A green roof installation can take anywhere from one week to several months depending on the size, logistics, design, weather, and access to the roof. Each building and client is different anf therefore there is no one size fits all for installations. However, an 800 SF green roof installation on a brownstone renovation project usually takes 2 to 3 weeks from start to finish if there is easy access.

Typically, a green roof is installed in the following order: a root barrier is installed above the waterproofing. Then a drainage layer that can be either be a drainage roll, drainage plates, or actual drainage aggregate. The next layer can be several things; filter fabric, capillary mat, or mineral wool, depending on the project and supplier, but regarless the type of material used here, this layer needs to divide and protect the drainge layer from the next layer which is the soil medium. Green roof soil medium is made from mostly expanded shale. This is medium is engineered to be lightweight, poros, and long lasting. It is mixed with anywhere from 30%-10% organic compost. Soil is brought to the roof in cubic foot bags by workers or can be elevated to roof by crane, or by soil blower truck. Cranes and trucks of this kind often require street permits. The soil medium is usually between 4”-6” deep. If irrigation is going to be used, then it is usally installed in this layer. Dripline irrigation is the most common system used for green roofs, but microdrip and sprinkler systems can also be installed. The irrigation is controlled by an automatic timer and programmed by the installer. The last layer, the plants, can come in the form of sedum mats, plant plugs (small rooted plants that are only 3”-5” deep), seeds, or larger perennials.