That exciting delivery has arrived—boxes of timber panels, bags of hardware, and an instruction manual that may or may not make sense. Assembling a flat-pack cubby house is achievable for most DIY-ers with basic skills, but it does require planning, patience, and the right approach. This guide shares professional tips to help you achieve a safe, sturdy result you'll be proud of.
Before You Start: Preparation is Everything
Read the Instructions Completely
Resist the temptation to dive straight in. Reading the entire instruction manual before touching a single component will save hours of frustration and potential mistakes. Pay attention to the sequence of steps—most cubby houses must be assembled in a specific order, and jumping ahead often means having to backtrack.
Note any steps that seem confusing while reading. You can often find clarification videos online from the manufacturer or other builders, and it's much easier to research before you're halfway through assembly with a helper holding a heavy panel.
Inventory Your Components
Unpack everything and check against the parts list before starting. Lay panels out in groups and count hardware items. This prevents the frustrating discovery mid-assembly that you're missing a crucial component. If anything is missing or damaged, contact the supplier immediately—most will ship replacement parts promptly.
âś“ Pre-Assembly Checklist
- Read all instructions thoroughly
- Check all parts against inventory list
- Inspect components for damage
- Gather all necessary tools
- Prepare the installation site
- Check weather forecast for assembly day
- Arrange helper(s) for heavy lifting
- Plan to keep children and pets away during assembly
Gather Your Tools
Most cubby house kits list required tools in the instructions. Common needs include:
- Power drill/driver: Essential for efficient screw driving. Ensure batteries are charged.
- Socket set or spanners: For bolt tightening
- Spirit level: Critical for ensuring your cubby is level
- Rubber mallet: For persuading tight-fitting joints without damage
- Tape measure: For checking dimensions and spacing
- Step ladder: For reaching roof assembly safely
- Safety glasses and gloves: Basic protection
Having the right tools on hand before you start prevents frustrating trips to the hardware store mid-project.
Site Preparation
Level the Ground
A level base is crucial for both safety and the structure's longevity. Use a long straight edge (a long spirit level or a straight board with a level on top) to check for high and low spots. Remove high points by scraping away soil. Fill low points with compactable material like crusher dust, not loose soil that will settle.
For timber cubbies, ensure the ground slopes slightly away from the structure to prevent water pooling against the base. A fall of about 1-2cm per metre is ideal.
Consider a Base Layer
Many professional installers recommend placing the cubby on a base of compacted crusher dust, pavers, or a timber sub-frame rather than directly on soil. This improves drainage, helps maintain level, and keeps timber components away from ground moisture. If using pavers, ensure they're level and provide solid support under all load-bearing points.
Assembly Tips by Cubby Type
Plastic Cubby Houses
Plastic cubbies are generally the easiest to assemble, often requiring just basic tools and an hour or two of time. Key tips include:
Don't overtighten: Plastic can crack if screws or bolts are overtightened. Tighten until snug, then stop.
Warm is better: Plastic is more flexible and easier to work with in warm conditions. If assembling on a cold day, let panels sit in the sun for a while first.
Align holes carefully: Forcing misaligned holes can crack plastic panels. If holes don't align, check you haven't mixed up similar-looking panels.
⚠️ Common Assembly Mistakes to Avoid
- Assembling panels in wrong order
- Not keeping children clear during assembly
- Overtightening fasteners (especially in plastic)
- Not checking level as you go
- Rushing and skipping steps
- Assembling alone when helpers are needed
Timber Cubby Houses
Wooden cubbies require more time and care. These tips will help achieve professional results:
Pre-drill screw holes: Even if not specified in instructions, pre-drilling pilot holes prevents timber splitting, especially near edges. Use a drill bit slightly smaller than your screw diameter.
Don't fully tighten immediately: When joining multiple panels, insert all bolts and screws first, leaving them slightly loose. This allows adjustment to ensure everything aligns properly. Once everything fits correctly, go back and tighten all fasteners.
Use temporary bracing: Large wall panels can be unwieldy. Use temporary braces (scrap timber screwed diagonally across frames) to hold walls plumb while you complete assembly. Remove braces once the structure is fully connected.
Check level constantly: Check level after each major step. A slight error compounds as you build upward. It's much easier to correct early than to fix once the roof is on.
Working Safely
Get Help When Needed
Some steps genuinely require two or more people. Trying to hold a heavy roof panel in place while driving screws is unsafe and produces poor results. Recruit a helper for at least the major structural steps—wall raising and roof installation particularly.
Keep Children Clear
We know the kids are excited about their new cubby, but assembly day is not the time for them to "help." Exposed screws, heavy panels, and power tools create genuine hazards. Keep children well away from the construction zone until assembly is complete and all tools are packed away.
Watch the Weather
Choose a day with good weather for assembly. Wind makes handling large panels dangerous, rain makes surfaces slippery and can damage timber before protective coatings are applied, and extreme heat leads to fatigue and mistakes. A mild, calm day is ideal.
Finishing Touches
Check Everything Twice
Before declaring the job complete, methodically check every fastener. Are all screws fully driven? Are all bolts tight? Do any panels have gaps that shouldn't be there? A complete check now prevents problems later.
Apply Protective Coatings
If your timber cubby comes unfinished or partially finished, apply protective stain or oil before exposing it to weather. Pay particular attention to end grain and any cut edges—these absorb moisture fastest. This step is much easier before the cubby is full of children and toys.
đź’ˇ Pro Tip: Document Your Build
Take photos throughout the assembly process. These are useful for troubleshooting if issues arise, handy for future maintenance reference, and make great memories of the day you built your kids' cubby. Plus, some manufacturer warranties require proof of correct installation.
Install Anchoring
Secure your cubby to the ground using appropriate anchoring for your soil type and the structure's specifications. This might be concrete footings, screw-in ground anchors, or stakes. Don't skip this step—an unanchored cubby can shift in use and become dangerous in strong winds.
Add Safety Surfacing
Complete the fall zone with appropriate impact-absorbing material before allowing play. Having soft-fall surfacing in place from day one establishes good habits and protects from that very first climb.
When to Call a Professional
There's no shame in recognising when a job is beyond your skills or available time. Consider professional installation if you're not confident with basic tools, if the cubby is large or complex, if the site requires significant ground preparation, or if you simply don't have the time to do it properly.
A poorly assembled cubby house is a safety hazard. If there's any doubt, the cost of professional installation is well worth the peace of mind.
After Assembly
Once your cubby is up, do a final safety walk-around. Check that there are no exposed screw points or sharp edges at child height. Ensure doors and shutters operate freely without pinch points. Test the stability by pushing firmly against the structure—there should be no significant movement.
Then stand back, take a photo, and enjoy the moment. You've built something that will provide years of joy and memories for your family.