green roof on conservatory by the Urban Greening Company

Domestic Green Roof Installation & Design

There are a growing (no pun intended!) number of reasons you may be interested in installing a green roof on your home. It maybe you feel that it is the environmentally good thing to do and wish to help restore biodiversity in your area. Or you may want to provide extra insulation and protection for your roof, especially as energy costs continue to rise. It maybe that you want to reduce the stormwater runoff from your roof to mitigate urban flooding. Or maybe you want to boost a planning application approval.

Whatever the reason, installing a green roof is becoming a legitimate choice for homeowners and families. Offering long life protection of your roof, stormwater management, insulation and a stunning visual appearance for your home.

And a green roof is not the end of your options with the option to add solar panels turning your green roof into a bio-solar roof, or if you have a suitable flat roof even a roof terrace or elevated roof garden for you to enjoy.

Installing your Green Roof

Green roof in progress showing many elements of the installation

At The Urban Greening Company we have many years’ experience installing all types of green roofs; large, small, extensive and intensive. The type of roof you will need or be able to install will depend on a range of factors. When you contact us we will talk you through the options and assess the most suitable solution for your roof. If you need planning permission or a structural survey, we will advise you on this and can help arrange for a structural report to be done for you.

Benefits of Installing a Green Roof on Your Home

green roof reduces Co2ENERGY SAVING

In addition to looking great one of the most significant benefits of fitting a green roof is to your budget. Green roofs and the accompanying layers that go with it are brilliant natural insulators (just ask a rabbit!) They keep the house warm in winter, preventing heat you have put into your home from escaping and saving you heating costs. And green roofs are great at keeping your home cool in the summer. Depending on the level of soil, moisture and growing membranes they can act as a great barrier to external heat. All of this reduces the CO2 that is pumped into the air on your behalf through energy use when you are heating and cooling your home!

green roof noise benefitsREDUCED NOISE POLLUTION
And all that natural green insulation also helps reduce noise pollution, both the noise you hear and the noise you make. The soil, grass and plant layers provide brilliant natural sound proofing.

green roof storm water mitigationFLOOD MITIGATION

Rain and storm water runoff are becoming a problematic issue, especially in urban and built-up areas. Green roofs are very effective at reducing the amount and speed of the water that runs off the roof of your home. Combined with a “Blue Roof” type install storm water can be significantly and effectively managed. As our weather gets wetter this will become a vital tool for homeowners and urban planners in the future. In addition, the retained water can be used to provide vital moisture for the growing grass on your roof saving on irrigation and associated costs.

green roof biodiversity benefitsINCREASED BIODIVERSITY

It goes without saying that we are increasingly aware of the importance of biodiversity in nature, not least to ensure our food supplies are successfully pollinated. A green roof, especially a wildflower green roof, can provide much needed biodiversity particularly in built-up urban areas where green space has been slowly disappearing over the years.

green roof pollution busting benefitsCLEANER AIR

Another excellent benefit of installing a green roof on your home are its’ pollution busting properties. The Sedum, grass or wildflowers and their growing medium, depending on the type of green roof you install, all provide natural pollution filtering properties, providing a vital contribution to cleaner air in many towns and cities.

Types of Green Roof

There are several types of green roof you would normally install on a home:

INTENSIVE GREEN ROOF

An intensive green roof is essentially a garden or park type area on a rooftop, and they are often designed and intended to be enjoyed or used in person. When installed these roofs have deeper soil layers and can support a wide variety of plants, including grass (as you would expect), shrubs, and even small trees. These are less common for domestic green roof installations due to the extra structural challenges and maintenance involved.

EXTENSIVE GREEN ROOF

An extensive green roof is a type of green roof designed to be lightweight and low maintenance. These types of living roof are much more common and are comprised of primarily low-growing, drought tolerant plants such as sedum and hardy grasses or herbs.  This type of green roof also includes wildflower and biodiverse green roof types. There are a wide range of systems available to facilitate the installation of this type of roof.

INTERMEDIATE GREEN ROOF

An intermediate green roof type that can include characteristics of both extensive and intensive roofs.

How We Install Your Green Roof

Green roof installation can be carried out using a variety of different systems from built in place custom installs to modular tray systems (More normal on a domestic green roof), but they all follow the same basic installation steps.

  1.  Waterproofing & Protection: The roof must be clean and watertight before commencing anything else. As the roof is probably a flat roof it will have been exposed to water and UV rays for far longer than a normal pitched roof so it will need a thorough inspection before anything else can happen. Any weak points or damaged areas will need to be repaired and made good. An additional waterproof coating maybe added such as a waterproof rubber sheet (EPDM). The existing drainage will need inspecting and possibly updating.

EPDM Roof waterproofing

  1.  Root Barrier: In most cases but especially where bituminous waterproofing is used, a “root barrier” will be installed. This is a tough, multilayered and puncture resistant sheet or similar to protect the watertight roof layer from the roots of whatever is going to grow above it.
Root Barrier being installed over watertight layer

Root Barrier being installed over watertight layer

  1. Drainage and Filtration: Drainage mat is a lightweight layer that does exactly what its name suggests. It allows excess water to drain away from the plants and channels it into the roof’s own drainage system which will be installed around the edge of the roof.  The drainage layer will also include a filter fleece which simply prevents soil and other debris clogging up the filtration. This could cause waterlogging that can kill-off some of the roof planting.
filter barrier ready for modular green roof planting crates

Filter barrier installed. Gravel bags around the sides ready to provide the green roof edging (See next step).

  1. Gravel Edging: A gravel edge will be added to the roof to facilitate efficient drainage and to keep the plants and soil from fouling the guttering, downpipes and eaves of your home. Consequently, it also stops the soil from being washed away from the main planted roof area.
green roof gravel edge

Gravel edging

  1. Substrate: The substrate, or growing medium, supports the growth of the grass or plants that will make up your green roof. A substrate is a soil alternative designed to be lightweight, so as not to put too much strain on your roof,  yet nutrient-rich, providing an ideal environment for the plants to thrive.
St Botolph Without Aldgate Community centre roof turf ready to lay

Light weight Substrate down and green roof turfs stacked visible behind ready to be laid over it.

  1. Vegetation: The final and most visible part of your green roof is the vegetation or plants. If a Sedum roof is being installed then sedum blankets will often be used. These are rolled out on top of the substrate just as if you were having a lawn returfed. If many different plants are to be used, such as for an “Intensive” style green roof then pre-planted modular interlocking trays may well be used instead.  (In some cases the substrate my be combined with the trays)
green roof installed and looking glorious

A Green roof install finished by the TUGC team and looking glorious

Once complete the roof will be watered and fed. In some cases, it may be recommended to add an irrigation system. An ongoing maintenance plan will also be advised on to ensure the roof establishes and thrives. We will also arrange to return after a certain amount of time to check on everything and sort out any teething problems or unforeseen issues. At this point any struggling plantings will be attended to and, if necessary, replaced.

SOME REAL WORLD DOMESTIC GREEN ROOF EXAMPLES

Some examples of our Domestic Green Roof Installations and remedial work are below. Please contact us if you would like any further information or to discuss a project with us.