Foundation Frame for Riga XL 9
Foundation Frame for Riga XL 9 Greenhouse
The Riga XL 9 Foundation Frame is the purpose-built ground installation solution for the Riga XL 9 greenhouse — one of the largest models in the Riga XL series. Buried in a trench and backfilled with soil, it securely anchors the greenhouse directly to the ground without requiring a concrete foundation, while also raising the greenhouse height for additional headroom and growing space.
*Free shipping only when purchased together with a Riga greenhouse. Ordered separately, an additional shipping charge applies.
Key Features
- Designed specifically for the Riga XL 9 greenhouse model
- Buried in-ground installation — no concrete required
- Backfilled with soil to securely anchor the greenhouse
- Raises the greenhouse height — adds headroom and growing space
- Purpose-built Riga accessory — engineered to fit the Riga XL 9 footprint exactly
Specifications
| Compatible Model | Riga XL 9 |
| Installation Method | Buried in trench, backfilled with soil |
| Foundation Required | No concrete — installs directly into ground |
| Benefit | Secures greenhouse to ground; adds height for headroom and growing space |
| SKU | RIGA-XL9-BASE |
| Price | $3,149 |
| Shipping | Free when purchased with a Riga greenhouse; additional charge when ordered separately |
How the Foundation Frame Works
- Dig a trench around the perimeter of your greenhouse site to the required depth
- Position the foundation frame in the trench at the correct level
- Backfill the trench with soil and compact to secure the frame
- Attach the Riga XL 9 greenhouse structure to the foundation frame
This method provides a secure, stable anchor without the cost or permanence of a concrete foundation. The raised frame height also gives you additional interior headroom and growing depth compared to a ground-level installation.
Complete Riga Foundation Frame Series
Riga foundation frames are model-specific — order the frame that matches your exact greenhouse model:
| Model | Foundation Frame | Price |
|---|---|---|
| Riga IIs | Riga IIs Foundation Frame | $824 |
| Riga IIIs | Riga IIIs Foundation Frame | $1,049 |
| Riga III | Riga III Foundation Frame | $1,299 |
| Riga IVs | Riga IVs Foundation Frame | $1,399 |
| Riga IV | Riga IV Foundation Frame | $1,499 |
| Riga V | Riga V Foundation Frame | $1,749 |
| Riga XL 5 | Riga XL 5 Foundation Frame | $2,099 |
| Riga XL 6 | Riga XL 6 Foundation Frame | $2,199 |
| Riga XL 9 | This frame | $3,149 |
If you are unsure which model you have, check your greenhouse documentation or contact us with your model number before ordering.
Frequently Asked Questions
What is the Riga XL 9 greenhouse?
The Riga XL 9 is one of the largest models in the Riga XL series — a premium German-engineered greenhouse with the distinctive "onion" arch profile, multi-wall polycarbonate glazing, and the structural performance the Riga series is known for. The XL series is the expandable line within the Riga lineup, with the number suffix indicating the length configuration.
Is the foundation frame required for the Riga XL 9?
A proper foundation is strongly recommended for structural integrity, stability, and warranty compliance. The foundation frame is the recommended solution for soil or lawn installations. If you are installing on an existing concrete pad, you may not need this frame — contact us to confirm the right foundation approach for your site.
Does the foundation frame add headroom inside the greenhouse?
Yes — because the frame raises the greenhouse above ground level, you gain additional interior height compared to a ground-level installation. For the Riga XL 9 — one of the largest greenhouse structures in the Riga lineup — this additional headroom further enhances the already generous interior space.
How deep does the trench need to be?
The required trench depth depends on your local frost line and soil conditions. Refer to your Riga XL 9 installation instructions or contact us for the recommended trench depth for your climate zone.
Can I install the foundation frame myself?
Yes — the installation process (dig trench, position frame, backfill, attach greenhouse) is designed for DIY completion. Given the large footprint of the Riga XL 9, having two or more people is strongly recommended for frame positioning and alignment. Refer to your Riga XL 9 installation instructions for specific guidance.
Why is free shipping only available when purchased with a greenhouse?
The foundation frame ships free when ordered together with a Riga XL 9 greenhouse because it can be included in the same freight shipment. When ordered separately, it ships as a standalone item and an additional shipping charge applies due to its size and weight.