Seal up the roof, put in some planters, pick some hardy plants, and you’ve got a living roof. That’s right — plants on the roof.
It’s a great concept, but it’s not exactly cheap and easy to maintain. For one thing, you’ll need a structural evaluation to assess how much load the building can take. Then you make decisions from there.
The National Association of Home Builders, in an evaluation of the roofs, determined that they do have thermal resistance and insulation properties. But you can’t just plant it and forget it — it needs constant maintenance, just like a garden. And whatever you do, don’t try to grow an oak tree up there.