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By Nicolas Ancion (ULg), David Volk (EBF), Ismaël Baraud (CSTB), Laurent Reynier (CSTB), Bernard de Gouvello (CSTB), Marcel Deravet (IFSB), Nicolas Brulard (Gally)


How can I find a producer?

Start by meeting farmers before building the greenhouse to make sure that the kind of greenhouse is interesting for them! Then make them participate to certain steps of the RTG design.

How can I involve a farmer in the project?

Considering all points of view is a complex and very important task. Involving the future RTG users is a key success factor for your project. The sooner they are in the loop, the better.
The use of this rooftop should be considered to save time and money in the design and construction of the work. Management and maintenance costs should be considered, as well as operating constraints.

Will the greenhouse be accepted by the inhabitants / residents / co-owners? How can I get them involved?

The project might not just need to be accepted, but welcome and expected. Several techniques can be used. You could organise personal meetings and then group meetings.

But for that, you need to clarify the expectations and fears of the different users and people impacted by the project. Urban greenhouse projects have been blocked and cancelled following complaints from residents.

Online tools can be used at each step if face-to-face is not possible. The first steps should be done before or at the beginning of the design of the greenhouse.

NB: Once the usage has been chosen collectively, greenhouse management and internal regulations might be needed (and co-created before).

This point is often forgotten but it is also crucial in such a project. These people can be reluctant at first and become real ambassadors of your project if you devote some of your time to them.

How much does it cost to build a greenhouse?

As said in the construction questions, a steel-framed greenhouse costs around 175 to 220 €/m². This cost can be multiplied by 3 to 15 depending on the modifications to be made to the building or the required production devices.

How can I build my business model around my project?

See Thematic Sheets, Strategic part.

How can I find a roof?

Tips: your network, the municipality, the GROOF network, Google earth, etc.
Are you sure you want a roof? Do you need an urban farm? An urban greenhouse or an RTG? Greenhouse-friendly rooftops are rare, so find them but also prepare a plan B! And walk around the city.

How can I convince investors and public authorities to fund the project and be part of it?

Your arguments need to be adapted to each prospect: know their needs and fears to reassure and convince them. Show them what your project can offer them (e.g. a green and innovative image for public authorities) Show how your project is different from the others.
Remember: you are not alone. The GROOF European project has already developed strong knowledge on this subject!

How can I find a partner?

Before finding a partner, it is very important to be very clear about why you are setting up this project.
So be clear about your skills and which tasks you wish to accomplish in this project.
Then ask yourself what complementary skills are needed for your project.
If you are very clear with these elements, then take time to talk about your project on every occasion. Professional events (conferences, masterclasses, etc.) as well as private events are opportunities to share about your project and hear about someone who could be the ideal partner. You can also create these situations by meeting the local public authorities, business owners or managers, stakeholders of urban farming, and so on.

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