This green roof on an extension in Welwyn Garden City is nearly 10 years old and has been thriving. This was the first green roof I made so I was a little cautious about the loading, the middle are is sedum on a foam drainage mat with very little soil. The edges have more soil and substrate so they are able to support wildflowers, grasses and self seeded local plants. Nowadays I would add a lot more substrate but it is still going strong and the recent rain and sunshine combination has got it growing beautifully.
The sedums are quite persistent and even managed to self seed and create a little patch of growth on the gravel driveway which looks great and offsets the potted plants.
This one was retrofitted which encourages caution, you don’t want the roof to fall down but you can find a combination of plants and sedums that will work on almost any flat or gently sloping roof. Even better if you are building a new extension you can specify the roof to take any depth of soil you want for a really fabulous roof with the plants of your dreams. Drop me a line if you want to know more firstname.lastname@example.org
This was a tiny green roof built as part of a refurb a friend was doing in Stoke Newington. Some nice plants from New Covent Garden and great to have some builders on site to carry all the soil upstairs.
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.
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.
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.
Dry air in the house is a good achievement but I have also been worrying about the pollution levels. Two of the three air intakes are located above the back garden and the front one has some good tree coverage between it and the road but it is still a busy traffic area. This made me look at some alternative ways of cleaning the air, I did some googling and came across the NASA research project on houseplants and their impact on air quality. Now before I go any further I do realise that these were controlled tests and we would also need a very large number of plants to get a big impact but I figure it can’t hurt and what I made looks great.
I have been keen to do something with reclaimed wood and also to add some extra insulation to the flank wall in the kids bedroom so I got a bit carried away here and produced this wall made from old pallets with 50mm of woodfibre insulation behind it. I was a bit nervous about this project as it has a bit more of a design impact than some of the other projects, it’s been in a while now though and I am so pleased with the outcome visually.
The first thing we did was tour the streets collecting abandoned pallets. I found that ones that were slightly broken already were better as they are easier to dismantle than really well built ones. The kids really enjoyed the collection process and I also got them to stain some of the planks we extracted to add some variety to the wall.
Next step was to get hold of some wood fibre insulation, not so easy for small quantities but thanks to https://phstore.co.uk/ for arranging it for me, delivery costs almost the same as the insulation in small quantities but cheaper than elsewhere and charming service too. I then fixed some 50mm battens to the wall at 600mm and push fitted the insulation between.
The next bit involved a nail gun so was great fun managed to charm the lady at Travis Perkins into giving me a discount and I was off. I fixed them in an offset pattern and tried to group similar widths of board together so it wasn’t too bumpy.
Then we had to make shelves for the plants to grow on. I used the ‘dice’ from the pallets (technical term for the square bits that go in between the pallets) screwed into the wall to support shelves made from more pallet boards. These dice are pretty tough and tricky to drill through, one of them still has half a drill bit in it where it snapped.
Once it was all up we put in the plants, I used Chinese evergreen, peace lily, some snake plants and a cutting from an old spider plant. I also put in a watering system! Well, I bought some globes that you fill up and they drip out over a couple of weeks, they are a bit inconsistent but a lot cheaper than some automated system. I top them up with waste water from kids water bottles and they are still growing nearly a year later.
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.
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.
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.
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.
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.
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.
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.