For maximum ROI on green roofing, pay attention to maintenance
Written by Mark Southwell   
Thursday, 29 September 2011 10:24

The benefits of green roofing have been extensively researched and promoted in the last decade. Living green roofs are increasingly being retrofitted to existing buildings and more frequently specified in new build projects

Often overlooked in the design and installation is the on-going maintenance for roofs, in particular for extensive green roofs which are oft-times described as “no maintenance” or “self-sustaining”.  Extensive green roofs are engineered to be LOW-maintenance, not no-maintenance.
Enviromat supplied approximately 70% of the sedum matting installed on commercial green roofs in the UK over the past decade, with an on-going research and development program, Enviromat are well placed as specialists in the field of green roof maintenance. 

The UK GRO Green Roof Guideline published in January 2011 stresses that maintenance should be considered at the design stage to ensure that the appropriate management of the established roof is affordable and achievable. However, at Enviromat, experience has taught us that the need for green roof maintenance is frequently not being communicated to the buildings’ facilities managers.

“Environmental benefits of green roofing are almost entirely reliant on healthy plant populations” says Mark Southwell, Green Roof Manager at Enviromat. “It stands to reason, that if the plant coverage is lost, then carbon sequestration stops, the roof loses much of its biodiversity value and the aesthetics are negatively affected.  There is also a risk that without plant roots to stabilise it, the growing medium that helps insulate the building and protect the waterproofing against damage from UV light, will be eroded”.

As with any aspect of buildings maintenance, the cost of reinstating a neglected green roof is likely to be higher than the cost of a regular maintenance regime.

“All Enviromat green roof maintenance contracts are bespoke” reports Southwell “most cost less than £2.00/M2 per year, and the cost will be partly offset by the savings made in heating/cooling the building”

A typical maintenance regime for an extensive sedum roof consists of two visits per annum by an experienced trained operative to apply a specialist plant feed, remove any unwanted plants and ensure that drainage outlets are clear of debris.
Extensive green roofs are installed on to a shallow layer of growing medium.  This reduces the weight of the green roof build up and makes it difficult for weeds to survive long term. Drought tolerant plants are less able to benefit from the carbon and nitrogen cycles that occur naturally in a deep soil layer that is rich in organic matter. It’s essential to apply a specialist slow release plant feed once a year to keep the plants functioning and healthy. It is important though to tailor the fertiliser to the needs of the plant and the conditions on the roof. 

Green Roof Maintenance visits also involve removing excess vegetation, such as tree seedlings that could, in time damage the waterproofing with their roots, as well as checking for signs of drainage problems, weather damage, wind uplift etc.  It’s also vital that firebreaks and drainage outlets are kept free of vegetation and debris.

Enviromat provides a nationwide service and undertakes ad-hoc and regular maintenance contracts across both the public and the private sector.  Clients include universities, hospitals, colleges, schools and commercial buildings.

For more details, visit the website at or contact Green Roof Manager Mark Southwell at This e-mail address is being protected from spambots. You need JavaScript enabled to view it to arrange a free site visit and assessment


Add this page to your favorite Social Bookmarking websites
Digg! Reddit!! Mixx! Free and Open Source Software News Google! Live! Facebook! StumbleUpon! TwitThis Joomla Free PHP
Last Updated on Thursday, 29 September 2011 10:27

Add comment