Green Roof System Analysis

1243 Words5 Pages
Structural Layer:

The components of the structural layer consist of the roof deck (Snodgrass & Mclntyre,
2010); the protection layer to contain the roots and growing medium, while allowing water penetration; a drainage layer and retention layer (sometimes with built in water reservoirs); a root repellent filter layer (made up of filter mats to protect the growth media from moving); along with the waterproofing membrane (Peck, 2008).

(I) Roof Deck, waterproofing and insulation - The most important layer on a green roof is its decking, which can be concrete, wood, metal, plastic, gypsum or composite as it determines whether the structure is capable of taking the load of the green roof (Cantor,
2008). Installation of a green roof requires additional
…show more content…
The waterproofing membrane is the primary protective element of the slab and is typically below all the components of a green roof system (Weiler & Barth, 2009). There are three major roofing types for roofs – Built up membrane, single ply membrane and Fluid applied membrane (Osmundson, 1999). It is important that selection of waterproofing membrane is in accordance with specification of other components within the green roof system. Insulation – The roof is the primary location for heat transfer and the insulation restricts the transfer of heat energy through the roof by creating a barrier between spaces of different temperature (Osmundson, 1999). The insulation acts as a thermal break and reduces condensation on surfaces that are exposed to both hot and cold on opposite sides (N. Dunnett & Kingsbury, 2008). Green roof systems add mass and insulation over the structural decking, but cannot replace the insulation because their insulating properties depend upon depth and moisture content of growing…show more content…
Dunnett & Kingsbury, 2008). It should absorb and supply nutrients and retain its volume over time to encourage plant growth. Traditionally, welldrained sandy loam was used as the growing medium for a green roof(Cantor, 2008). Its weight and ability to clog drainage layers and fabric lead to use of organic matter as a growing media. Lighter less rich and more porous mixes than soil reduce weight of the growing medium and save cost of structural support (Snodgrass,

More about Green Roof System Analysis

Open Document