Category Archives: Ecology

Green roof on a bike shed

This is a project I completed back in October, secure cycle storage and a green roof. The client wanted secure storage in the front garden without having a big ugly box taking up all the space for planting and we came up with this elegant solution.

Still flowering in March

As the shed is on the way into the house we planted a number of different herbs which can be easily picked when you are on the way home and also release a scent if you brush past. These were combined with some flowering plants (it was October so not much available) and sedums. The whole roof was also sown with wildflower seeds so should be quite productive in the spring. There are saffron crocus bulbs underneath which may start to appear in late summer.

Freshly planted

The bike shed itself has capacity for 2 bikes but there is a larger 4 bike version or these can be put side by side for multiples. To order.

This type of roof can be more easily accessed by the householder so we can try and create a slightly more formal garden than I would on a normal green roof as you can change the plants around and water and feed them if it is necessary.

The green roof itself has a fleece at the bottom then a drainage layer of aerated clay pebbles before the soil, here to about 125mm depth but the sheds are pretty tough so this could be bigger if required. The sleepers look really good but an alternative would be cobbles in gabion cages depending on what would fit with your front garden. Order page.

Gabions and cyclamen, a new green roof in Herne Hill

It’s taken a little while to share this new green roof I built in Herne Hill recently.

There were a number of challenges here particularly the height of the roof with no edge protection, we used a harness to install the edges.

The edges were built using gabion cages filled with cobbles. This created a more natural edge and ensured the stones didn’t roll off the edge of the roof and shatter the tiles below, I think they look pretty cool.

I used aerated clay pebbles for the drainage layer again, really like these rather than the plastic sheets and carrying a bag makes you feel really strong as they are so lightweight. We then put in a protective membrane and covered with ultra lightweight green roof substrate from Shire Substrates.

The roof has been seeded with a mixture of wildflowers and grasses with more to be added in the spring. In the meantime I put in some grasses, sedums and also Cyclamen. I wasn’t really sure about the cyclamen but not much else is flowering this time of year a month later and they seem to have settled in well.

I will add further updates in the spring. There are lots of bulbs in there which should appear soon.

Marlow green roof update

Not all my green roofs are in London, you can see one of my early ones in Welwyn Garden City and this magnificent roof on a garage in Spring Gardens in Marlow

Shows edge detail and flowers
Lots of wildflowers growing here

The roof was installed early this year using Shire substrates and materials from Optigreen. I used expanded clay for the drainage layer and large cobbles to create a more natural looking border.

Wildflowers and sedum

The roof had loads of really nice seeds in it and was also planted with some sedums, aliums and stipa grasses and it has really blossomed tremendously.

the long edge of the roof

Green roof in Wood Green

This is one I did last year that has been growing really well. The roof was on a new extension so the clients were able to design in extra big joists so we could support a good depth of soil on the green roof.

They managed to get a 5m extension so we had a good size to work with even with the skylights. It was waterproofed by the contractor ready for installation.

Roof before adding the greenery
Roof cleaned and prepared for installation

The team and myself laid out a protection fleece made from recycled material on the roof, then we added a drainage layer and put a filter fleece on the top to stop roots growing into it. Then we added the substrate, a special mixture of soil, lightweight aggregates, brick chippings etc, this is designed to keep the weight down, drain easily and also stop the plants growing too tall and need maintenance.

The team lay out the substrate

We put a gravel barrier round the edge of the roof and the skylights to assist drainage and add a firebreak. We also put extra gravel under the downpipe from the main roof of the house so the roof can absorb all the water from the roof rather than have it fill up the drains.

Moving materials is always a problem in London and we had to carry all the green roof substrate through the house and up on to the roof. Luckily Ecoalex has some good strong assistants so I didn’t have to do too much lifting. Once we had put out all the green roof substrate at varying depths we were ready to plant.

Planting, workers grass
Roof ready to be planted

For this roof I had a mixture of mature plants and seeds. I included some Stipa tenuissima (the grassy stuff in the foreground) for the first time to see how it would grow and although it browns a bit in the dry periods it seems to be thriving. We also put in a few varieties of sedum to get some ground coverage including house leeks. Other plants included sea burnet and Sempervivum. I picked up all these plants at New Covent Garden Flower market in the morning a great place to pick up plants in London. But these are just to start the roof, the main coverage will develop over the next three years with all the green roof seeds we have planted I used a couple of mixes of native wildflowers including this one from Scotland that has 20 wildflowers and 3 grass species in the mix . Not all these will thrive initially but over time they should each find their own niche on the roof and grow nicely. Gary Grant likes to describe these seed mixes as an orchestra with all the instruments waiting for the conductor to call them in at the appropriate time in the green roof’s own symphony. Below are some pictures of the roof planted and how it has developed this year. More will be added over time.

Low impact green roof in Marlow

Lots of green roofs going in recently and I need to spend more time documenting them. This one in Marlow on a garage was a new design that I am quite pleased with.

I have been working for a while to reduce further the plastics going into a green roof. I used to work with SUDS (Sustainable Urban Drainage Systems) a lot in the past and one thing I always noticed was the number of pipe manufacturers trying to shoehorn more plastic into natural drainage systems. Roofs obviously need to be waterproof so I can’t change that bit and we need something to protect it from sharp objects etc. Then comes the drainage layer which is lots of plastic sheets, this is important to hold a bit of moisture but also to makes sure it drains effectively. So drainage is important for weight but maybe we can make it of something else. For this roof we used aerated clay balls wrapped in a filter sheet that is held in place with some extra large cobbles. So the plastic is at a minimum.

The cobbles add a really nice touch to the edge of the roof and enhance the appearance considerably especially on a roof like this where there is no parapet. The soil is also held in place by the cobbles and I guess some of it may wash between them but not off the edge of the roof.

