Enviromat Blog

What sort of green roof is best? Pitched, Flat or Curved?

December 9th, 2011

Designing a green roof, pitched? flat? or curved?

December 9th, 2011

Green roof being fitted on to a curved roof Enviroden

Green roof design is so much more than just making a building look good.  For a green roof to really work well it’s imperitive that the building structure and the plants themselves are matched.  The building design must ensure that the plants have everything they need, the green roof build up must not compromise the structure of the building.

The weight of the green roof build up is probably one of the biggest concerns.  The Enviromat green roof build up weighs only 65Kg/m2 when saturated. That means that the  load bearing capacity of the building needs to be 120Kg/m2 to allow for live loading, but it is still one of the lightest green roof systems in the UK and it’s proven to work.

The Enviromat sedum roof system does behave differently on flat and pitched roofs though.  Not only is the build up slightly different, we have found that a pitched roof needs a little bit more maintenance than a flat roof.  We have two test roofs on the farm.  They’re side by side, so they have the same amount of sunshine and rain.  One is pitched, the other is flat.  Now, on a garden building, a pitched green roof is more easily seen from the ground and makes quite a nice feature, but, it doesn’t hold water or nutrients quite as well as a flat roof and the plants get stressed a lot quicker in hot or dry weather.

Flat green roofpitched green roofThese two pictures were taken yesterday (8th December 2011). The roofs have had exactly the same treatment throughout the year and you can see that on the flat green roof the plants are greener, there coverage is more dense and although it perhaps doesn't show so well in a small pic, there are more sedum species showing themselves on the flat roof than on the pitched roof. So, what is the compromise between keeping the roof as green as possible - ie flat roof; and being able to see it from the ground - ie pitched roof? One solution is in the maintenance....if you go for a pitched roof, be prepared to irrigate it more often and feed twice a year instead of just once. All that fertiliser and extra water though, is not necessarily as environmentally friendly as it could be. OR Try a curved roof...........It's visible, it's very attractive, it's very strong and has a gentle pitch that keeps irrigation requirements sensible. Enviromat have been working with a Company in North Norfolk who have developed a beautiful curved roof design. Enviroden can produce a bespoke building, strong enough to take a green roof, even if the client doesn't have enough budget to install the green roof right away, they can be confident that the Enviromat build up can be installed at a later date.The Enviroden website is at http://www.enviroden.co.uk/ and is well worth a visitEnviroden log store

Great new book about Green Roofing

November 28th, 2011

I’ve been reading “Green Roofs, A guide to their design and Installation” by Angela Youngman, and from now on this book will stay by my side as a fab source of facts and figures.  In fact I thoroughly recommend it.

The photography is superb, the subject has been thoroughly researched and almost every point is backed up with a case study. 

This New York Biobus doubles as a mobile green roof

My favourite picture of all in Angela Youngman’s book is of the Biobus…with the Carbon Reduction Conference happening in London tomorrow (29th November 2011) I can’t help wondering if the powers that be will take notice of Marc Castro Cosio of New York who’s idea is to create mobile green roofs on top of buses.  He comments “if we grew a garden on the roof of every one of the 4,500 buses in the MTA bus fleet, we would have 35 acres of new rolling green space in the city”  Imagine that!  Each bus would sequester some of its own carbon…fabulous! The photo on the left was taken by Marc de Castro

Another thing I like about Angela’s book is that there is a whole section on maintenance requirements. Maintenance is something that is sadly overlooked in the excitement of installing a green roof, but just as one wouldn’t dream of putting axminster carpet in the living room and never cleaning it, it is madness to spend hundreds (or even thousands) of hard earned money on a green roof and then not caring for it.

For hints and tips on seasonal green roof care, go to http://www.maintenanceforgreenroofs.com/ or check out my other blog http://greenroofmaintenance.wordpress.com/

Oh, and don’t fr

Pictures of Enviromat taken in early november

November 2nd, 2011

Wow! there’s no doubt about it, the sedum species in Enviromat certainly give a long flowering period. Check out these pictures taken on the Enviromat production field on 1st November 2011…..these will provide a welcome meal for any pollinating insects still buzzing around at this time of year

 

 

sedum pulchellum

sedum album flowering in november

sedum album close up of star shaped flowers

Green Roof Maintenance

November 2nd, 2011

Owners of Green Roofs should be aware that their roof is “low maintenance” not “no maintenance”. Green Roofs have all the benefits associated with their abundant sedum plants including insulation, attracting wild life and they do not need a great deal of maintenance.

Firstly you need to understand that sedum plants do look different throughout the year and your roof may not always be “green”. It will look its best in the Summer and Spring months and in Winter months it may turn reddish-brown. Your first task in Spring is to feed your living green roof to make the most of it during the rest of the year. At the same time you need to weed out any unwanted plants and weeds. These are generally low in number but can make the roof untidy if left.

If you have any gaps now is a good time to plug them with new sedum plants or cuttings to keep it consistent. The next job is to inspect the whole roof area and remove any unwanted
debris, leaves, branches, litter, etc especially around gutters and drainage outlets so that rainwater is free flowing and going where it should do. Finally apply a slow release, low nitrogen fertiliser to your plant area. The quantity will depend on how old your green roof is so it’s best to check with your supplier.

We suggest that debris is removed and drains are cleared twice a year and the roof is fed once a year, depending on size and location. So good luck and if you need any help then contact us or visit http://www.maintenanceforgreenroofs.com

How to make a green roof video

October 20th, 2011

We’ve been having a fabulous time creating a “how to make a green roof” video with Adam and Rich from Cambridge Filmworks. If all goes well it should be uploaded to Youtube in time for next week’s Creating Landscapes show at Capel Manor near Enfield. I’d like to be able to use it in my seminar on Enviromat and green roofing.

