Treehouse Building Set - 21318
Ideas Tree House (21318)
Trusted by thousands of adult builders worldwide.
An iconic adult build designed for builders 16+.
Over 3,000 pieces. One unforgettable display.
✔ Ideas Set ✔ Adult Build (16+) ✔ Limited Availability
Why Is The Price Lower?
We work with limited inventory batches, overstock units, and promotional allocations. By reducing retail overhead and operating online-only, we're able to offer better pricing while maintaining full product quality and secure fulfillment.
Not a Toy — A Build Worth Displaying
The Ideas Tree House is created for adults who love thoughtful design, immersive building, and display-worthy results. Once completed, it becomes a centerpiece — not something you put back in the box.
Why Adult Builders Love It
🧠 Challenging & Rewarding
Over 3,000 pieces create a deeply engaging build that takes hours — not minutes.
🍃 Nature-Inspired Design
Organic textures, tree structure, and interchangeable seasonal leaves.
🏡 Display-Worthy Finish
Designed to look stunning on shelves, desks, or in your living space.
Packed With Thoughtful Details
- Three uniquely designed tree house sections
- Fully detailed interiors with furniture and accessories
- Removable roofs for easy viewing
- Hidden elements and playful surprises
- Interchangeable green & autumn-colored leaves
Genuine Ideas Construction Set
This is a genuine Ideas product — not a replica, not a clone. Every set is complete and carefully packaged to ensure a premium experience.
A Ideas Classic Loved Worldwide
Frequently praised by adult fans as one of the most iconic Ideas sets ever released.
1,200+ Adult Builders Ordered This Month
⚠ Limited Clearance Batch
Only 17 units remaining from this batch.
Once sold out, price returns to regular retail.
Buy With Confidence
Designed for builders 16+. Limited availability.
Shop With Confidence
We understand that some websites advertise unusually low prices but fail to deliver products. Your trust matters to us, and we operate with full transparency and accountability.
Our Commitment to You:
- ✔ Guaranteed Fulfillment: Every order is processed, packed, and shipped with tracking.
- ✔ Complete Set Assurance: If any piece is missing or damaged, we provide free replacement parts.
- ✔ 30-Day Protection: If your order has any issue, we offer replacement or refund support.
- ✔ Secure Payments: Encrypted checkout for full payment protection.
Need Assistance?
If you ever need help, simply contact our support team and we’ll respond promptly.
Dimensions
Measures over 14” (37cm) high, 10” (27cm) wide and 9” (24cm) deep.
Treehouse Building Set - 21318
- Secure PayPal Checkout
- Ships in Original Box
- Free Missing-Parts Replacement
- Checked Before Shipping
- Tracked Delivery
Shop With Confidence
Everything you need to know before placing your order.
Why do customers choose Wayfairusa?
- Detailed, display-worthy building sets for adult builders and collectors
- Fair prices without the usual retail markup
- Every set ships in its original box
- Free replacement for any missing pieces
- Secure checkout with PayPal and major cards
- Friendly email support from a real team
Why is this set priced lower than retail?
We work directly with the manufacturer and sell online only, so there are no wholesaler or retail-store markups to pay for. That lets us offer large, detailed building sets at a much friendlier price.
wayfairusa sets are compatible building sets. They are not official LEGO® products and wayfairusa is not affiliated with the LEGO Group.
Does it come with the original box?
Yes. Every set ships in its original manufacturer box, with the numbered bags and instruction booklet packed inside, so it's ready to build or give as a gift.
Are all parts included?
Yes. Each set is checked before it leaves our warehouse to make sure all pieces and the instructions are included.
What if a piece is missing?
It happens rarely, but if a piece is missing we'll send a replacement free of charge. Just email hello@wayfairusa.store with your order number, the bag number and a photo or the part number from the instructions.
How long does shipping take?
| Order processing | 1–3 business days |
| United States | 7–15 business days |
| Europe | 7–15 business days |
| Other countries | 10–20 business days |
You'll receive a tracking number by email as soon as your order ships.
My order is taking longer than expected. What can I do?
Because many of our sets are in high demand, some orders may take longer than the usual delivery time. Thank you for your patience. We'll get your set to you as quickly as we can and keep your tracking updated.
If you'd prefer not to wait, email hello@wayfairusa.store with your order number and we'll cancel your order and issue a full refund within 1–3 business days. Depending on your bank or PayPal, it may take a few extra days for the refund to appear in your account.
Is payment secure?
Yes. You can pay with PayPal or major credit and debit cards, as shown at checkout. All payments are processed through encrypted, secure payment gateways, and we never see or store your full card details.
What if my order arrives damaged?
Please email us within a few days of delivery with your order number and photos of the damage. We'll send replacement parts or arrange another solution for you.
Do you accept returns?
Yes. Contact us within 30 days of delivery and our team will help with a return, replacement or refund.
Is this set suitable for collectors?
Absolutely. Many of our customers are adult builders and collectors. Our ships, supercars, landmarks and display models look great on a shelf, desk or in a display case.
Email us at hello@wayfairusa.store. We're happy to help.