The roof has been planted with about 15 different plants, some sedum and ornamental, seeded with 30 different wildflowers and also bulbs planted to come up later in the year. I am monitoring progress and plan to pick up some crocus bulbs in autumn to plant.

Finished roof

If you like the look of this, drop me a line or give me a call 020 8133 0190 and I can see what we can do for you.

Extension in Kennington with green roof

I went to visit an extension in Kennington which has the biggest domestic green roof I have built. There are some very big skylights so it isn’t all green but it looks great. This first picture shows the rear extension with some rather fine timber cladding, you can see the plants poking over the top of the coping stones:

IMG_20160718_143650.jpg

The combination of rain and sunshine we have seen this summer has been really good for the plants, even if people haven’t been so happy. I missed the peak flowering of this roof but there were still plenty in bloom on Monday. The clients daughter has a bedroom window looking out onto the roof and has been enjoying the developing scene.

IMG_20160718_143829.jpg

The skylights really bring light into the house and the kitchen looks even bigger than the space the extension added on. You can see some of the plants waving in the breeze around the sides when you are having dinner.

IMG_20160718_143606.jpg

IMG_20160718_144054.jpg

Reclaimed materials in side return extension in Hackney

A side return infill extension with an industrial style. Extensive use of reclaimed materials, high standards of insulation and a wildflower green roof.

We completed this project late on last year working with Clements Design as the architects.

The project aimed to turn a cramped kitchen into a spacious area for cooking, eating and socialising. There is an industrial and sustainability theme to the project, the materials used are often from or designed for factories. Electrics are contained in galvanised metal conduit and the floor is concrete. Walls are exposed brick, both reclaimed glazed brick and the existing London stock bricks revealed to the world. The large glass panels to the roof draw in light to what was once a dark area and bring out the rich colours in the reclaimed wood cladding.

Though the materials could be seen as austere they are softened by the contents of the room that reflect family life, there is space for a large wooden toy stove, a comfy sofa and a gorgeous oak dining table with mismatched chairs.

The large rear doors mean the garden can be seen and accessed easily from the house, the doors can be flung open in the summer for barbecues. The green roof will develop over time but already has wildflowers peeking over the parapet and they can be seen swaying through the glass roof.

The project was also designed in conjunction with the neighbours and they share the party wall and the box gutter.

Sustainability was a key part of the client’s aim for the project. Reclaimed materials were used wherever possible. All the bricks removed in the demolition stage were cleaned and re-used onsite to build the new structure. Internally there are two walls of glazed bricks reclaimed from a lift shaft in Kensington. The other walls are the original brick exposed and insulated on the outside where appropriate. The bi-fold doors are triple glazed with a u-value of 1.09 are factory finished for long life and are made from environmentally sourced timber from sustainable forests. The heating is underfloor and utilises the existing condensing boiler, three Nest controls were added to the system to control this and create two new heating zones in the house.

The wood (for drawer fronts, shelves and cladding) is from a reclaimed wood specialist in Guiseley, Leeds, called Machells and is cut down from Yorkshire Victorian mill joists.

The large pendant lamps are reclaimed from a 1950’s factory in the Stoke area.

The table was made in Leeds from British oak 35 years ago.

All the shelf brackets and drawer handles were made in England in foundries using all traditional methods.

All lighting is LED, even filament style traditional bulbs are actually LED.

The green roof is part plug planted and part seeded with a mixture of wildflowers, meadow plants and some sedums. The roof will flower through most of the year and provide habitat for insects and foraging for birds amongst other biodiversity benefits.

Nine months in and this green roof has been thriving

I went to see the roof I built in Kennington last month and took some photos I thought I would share. I wrote about this one last year showing the build up process to a green roof. I was particularly pleased that the insulation we put on as an added extra has made a real difference to the householders, the side return was previously a no-go area in the cold winter months but has now become habitable with the added warmth.

Anyway here are a few photos to illustrate how well the roof has been growing over the last nine months:

The flowers are growing well including the grape hyacinth
The flowers are growing well

A really good selection of wildflowers has sprung up
A really good selection of wildflowers has sprung up

Maybe I should have made the middle access a little narrower
Maybe I should have made the middle access a little narrower

Overall I am delighted with the roof and the clients are really pleased too. The roof has already developed really well and should develop further over the next few years. The roof should reach maturity after three years but different plants will dominate in different years and seasons.

If you want your own green roof give me a ring on 020 8133 0190 or drop me an email alex@ecoalex.com

 

 

Green roof in South London

Last week I completed another green roof in Streatham. It is on the rear of a really interesting house, a 1930s semi that is getting a complete eco-makeover from the owner. He has insulated the walls inside and out with wood fibre and remade the roof in solar panels and that is just the start. All Stephen’s neighbours find it hard to believe how warm the house is without loads of heating!

Anyway, last Wednesday he set aside so I could come along and help him build a green roof, here are the photos:

The roof is on top of this single storey extension
The roof is on top of this single storey extension

The first layer of the green roof, a fleece to protect the waterproofing and retain some of the water.
The first layer of the green roof, a fleece to protect the waterproofing and retain some of the water.

Then we added a drainage layer to encourage free draining.
Then we added a drainage layer to encourage free draining.

Next is the root barrier and then special substrate
Next is the root barrier and then special substrate

We planted the roof with sedums, widlflower plugs and sowed a selection of wildflower seeds
We planted the roof with sedums, widlflower plugs and sowed a selection of wildflower seeds

The finished article
The finished article

It should grow and develop over the next few years until it reaches maturity.
It should grow and develop over the next few years until it reaches maturity.