items.

Design Approaches for Different Under-Stairs Configurations

Your staircase location and configuration determines which design approach works best.

Open shelving system (simplest, lowest cost):

Best for: Basement stairs, utility areas, spaces where appearance matters less than function Cost: $180-400 in materials Time: 4-8 hours construction Skill level: Beginner with basic tools

This approach uses simple shelf standards and brackets following the stair angle. Paint everything the same color as walls and it looks intentionally designed rather than thrown together.

Cabinet with doors (most popular):

Best for: Living spaces where contents should remain hidden Cost: $450-850 in materials
Time: 12-20 hours construction Skill level: Intermediate carpentry

Build a simple frame, add shelving inside, then install a door concealing everything. This was Rachel’s carpenter’s approach—except he charged $3,200 for work you can DIY with careful planning.

Pull-out drawer system (most functional):

Best for: Deep spaces over 4 feet, frequently accessed items Cost: $650-1,200 in materials Time: 16-24 hours construction Skill level: Advanced intermediate

Individual sliding drawers maximize deep space accessibility. Each drawer pulls completely out providing easy access to contents. More complex but dramatically improves usability in deep under-stairs areas.

Hybrid approach (what I recommend):

Best for: Most under-stairs spaces Cost: $520-750 in materials Time: 12-18 hours construction
Skill level: Intermediate

Combine approaches—shelving for frequently accessed items near the entry, pull-out drawer for deep storage, enclosed cabinet for unsightly items. This maximizes flexibility while managing cost and complexity.

My neighbor used the hybrid approach: three fixed shelves in the tall entry area, two large pull-out drawers for the middle section, and open shelving in the narrow back section. Perfect balance of function and effort.

Materials and Tools You’ll Need

Essential materials for basic system (cabinet with shelves):

• Framing lumber (2×4): 6-8 boards at $6-9 each
• Plywood (¾-inch): 2-3 sheets at $50-75 each
• Shelf standards and brackets: $40-80
• Piano hinge or door hinges: $25-45
• Door handle/latch: $15-30
• Wood screws (various sizes): $25-40
• Wood glue: $8-12
• Sandpaper and supplies: $15-25
• Paint or stain: $30-50
• Total materials: $450-650

Tools required:

• Circular saw or table saw (cutting plywood and lumber)
• Drill/driver with bits
• Level (4-foot minimum)
• Tape measure
• Square (combination or speed square)
• Clamps (4-6 various sizes)
• Safety equipment (glasses, hearing protection, dust mask)

Don’t own a table saw? Home Depot and Lowe’s cut plywood for free or minimal charge. Bring your measurements and cut list—they’ll do the straight cuts saving you tool investment and improving accuracy.

Upgrading to pull-out drawer system adds:

• Drawer slides (heavy-duty, full extension): $35-65 per pair
• Additional plywood for drawer boxes: $50-100
• Drawer fronts or materials: $40-80
• Additional cost: $200-400

Step 1: Preparing the Space and Building the Frame

Clear everything out completely. This seems obvious but many people try working around existing junk—you’ll regret it. Empty the entire space, clean thoroughly, and start fresh.

Check for issues requiring attention:

• Water stains indicating leaks (fix before building)
• Electrical that needs relocating
• Uneven flooring requiring leveling
• Missing insulation if exterior wall

My client discovered a slow water leak from upstairs bathroom during demo. Fixing it cost $340 but prevented thousands in future damage to the new storage system.

Frame construction sequence:

Build base frame: Construct a level base frame from 2×4 lumber anchored to the floor. Use pressure-treated lumber if concrete floor or potential moisture exists. This base supports everything else.

Level is critical—an unlevel base causes doors that won’t close properly and drawers that roll open by themselves. Use shims under the base frame achieving perfect level before anchoring permanently.

Install vertical supports: Position 2×4 vertical studs at corners and every 24-32 inches along the opening width. These create the structure supporting shelves and doors.

Attach vertical studs to stair stringers above if accessible for maximum stability. If you can’t access stringers, attach to floor base frame and create a top frame connecting vertical studs.

Add cross-bracing: Install horizontal 2×4s between vertical studs creating attachment points for shelves. Position these at planned shelf heights plus top and bottom.

I build the frame overbuilt rather than minimal—the cost difference is maybe $30 but the stability difference is enormous. Use structural screws (GRK or similar) rather than standard deck screws for connections lasting decades.

Step 2: Installing Shelving Systems

Your shelf approach depends on whether you’re doing fixed or adjustable, and how you’re handling the stair angle.

Fixed shelving (my recommendation):

Cut plywood shelves to exact dimensions fitting between vertical supports. The back edge follows the stair slope—this requires angle cuts matching the stair pitch.

