Green Shed Roof Drainage

Pour a layer of gravel into the frame 2 3cm deep.

Green shed roof drainage. The rock aggregate should also have a suitable ph and be low in soluble salts to ensure plant growth is not adversely affected. 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 slope of a green shed roof needs to be a balance between being too steep or too shallow. Cut a piece of weed matting large enough to cover the roof and the inside of the frame.

Step 2 waterproof the shed. Having proper drainage on a green roof is a critical aspect of the system. It buffers water and allows excess water to drain away. During a dry period the water stored can be reabsorbed by the vegetation layer above.

Whereas too steep means that the growing medium slides down the roof. The drainage also contributes to good aeration of the plant roots. Step 4 build a retaining frame. This improves the drainage of the green roof which helps reduce soil erosion and aerate plants.

The clay and silt content of materials used in a rock aggregate drainage layer should be 10 per cent by mass. Make sure that the shed roof is fully waterproof. Green roof solutions offers many different drainage layer options depending on system goals regarding water retention. Green roofs are made up of several layers typically a waterproof root barrier layer to protect the roof a drainage layer water retention mat then the growing medium and vegetation.

A shallow roof pitch wont allow water to drain away. Older green roofs often used a permeable layer of rock aggregate such as scoria or gravel for drainage. When saturated these layers can weigh in at more than 100kg per square metre or 20lbs per square foot. Green roofs can range from roof gardens with raised beds and pots to rolled out green carpets to shed roofs containing planting cells that are filled with soil or compost and planted up with low growing perennials and grasses.

Make sure that the roof has a pitch that will enable drainage. The drainage layer has an important role to play in the total system structure of a green roof. Lay it over the gravel and attach to the frame using tacks. This roof was towards the shallow end of the spectrum and could perhaps have been a bit steeper.

If the pitch is more than 20 degrees from horizontal you will need to take precautions so the soil in your garden does not slip.