Credits to Steve Lloyd, one of our happy customers
“If you've recently purchased the Sungrow 32 greenhouse from Planta, you might have noticed something that needs to be added in their instructions: details about installing the tie-down anchor strap, especially on a 6x6 perimeter foundation.
Having gone through the installation process, I’d like to share some useful tips and tricks I picked up while completing the project solo.
Even if you're working with a helper, I believe the steps below will save you time and ensure a smooth installation.
Understanding the Structure
The Sungrow 32 greenhouse comprises ten rows of polycarbonate panels with steel ribs under each side.
There are 11 ribs in total, and there’s a corresponding tie-down strap for every rib.
If you have a smaller Sungrow model, the installation method will remain the same, with fewer ribs and straps.
Step 1: Preparing the Straps
Before starting the installation, I uncoiled each strap and laid it out on the greenhouse floor one at a time.
This step might seem simple, but keeping the straps organized from the beginning can make the installation smoother.
Here’s a quick trick: match the two ends of the strap where the bolts will go and temporarily fasten them together using adjustable locking pliers. This helps keep the straps straight and makes it easier when you're ready to install them.
Step 2: Finding the Center
Once the straps were laid out, I worked on identifying the center of each strap. Holding the two layers of steel strap together, I gently folded the center point to create a slight crease.
Be cautious here—don’t fold the strap too tightly. The idea is to form a bend that will mark the center without damaging the steel.
The center of the strap is important because it will sit on top of the ridge cap, ensuring even distribution of the strap’s hold-down strength across the ribs.
Step 3: Positioning and Securing the Straps
Since I was installing the straps solo, I found it helpful to tape them in place.
With a stepladder, I was able to reach all nine of the central ribs from inside my greenhouse (I have six windows cut out, making it easier to access these areas).
If you don’t have windows, you can still follow this step by working from the outside with a ladder.
The goal here is to keep the strap aligned with the steel ridge cap as you work. I used small pieces of Gorilla tape to secure the creased center of each strap to the ridge cap.
The tape ensures that the straps stay in place and don’t shift during the tightening process.
Step 4: Attaching the Straps to the Foundation
After all 11 straps were taped to the ridge cap and aligned properly, I moved on to threading the bottom anchor to both ends of each strap.
Planta's hardware includes M6x60 bolts, which I loosely fastened to allow for future tightening.
Once everything was loosely assembled, I began centering the lower part of the strap against each rib.
With the Gorilla tape still holding the ridge cap in place, I pressed firmly to keep everything snug.
I then marked the anchor strap with a felt-tip pen to show where it would need to be cut to fit flush against the bottom of the 6x6 perimeter foundation.
Using tin snips, I trimmed the anchor strap and pre-drilled the holes for the screws.
If your foundation has more than one layer of 6x6s, I suggest drilling the anchor holes farther apart to distribute the load over a larger surface area.
Step 5: Securing the Anchor Strap
With the holes drilled, it was time to secure the anchor strap to the foundation using galvanized screws.
I laid the strap against the polycarbonate panels, making sure it was perfectly aligned with the rib.
With one hand holding the strap in place, I used an impact driver to seat the upper screw into the pre-drilled hole.
You’ll notice that the strap might twist slightly during this process, but don’t worry—there’s still time to realign it before you install the second screw.
Once all the screws are in place, you’ll repeat the same steps for the remaining ribs.
Step 6: Tightening the Straps
At this point, all the straps should be securely attached to the greenhouse, but none of the bolts should be fully tightened yet.
I went down one side of the greenhouse and lightly tightened each hold-down bolt.
The goal here is to pull the straps snug against the polycarbonate without over-tightening, which could misalign the strap from the ridge cap.
For the final tightening step, I worked from side to side, tightening each strap a little at a time to ensure that all the bolts were evenly fastened.
The Finished Product
With all the straps tightened down, the Sungrow 32 greenhouse looked secure and sturdy.
The straps lay evenly on the ridge cap, providing strong hold-down power. For those who appreciate a clean, organized appearance like I do, you’ll be pleased to see how uniform the straps and bolts look when they’re properly aligned.”
We would like to thank Steve for this incredible contribution!
Ready to roll up your sleeves and strap down your Sungrow greenhouse? You can also use our BILT app and installation videos. Check them out!