Calculating the angle: Use a digital angle finder ($15-25) measuring the stair angle directly. Transfer this angle to your saw for cutting shelf backs. Most stairs run 30-38 degrees—verify rather than guess.

Shelf support methods:

Cleats: Attach 1×2 or 2×2 strips to vertical supports creating ledges. Shelves rest on these cleats. Simple, strong, and allows easy shelf removal if needed.

Pocket screws: Attach shelves directly to vertical supports using pocket hole screws. Creates clean look without visible fasteners but makes shelf removal difficult.

Adjustable standards: Install shelf standards on vertical supports allowing height adjustability. More flexibility but less stable than fixed installation.

I use cleats for most projects—they’re strong, simple, and allow seasonal reconfiguration if storage needs change.

Shelf spacing strategy:

Don’t space shelves evenly. Design spacing around your actual items. If you’re storing plastic storage bins measuring 16 inches tall, space shelves 17 inches apart—not 15 inches (too tight) or 20 inches (wasted space).

Measure your storage items and design shelves with ½-1 inch clearance. This maximizes storage density while maintaining accessibility.

Step 3: Building and Installing Doors

Doors transform under-stairs storage from exposed shelving to integrated home feature. They also keep dust off stored items and hide visual clutter.

Door size considerations:

Full-height single door: Works for openings up to 36 inches wide. Beyond that, doors become heavy and awkward requiring heavy-duty hinges.

Double doors: Best for openings 36-72 inches wide. Creates elegant look while keeping individual door panels manageable size.

Partial height with open top: Install doors covering lower 4-5 feet with open shelving above. This provides concealed storage where needed while maintaining easy access to frequently used items.

My neighbor installed double doors covering the lower 60 inches with three open shelves above. This gave him hidden storage for seldom-used items while keeping everyday items accessible without opening doors.

Door construction options:

Frame-and-panel: Most professional-looking but requires advanced carpentry skills. Build a frame from 1×3 or 1×4, insert panel (plywood or MDF).

Flat panel with trim: Simpler approach I use most often. Cut ¾-inch plywood to size, add decorative trim creating raised panel appearance. Looks custom at fraction of complexity.

Pre-made doors: Purchase hollow-core interior doors cut to size. Cheapest and fastest but limited sizing options.

IKEA cabinet doors: Pre-finished doors in standard sizes. More expensive than DIY but perfect finish and hardware included.

I built frame-and-panel doors for my own home spending $180 on materials and 8 hours construction time. They look incredible but honestly, the flat panel with trim approach delivers 85% of the appearance at 40% of the effort.

Hinge installation critical details:

Use 3-inch hinges (not smaller) for stability. Install three hinges on doors over 60 inches tall, two hinges on shorter doors.

Piano hinges alternative: Continuous piano hinges running the full door height provide superior stability for large or heavy doors. Cost $25-45 but worth it for doors over 48 inches.

Install hinges so doors open 180 degrees if space allows. This prevents doors blocking access during use—surprisingly important for frequently accessed storage.

Step 4: Pull-Out Drawer Construction

Pull-out drawers dramatically improve deep space accessibility but add construction complexity and cost. Only necessary for spaces deeper than 48 inches where fixed shelves create unreachable areas.

Drawer slide selection matters enormously:

Cheap slides ($15-20 per pair): Rated 75 pounds, extend 75% of depth, fail within 2-3 years under regular use

Quality slides ($35-50 per pair): Rated 100-150 pounds, full extension, soft-close, last indefinitely

Ultra-heavy slides ($60-100 per pair): Rated 200+ pounds, full extension, smooth operation with heavy loads

I use Blum Tandem or similar quality slides ($40-55 per pair). They cost triple cheap alternatives but the operational smoothness and longevity justify the investment. Cheap slides frustrate users daily—that annoyance accumulates over years.

Drawer box construction:

Build simple boxes from ½-inch plywood with ¾-inch plywood bottoms. Use pocket screws, wood glue, and brad nails creating strong joints.

Sizing drawers properly:

Drawer width equals opening width minus 2 inches (1 inch per side for slide mounting).

Drawer depth equals slide extension length minus 1 inch.

Drawer height depends on stored items but 8-12 inches works for most applications.

Installation sequence:

Mount drawer slides to cabinet sides first ensuring they’re level and parallel. Install mating slides on drawer boxes. Test fit before final installation—adjustments are much easier before everything is screwed down permanently.

Add drawer fronts after installation allowing adjustment for perfect gaps and alignment. This two-piece approach (drawer box plus applied front) simplifies construction while delivering professional results.

Step 5: Finishing Touches That Elevate the Project

The difference between “homemade” and “custom carpentry” appearance lies entirely in finishing quality.

