Insurance

Some people make a decision and immediately set out to execute it. They forget that before you put out a lot of money and time you always need a solid plan. Any construction project requires planning which may be extensive. If any step of that plan is ignored or not thought of it can cost the owner a lot of money to basically start over. If the green roof leaks it may have disastrous results.

One error is to consider a living roof as a short term project. Once you have properly installed a green roof you will have changed your environment. Anything that impacts your environment on a long term basis deserves some consideration. You will have to think about water management both runoff and retention. A green roof will make the building more energy efficient and allow better control of heat and cooling usage. You might consider a roof top solar system. An intensive green roof may allow a park like setting on the roof.

Don't ignore the load capacity of the roof structure. Whether this is a new construction project or a remodel you have to insure you have enough structural support to handle the additional weight of a green roof. Without a certified structural report you may be heading to serious trouble.

Don't think the roof will be self supporting. It won't. It requires maintenance. To have adequate maintenance whether it's an intensive or extensive roof requires access. Every step should be taken to insure anyone walking on the roof to provide maintenance should be safe. They can't be expected to wear a safety harness and hard hat to go up on the roof to maintain it.

Every living roof requires water and proper drainage. You can't ignore this fact. An extensive roof may require less water than an intensive roof but it still requires initial watering and in periods of low rainfall, some form of ancillary watering. In addition to insuring adequate watering you need to insure the water doesn't pool up and cause root rot. Roots don't like to sit in standing water for long periods of time. Water build up may also damage the various layers of the green roof and cause a roof leak into the building. A proper green roof will have a proper ratio of water retention and water runoff. This also affects the storm water runoff during the year. So the local climate needs to be a consideration in your plans.

Where you live physically is also a factor in how and what goes into your green roof design. Do you have long periods of sun or long periods of wind? Which way will the plants face? Will it get a lot of shade? Are there other tall trees surrounding the roof that may overshadow it? Lower profile plants may not get enough sunlight. Taller plants with a shallow root system may not survive a wind storm. All of these need to be considered during the planning process.