How to turn your grey, gravelly supposed to be green roof into a lush green roof again?

Sempergreen USA is able to turnaround a “dead” green roof into a vibrant, lush green roof! Years of experience enabled us to be the nr. 1 green roof supplier, installer and remediation expert.

Alexandria, Virginia| instead of offering a green roof renovation, by altering the soil composition, rebalancing the nutrient levels, improve irrigation, add new vegetation and appropriate maintenance. The client decided to take advantage of the current poor conditions and overhaul the entire layout of the roof and incorporate green walls as well. Sempergreen USA installed approximately 2,500sf of green roof and 120sf of green wall.

Project description

In the spring of 2021 Sempergreen Services, who had been a long-term service provide to Erkiletian Development Company, was asked to provide a proposal for a substantial renovation of one of the amenity decks at the Asher. Initially Sempergreen Services would have focused on renovating mostly the vegetated green roof area but as conversations with the client continued the scope of work for Sempergreen Services evolved to a much more extensive one including several hardscape items like Concrete and Ipe pavers and artificial turf.

The most obvious problem with the amenity deck at the Asher was a failing vegetated roof system resulting turning the area that was supposed to be lush and green into a grey gravelly moonscape. The identified problem with the existing system, that was installed years ago by a competing green roof supplier, was related to the inappropriate soil composition making the area rather hostile for the designated plants species. Though Sempergreen Services would have been comfortable offering a green roof renovation by altering the soil composition, rebalancing the nutrient levels, improve irrigation, add new vegetation, and appropriate maintenance, but the client decided to take advantage of a current poor conditions and overhaul the entire layout of the roof.

The new design

The newly designed amenity deck would consist of a new layout with some additional areas of concrete pavers, a refresh of the Ipe paver path plus three outdoor shower/mister stations, two new artificial lawn areas and a fully renovated green roof assembly on the remainder of the roof areas. To compensate for turning some of the original green areas into paved areas within the new design, the client decided to add another green roof area slightly out of sight behind the mechanical equipment.

As the conversations with the client progressed the idea to also add some vertical planting to the project came up. Several options and locations were considered until we finally ended with the idea to add four separate walls to break up the slatted wood fence.

Plant supply and propagation

Sempergreen Services pre-grows all its own living walls. The starting material, typically 72-cell plugs or 2” pots, is planted into the panels several months before scheduled installation and grown in a vertical setup at a Sempergreen Nursery to ensure plants are well established by the time they are installed on the project. The Asher Living Walls were grown by our main nursery in Culpeper VA.

For the green roofs Sempergreen Services used all Sempergreen grown plants. The base layer of plants for the green roofs was the Sempergreen Standard sedum blanket. In addition to the sedum blanket, to improve the biodiversity on the roof, add dimension to the green roof and add interesting architectural features, Sempergreen services interplanted the green roof with a mix of pollinating plants.


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Experts in the field of green roof remediation and green roof installation.

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We grow sedum and deliver the total package of a green roof structure

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Pre vegetated