How to Build a Rooftop Garden

Rooftop gardens are all the rage both as a stylish feature and as an eco-friendly change to promote clean air and healthy bee populations.

A rooftop garden transforms your outdoor space, but the transformation means your design requires more work than a simple weekend project.

We’ll show you everything you need to build a roof garden the right way.

1. Check with Your City or Homeowner’s Association

Before setting your heart on a design, visit your city offices or homeowner’s association to learn about local ordinances and rules. You’re not only planting a garden but also modifying a structure. 

Cities may ban or severely restrict rooftop gardens, so check here first before paying for an assessment.

2. Get an Assessment

You love the idea, but is it achievable? Only a contractor or architect like ECO Roof & Solar will know for sure.

An assessment tells you how much weight your roof can take and directly impacts the design of your garden. Some buildings may require modification before they can handle the extra pressure.

Remember, your roof needs to support not only the weight of your garden as well as you on it.

Access may also be an issue. A rooftop garden loses its magic if you risk injury every time you access it.

3. Design Requirements

A thriving roof garden requires more than a spread of soil and some plants. It gets heavy, which is why a full impact assessment is the foundation of this project.

Because you’re not planting in a natural space, you’ll need several more layers to help your plants take root. These layers include:

  • Insulation
  • Pond liners
  • Root membrane
  • Gravel
  • Moisture
  • Blanket
  • Wood chips
  • Compost
  • Topsoil

These layers provide somewhere for the plants to sit, moisture, and drainage all while protecting the structure of the building.

Your goal is to provide everything you need without adding too much extra weight.

To minimize weight, consider using lightweight containers like foam or fiberglass. You might also limit yourself to lightweight potting soil, which is far lighter than garden dirt.

When adding gravel, consider using styrofoam peanuts rather than actual gravel.

Additionally, you’ll need added windbreaks. Rooftop gardens are more exposed than a traditional garden. Windbreaks need careful design because you don’t want to eliminate the wind and you want to avoid seeing the breaks knocked over at all costs.

4. Irrigation

How will you water your garden? Rainwater alone won’t provide cover most of the year.

Because lugging buckets of water up to your roof is both impractical and dangerous, you’ll want either an automatic irrigation system or a water storage system built into your roof.

Irrigation systems are inexpensive compared to the cost of the garden generally. Buy them on eBay or at a garden center for under $50.

Build Your Rooftop Garden Today

A rooftop garden brings life to your building, but they do require careful consideration.

With excellent planning, you’ll find that your new garden meets all your expectations and makes your little corner of the world a place where everyone can breathe easier. 

Looking for more ways to go green? Visit our blog for eco-friendly ideas for your home and business.