Living roofs are interesting natural building solutions. Nothing informs the casual beholder better about the ecological mindset and attitude of the home owner. Yet, there are practical values as well that make a living roof a natural building option to consider.

First of all, it should be noted that the very best characteristic of the natural roof is also its worst. Even though it can be and is a very strong ecological statement, it might be way too much for the regular home owner who might otherwise favour alternative and low-cost building, but who is not too keen to wear the associated label.

Nonetheless, natural roofs do have their benefits. A living roof is comprised of a waterproof membrane that is covered with soil, sod or similar materials and most importantly with vegetation. Living roofs can look stunning if somewhat rustic. There are many examples of this type of roof from Scandinavia and the British Isles where they have been used in building for centuries.

Perhaps strangely enough, greenroofs best qualities manifest themselves not in rural, but urban areas where they are most uncommon and difficult to blend into the cityscape. First of all green roofs provide active biospheres in urban environments that usually lack it. Everything green uses CO2 and transforms it into oxygen. Additionally living roofs filter out toxic substances that might be contained in rainwater, thus creating a sort of living filter. Living roofs maintain and hold large quantities of water only releasing it gradually, meaning that less water reaches the streets which can be important in cities with large precipitation. They also function as active coolers absorbing heat, whereas standard metal roofs reflect heat and re-emit it to the atmosphere being one of the reasons why cities are generally hotter than the countryside. Another benefit that is possibly more important for the homeowner is that they provide more than average insulation values and they have also significant noise reductions properties. So, whereas one would think that a living roof should be a solution for the countryside, it really is best in a big city lacking natural growth. Unfortunately not all local building codes encompass this.
Living roofs do have their setbacks, the main being the cost. A green roof can cost double to standard roofs meaning that this is by no means a low-cost solution, but quite to the contrary. Also, green roofs are immensely heavy due to the weight of the vegetation, but even more so because of the collected rainwater. This means that not every house is capable of carrying such load and heavy structures are required to uphold such mass. Also, a living roof needs more or less constant maintenance the same a garden does. The roof may still function quite well if left alone, but it will not improve its looks. Depending on the choice of plants, the roots may damage the waterproof membrane causing leaks. Uniquely in construction, a living roof can be a natural habitat for all sorts of pests and insects that as a next step can and will infest the house.

All in all, living roofs have some strong points in their favour, but the additional cost, the care needed and the possible setbacks must be taken into consideration.