Reimagining the LEGO Tree House: 20 Inspiring Alternative Builds

From its lush canopy of leaves to its sturdy wooden beams, the LEGO Ideas 21318-1 Tree House set is a masterclass in organic architecture. But what if you could take those very same bricks and transform them into something entirely new? Thanks to the vibrant My Own Creation (MOC) community on Rebrickable, you can. Using only the pieces included in 21318-1, designers have crafted everything from rustic mills to medieval streets, each breathing fresh life into the set’s unique palette of bright greens, autumnal oranges, and rich browns .

These alternate builds showcase not only the versatility of the parts inventory—but also the boundless creativity of LEGO builders around the world. Imagine your Tree House set morphing into a cozy lakeside retreat, a windswept windmill perched on a hill, or even a mysterious Baba Yaga’s Hut straight out of Slavic folklore. Whether you’re drawn to medieval blacksmith shops or tranquil bonsai trees, there’s an MOC here to spark your next build session. And because each design reuses the original elements, you can switch between your favourite creations without ever needing extra bricks.

Below, explore 20 standout alternative builds. Click on any to dive into step-by-step instructions, then gather your Tree House parts and get building!

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Alternative Builds

Arcadian Hut

Designer: nobsta
Get the instructions: Rebrickable – Arcadian Hut

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Lake House

Designer: Gr33tje13
Get the instructions: Rebrickable – Lake House

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Mill on the Hill

Designer: nobsta
Get the instructions: Rebrickable – Mill on the Hill

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21318 MOC – Watermill

Designer: torsten_o
Get the instructions: Rebrickable – 21318 MOC – Watermill

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Family Cabin

Designer: Gr33tje13
Get the instructions: Rebrickable – Family Cabin

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Forest Lookout

Designer: Gr33tje13
Get the instructions: Rebrickable – Forest Lookout

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Forest Cabin

Designer: Gr33tje13
Get the instructions: Rebrickable – Forest Cabin

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Bonsai Tree

Designer: Gr33tje13
Get the instructions: Rebrickable – Bonsai Tree

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21318 Modular Medieval House

Designer: gabizon
Get the instructions: Rebrickable – Modular Medieval House

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The Observatory

Designer: Gr33tje13
Get the instructions: Rebrickable – The Observatory

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Medieval Blacksmith

Designer: gabizon
Get the instructions: Rebrickable – Medieval Blacksmith

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21318-1 Lighthouse

Designer: emil_mu
Get the instructions: Rebrickable – 21318-1 Lighthouse

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Micro Tree House

Designer: pomx
Get the instructions: Rebrickable – Micro Tree House

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21318 Alternative Pack (5 MOCs)

Designer: gabizon
Get the instructions: Rebrickable – Alternative Pack

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Tree House Forest Bundle

Designer: Gr33tje13
Get the instructions: Rebrickable – Forest Bundle

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3-in-1 Alternative Build (3 MOCs)

Designer: gabizon
Get the instructions: Rebrickable – 3-in-1 Alternative Build

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Creek Hut

Designer: PL MOCs
Get the instructions: Rebrickable – Creek Hut

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Medieval Street

Designer: gabizon
Get the instructions: Rebrickable – Medieval Street

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Windmill

Designer: gabizon
Get the instructions: Rebrickable – Windmill

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Baba Yaga’s Hut

Designer: PL MOCs
Get the instructions: Rebrickable – Baba Yaga’s Hut

 

Click here for more alternative builds and Modifications for this Lego set