Today I wanna write about a topic, that made me think a lot in the past: The best size for rolling benches.

Rolling benches might look like a trivial topic for you. But deciding the width of rolling benches is a really crucial consideration when designing an indoor or greenhouse cannabis grow facility. The size of rolling benches in your facility have a big impact on how efficient your floor space is used and how easily plants can be accessed by gardeners for defoliation and other care keeping tasks. All this will contribute to the production cost of your cannabis products and should be well thought.

Technical aspects of rolling benches, that dictate rolling bench designs

Recently I had a talk with Greenfox, a leading horticulture company in Switzerland, which installs rolling benches in many CBD and medical cannabis facilities. Greenfox has much experience in technical solutions in the greenhouse and indoor grow sector and have great knowledge regarding technical aspects of rolling benches.

When I was designing my first indoor grow facility, I was keen on getting rolling benches, which are not wider than 1,20m or 4 feet. But when I reached out to Greenfox to get a quote, I got a fast feedback: They would recommend wider rolling benches because of better usage of floor space and lighting. I mean, I love great efficiency, but back then I was more thinking about work ergonomic aspects. I thought, with 1,2m or 4 feet wide tables, workers just have to reach plants 60 centimeters or 2 feet deep in the canopy. Even really small people with short arms can defoliate this way easily.

Ergonomic requirements vs. technical requirements of rolling benches

Unfortunately, not only work ergonomics make up the requirements for rolling benches, but also gravity and structural stability. So it turned out, that rolling benches with a width of just 1,20m or 4 feet can just be moved by 12,5cm on every side. This means, if we have two rolling benches side by side and move them both in a manner, that we get an aisle between them both, we just get 25cm of aisle width. This is way too less for workers being able to go through these two rolling benches to do defoliation or other plant keeping work.

For safety reasons, it’s not possible for conventional rolling benches to move them even more sidewards. Because then, the table can either turn over the edge and fall down or the structural stability would suffer. So to get an aisle width of about 75cm, which is a recommended distance to work between two rolling benches, we would need 50cm of “dead floor space” between each rolling benches. So however the 1,20m wide rolling benches are moved, there will be always at least 50cm of “dead space” between the two tables. Dead space, where you cannot place plants to make efficient use of your rent or light energy.

Fortunately, with wider rolling benches you can partially avoid this problem. With 2m / 6 feet wide tables you can move each table by 35cm each side – this makes up for 70cm aisles without having any dead space between the rolling benches. But with 2m wide tables it gets really hard, especially for small people, to reach the plants located at the center of each table. One has to stretch his or her arms 1 meter or 3 feet to reach these plants. So I would think about a compromise between 1,2m / 4ft and 2m / 6ft tables.

I think, 1,6m / 5 feet wide tables would make the deal. Because in this setup you just have 25 centimeters or 10 inches of dead, unused space between each table to get 75cm wide aisles. And workers just have to reach plants 80cm deep, measured from the edge of the table. Just keep in mind: 2m or 6 feet wide rolling benches are best practice for ornamental flower or smaller herb greenhouses. But in these cases, workers don’t have to grab into the canopy, but can reach all plants from above, as these flowers and plants are way lower in height than cannabis plants.

I just made some CAD Drawings, to show you the differences between 1,6m and 1,2m wide rolling benches.

It’s easy to see, that with the 1,6m wide rolling benches you use your valuable grow space way much better than with 1,2 wide rolling benches. I calculated a 16% better usage of floor space with 1,6m wide rolling benches. Especially when growing indoor, this makes a huge difference as floor space is way much more expensive than outdoors or in greenhouses. Just think of all the lights.

Fixed aisles for better aeration

When aiming for like 75cm wide aisles between the rolling benches when moved to the most outside positions, we still have these 25 centimeters of dead space between the 1,6m / 5ft wide rolling benches. What seems like heavily inefficient at first glance, turns out to be a big advantage in huge grow areas. Because all these gaps are useful for homogenous aeration and makes for better micro climates in the grow area. Also does it reveal all side branches of the plants positioned at the sides of each table to the top mounted light sources – so we will have more higher grade buds at the point of harvest.

Another advantage of the fixed way width for the 1,6m rolling benches: You don’t have to move all rolling benches in your room to the side, to get an aisle somewhere in the middle of the room. For this we have this 25cm of aisle width, which is exactly the same as the moving distance to each side of the rolling benches.

To conclude the rolling benches issue:

In the end, you’re free to decide which table width fits best for your very own grow project. Now you know some thoughts you can go though when planning and designing your own facility and can weigh up according to your personal needs, if you go with bigger dead spaces, wider tables or narrow aisle widths.

Don’t forget to reach out to info@research-gardens.com, whenever you’re in need of some help or consultancy for your grow project. Our team of well experienced horticulture engineers is here to help you out!