Green Roof Drainage Options

Three thicknesses of drainage plates are available to meet the drainage and water storage requirements of almost any green roof.

Green roof drainage options.

For flat or nearly flat roofs primary drains are located at the lowest point of the roof. A green roof may require a separately plumbed secondary drainage system also known as the overflow relief system. It buffers water and allows excess water to drain away. You should place the anchor elements directly above the drainage layer and filter fabric.

When you re thinking about what goes into a green roof the terminology can really get in the way. The design of the different drainage layers allows for a portion of the stormwater to be retained above where the water is allowed to flow freely off of the roof. The drainage layer has an important role to play in the total system structure of a green roof. J drain grs 400 rb is our most popular drain products under planted areas on greenroofs.

If stone ballast is being utilized around the drain the 84 option shown above. Grs drainage products include grs filter fabric grs drainage panels grs drainage layer composite cores and grs aggredrain. Green roof solutions can provide you with everything that you need for a successful green roof installation including. Technically speaking the term green roof applies to a roof upon which living plants have been planted and nurtured.

Zurn offers a variety of roof drain solutions suited for modular green roofs such as the z163 and the 84 options both shown below. Flow of water into them is promoted by positive drainage. They are pre assembled drain cores with root resistant filter fabric attached to top layer. Because green roof soil systems like rooflite s rooftop trees soil system are built up from the bottom it s easy to bury steel mesh concrete blocks lawn grid pavers or ballast stones to use as anchors for trunk tie downs or root ball strapping.

Green roof solutions offers many different drainage layer options depending on system goals regarding water retention. Depending on regional precipitation rates and the water retention goals for your specific project green roof solutions has a full range of products to meet your needs. Think the hanging gardens of babylon. 25mm 1 thickness is standard for thin extensive roofs 40mm 1 5 is recommended for enhanced water storage and drainage on thicker extensive roofs and semi intensive roofs and 60mm 2 5 is available for.

They are pre assembled drain cores with root resistant filter fabric attached to top layer. Oddly enough though this style of green roof isn t a cool roof. The drainage also contributes to good aeration of the plant roots. During a dry period the water stored can be reabsorbed by the vegetation layer above.