How To Create A Green Shed Roof

Mineral roofing felt on sheds and garages only has a limited lifetime, usually fairly short before it becomes ragged and torn. One way favoured by Martyn Loach to increase its lifespan, and at the same time create a surface with totally 'right on' environmental credentials, is to install a green roof.

Created by Martyn Loach on Sunday, 25th of August, 2013.
Updated on Friday, 19th of April, 2019.


green roof

You may think this is a new idea, but it was first introduced albeit by accident over a hundred years ago in Germany, when vegetation grew in sand used to protect bitumen roofs. 

Look Good And Do Good

On larger buildings, green roofs will conserve energy as well as extending the life of the roof, they can also reduce noise pollution and aid good air quality.

Used on our domestic outbuildings they are green islands for birds and insects, offering food and shelter. In a small way they counteract the loss of natural habitat but, as in the case of the garden pond, this can make a significant difference when added together.

They look good, offering biodiversity in place of tedious barren felt and to a large extent look after themselves. For a shed roof, the work will take perhaps a day and you'll need help at certain stages.

Before you begin, make sure the current structure can withstand the extra weight, don't forget that it will be even heavier after rain. If it's an apex roof the angle should be greater than 3° and no more than 20°. A sunny location is also preferred.

Firstly line the roof with waterproof butyl, this will keep both the water out and prevent the vegetation's roots from penetrating the shed roof.

Now make a simple frame using pressure treated 2in x 4in timber that fits the roof and fasten it to the shed. It's essential that water can drain away, therefore the frame must have drainage holes along the lower sides.

Use a line of pebbles along the edge so the holes don't become blocked. You could also fit a filter sheet that allows the free passage of water while retaining soil particles. A moisture trap of some kind will slow the rate of drainage, these can be purchased but you can also use an old blanket or towel. 

What To Plant

The growing medium is called substrate, on a shed 3ins is enough. It's no good using purely topsoil as that will be too heavy. Mix in up to 80% inorganic material such as perlite, sharp sand or brick dust.

Various varieties of Sedum are a popular choice for planting, as alpines they will grow well in the shallow gritty substrate, maintain cover throughout the year and need little maintenance. A good range of insects will also be attracted throughout the summer.

You can purchase rolled up mats of sedum, if not think about using S. acre (tiny yellow flowers on pale green foliage), the succulent golden yellow S. rupestre or the starry white flowers of S. album.

Wildflowers that can survive in low nutrient conditions are also a consideration, perhaps Cowslip, Lady's Bedstraw, Rock rose, Harebell and Thyme.

Related Articles

How Thrive's Accessible Gardening Changes Lives

How Thrive's Accessible Gardening Changes Lives

The Society for Horticultural Therapy is an organisation generally known as Thrive, and David Coton recently learnt more about their projects, training and consultancy.

Author: David Coton

Written by David Coton.
Published on Thursday, 16th of June, 2016.

Lavatera Olbia Rosea - Put Some Colour In!

Lavatera Olbia Rosea - Put Some Colour In!

Container grown shrubs can be planted throughout most of the year. The choice is huge and, for David Hall, the Lavatera is a particular favourite.

Author: David Hall

Written by David Hall.
Published on Friday, 29th of May, 2015.

The Most Beautiful Clematis

The Most Beautiful Clematis

The beauty of one particular Clematis has enchanted David Hall for many years, Clematis sieboldii or “Florida Bi-Colour” is his queen of the climbers and here he explains why it captivated him.

Author: David Hall

Written by David Hall.
Published on Thursday, 28th of May, 2015.

Why Our Front Gardens Should Be Green Not Grey

Why Our Front Gardens Should Be Green Not Grey

Suburban gardens, once the well kept privet edged pride and joy of the majority of householders, are rapidly becoming paved over according to a recent report from the Royal Horticultural Society that Nathan James Dodd has been reading.

Author: David Coton

Written by David Coton.
Published on Tuesday, 19th of May, 2015.

comments powered by Disqus

Author

Martyn Loach

Editor in Chief

View Profile

RSS

View RSS Feed

Follow Us!

Recent Articles

Review of Rubbermaid Plastic Sheds

Review of Rubbermaid Plastic Sheds

New products are the lifeblood of many industries and it’s no different in the gardening sector and most of us above a certain age will know the Rubbermaid brand well, particularly if you have ever been in the cleaning industry.

Author: Robert Hall

Written by Robert Hall.
Published on Monday, 16th of September, 2019.

David Coton's Review Of Glee 2019

David Coton's Review Of Glee 2019

GLEE is the garden retail industry's annual show at the NEC in Birmingham. David Coton took the opportunity to visit this year's event to catch up on the news, visit current/potential suppliers and evaluate new products we would like to offer on GardenSite in the coming year.

Author: David Coton

Written by David Coton.
Published on Thursday, 12th of September, 2019.

Review of Evika G1 Greenhouses

Review of Evika G1 Greenhouses

I had never heard of Evika Greenhouses but when I walked into our annual Garden & Leisure Exhibition 2019 (GLEE) it was the only product I really saw. A brand new greenhouse brand is always going to get my attention but the sense that this was not only new, but different, kept my focus.

Author: Robert Hall

Written by Robert Hall.
Published on Thursday, 12th of September, 2019.

What To Do In The Garden In September

What To Do In The Garden In September

Although the growing season is slowly coming to an end, David Coton can suggest quite a few jobs that need to be done over the next few weeks, helping you make the most of what's left of summer and preparing for the arrival of autumn.

Author: David Coton

Written by David Coton.
Published on Tuesday, 29th of August, 2017.