Fill and sand everything:

Use wood filler on screw holes, gaps, and imperfections. Sand smooth after drying. This takes 2-3 hours but transforms appearance dramatically.

I use Bondo for large gaps and holes—it’s harder and sands smoother than standard wood filler. For small imperfections, DAP Plastic Wood works fine.

Paint or stain properly:

Prime everything before painting. One coat of primer plus two coats of paint creates durable, professional finish. Don’t skip primer—it’s the foundation of everything.

For stain, use pre-stain conditioner on softwoods preventing blotchy appearance. Apply stain evenly, wipe off excess, then seal with polyurethane.

Interior treatment matters:

Paint interiors white or light colors improving visibility of stored items. Dark interiors make finding things difficult requiring flashlight even with front lighting.

Add LED strip lighting ($15-30) inside for automatic illumination when doors open. This simple upgrade transforms functionality especially for deep spaces.

Organizational accessories:

• Hooks on door backs for hanging items
• Small bins or baskets organizing loose items
• Labels identifying shelf contents
• Shelf liner preventing items from sliding

These small additions maximize functionality while keeping total project cost reasonable.

Cost Comparison: DIY vs. Professional Installation

DIY complete under-stairs storage:

• Materials (hybrid system): $520-750
• Tools (if needed): $150-300
• Time investment: 12-18 hours over one weekend
• Total DIY cost: $670-1,050

Professional custom carpenter:

• Labor (typically): $2,000-3,500
• Materials (marked up): $600-900
• Project timeline: 2-4 weeks
• Total professional cost: $2,600-4,400

Savings: $1,930-3,350

Rachel’s $3,200 installation could have been DIY’d for approximately $680 including a few new tools she’d use for future projects. That’s $2,520 saved for one focused weekend of work.

Common Mistakes That Ruin Under-Stairs Projects

Mistake 1: Not accounting for door swing

Doors need clearance to open. Measure your space considering furniture, walls, and traffic patterns. I’ve seen beautiful storage systems with doors that can’t open past 90 degrees because a couch is too close.

Mistake 2: Building first, measuring storage items second

This creates shelves that don’t fit your actual stuff. I watched someone build 14-inch shelves for 16-inch storage bins. Measure your items first, design around them second.

Mistake 3: Ignoring structural elements

Cutting into stair stringers or support posts creates dangerous structural problems. If you encounter structural components, work around them—never remove or cut them without engineering assessment.

Mistake 4: Cheap hardware on heavy doors

A 48-inch tall door made from ¾-inch plywood weighs 35-45 pounds. Cheap hinges sag within months requiring constant adjustment. Spend $40 on quality hinges preventing years of frustration.

Mistake 5: Perfect plans with poor execution

Take your time on cuts and assembly. Rushing creates gaps, misalignments, and sloppy appearance that no amount of paint can hide. Careful, patient work produces professional results regardless of skill level.

Your Weekend Build Timeline

Saturday morning (4-5 hours):

• Final space prep and cleaning
• Build base frame and vertical supports
• Install cross-bracing and structure
• Begin shelf cutting and installation

Saturday afternoon (3-4 hours):

• Complete shelf installation
• Build drawer boxes if applicable
• Begin door construction

Sunday morning (3-4 hours):

• Complete door construction
• Install hinges and hardware
• Mount doors and test operation

Sunday afternoon (2-3 hours):

• Fill imperfections and touch-up
• Install drawer slides and drawers
• Add accessories and organization
• Load storage items and enjoy

This timeline assumes moderate pace with lunch breaks and some problem-solving time. Experienced DIYers might finish faster, beginners might need an extra few hours—plan accordingly.

Making the Most of Your New Storage Space

You’ve built beautiful storage—now use it effectively.

Organization by access frequency:

Front shelves and top drawers: items used monthly or more Middle sections: seasonal items used 2-4 times yearly
Back areas: long-term storage accessed annually

Category grouping:

Store related items together even if different sizes. All holiday decorations in one area, all sporting equipment together, all tools in one location.

Labeling prevents chaos:

Label shelves or bins clearly. Six months from now you won’t remember where you stored the Halloween decorations without labels.

Annual audit:

Once yearly, pull everything out and reassess. Donate items not used in two years. Reorganize based on actual usage patterns rather than initial assumptions.

Ready to reclaim that wasted under-stairs space while saving $2,000+ on professional installation? The difference between amateur storage chaos and custom-looking built-ins lies in careful planning, patient construction, and understanding that skills matter less than following a proven system step-by-step.

What’s your under-stairs configuration like—open to living space, basement utility area, or something else? Share your measurements in the comments and I’ll suggest the best approach for your specific situation!