I can’t thank Nigel and Lucy enough for letting us use their Enviroden for filming. It’s an amazing building, really well designed and built to the highest standards.

Mark and I had an early start to the day (being picked up at 7.30am was painful) and we joined Adam on site at 8.30. Chris followed on after he’d done the school run. The weather was on our side all day long – how lucky were we?

I can’t wait to see the finished video, 8 hours filming and another 8 hours editing will give us a video approximately three minutes long but there’ll be plenty of footage “in the can” if we want to make another film.

measuring and cutting water retention blanket

Chris takes a break

This green roof is three years old and still looks good

October 10th, 2011

Yesterday I visited a sedum roof in Stevenage that was first installed three years ago – and I have to say, it looks fantastic.

When the living green roof was first installed using Enviromat sedum matting,  it was a small green oasis in the middle of this huge 70′s housing estate, and three years on, things have only got better.

The green roof build up was very simple.  It’s a flat roof, so drainage mat went down first, followed by water retention mat and finally, a layer of Enviromat sedum matting.

sedum roof in Stevenage immediately after installation

The Enviromat was watered in, and since then, the only maintenance it’s had has been an annual application of Nutrifusion sedum feed and twice-yearly checks to make sure the gutters and drains are clear.

Green roof, three years after installation

The owner is delighted to report that the roof has flowered beautifully, all summer long attracting butterflies, bees and birds.  It also does a terrific job of insulating his extension against heat and cold. 

There’s a little bit of grass amongst the sedum plants – probably because we’ve had some wet weather lately.  As soon as we get a nice long period of drought, the grass will die out.

Hats off to Enviromat.

To learn more about creating a living green roof like this one visit www.enviromat.co.uk or e-mail me for a free copy of our CD ROM.  Oh- and watch this space……..we’re filming a “how to” video later this week which should go live online before the end of October 2011

Preparing a green roof for winter

November 11th, 2010

As I lay in bed this morning, enjoying the first cuppa of the day and wondering if today will be the day when my new grandson decides to arrive, I saw the very last leaf fall off the rowan tree on the village green.  Well, it didn’t exactly fall.  The weather here today is wet, windy and miserable and the poor little leaf was ripped from its branch and propelled at speed to goodness only knows where.  But I digress.

Heavy rainfall, fallen leaves, and the fact that I have an appointment in Cambridge tomorrow – on top of a green roof – reminded me to remind everyone out there who either owns or cares for a living roof (particularly if it’s a sedum roof) to spend a little bit of time on maintenance this autumn.

Sedums are easy going little plants, that’s what makes them ideally suited to green roofing, but they don’t like having soggy roots and they don’t like being kept in the dark.  So as soon as you get the chance – ie when the roof isn’t windswept or slippery with rain – please please please check that the drainage outlets are clear and that any fallen leaves are removed.

gazebo with a green roof pictured in JulyI recieved a beautiful picture this morning of a gazebo with an Enviromat green roof that has been beautifully maintained.  Three years after it was installed it looks better than ever. An occasional watering and an annual feed have ensured that the sedum plants have withstood temperatures of minus fourteen, they’ve tolerated heat and drought and whatever else the elements have decided to throw their way – and they look spectacular.  Well done to Penny Bennett Lanscape Architects who designed, installed and maintained the roof -a little bit of TLC has paid dividends.

Cost savings of green roofing

October 28th, 2010

I recently subscribed to Dave Hilary’s course of Green Roof Lessons via his website www.greenroofplan.com and I have to say, I like the way he breaks down the benefits of green roofing into simple, easily understood, bite-sized pieces.

Here’s an extract from “Lesson 2, Extensive Green Roofs are an Easy Call” 

The cost-benefit analysis is likely to be your driving factor
behind choosing an extensive green roof. The factors to look for
include:

Rooftop replacement
Rooftops have to be replaced frequently due to the impact of
sunlight, especially ultraviolet (UV) rays. That’s right, the same
wavelengths of light energy from the sun that cause skin cancer
also cause your rooftop’s underlying material to break down.

Heating costs
A green roof is likely to cut your heating costs by helping to
retain natural heat, plus the heat that you pay big bucks to bring
into your home. The green roof is like a hat on a bald head – it
retains warmth, cutting your costs.

Cooling costs
With a green roof, your house never heats up so much when the sun
beats down on it. This reduces not only the cost of running your
air conditioner, it reduces roof replacement costs by lowering peak
high temperatures.

An extensive green roof keeps you off the peaks, and therefore is
likely to save you money. It also features lower costs for
structural strengthening, setup, and maintenance. You can always do
more later if you decide to do so, but an extensive green roof is a
worthy starting point – and perhaps ending point – on your
adventure.

All of these points and more are covered in Dave’s e-book which is downloadable from his web site and they’re also incorporated into Enviromat’s Green Roof Information Days.

The next Green Roof Information Days are on 23rd November 2010 at The Berkshire College of Agriculture and again on 1st December 2010 in Hockwold, Norfolk.  There’s no charge for either of these events, but places are limited so if you fancy coming along, please let me know so that I can reserve a place for you.  E-mail me on sales@qlawns.co.uk or phone 01842 828266 – hope you can make it……..

A cure for baldness

September 9th, 2010

If the weather this summer has left your sedum roof looking a bit bare in places, you certainly won’t be alone in wondering what to do. But never fear – if you act quickly, you should be able to remedy the problem with very little cost or hassle.
Sedum plants are drought tolerant, but they’re not drought proof and several Enviromat customers have noticed that some of the plants perished in the hot dry spell that the UK enjoyed earlier this summer.
Now that the weather has changed for the better (from a plant’s point of view that is), conditions are just perfect for regenerating sedum roofs from cuttings.
Simply break pieces off the healthy plants and press them into the growing medium where plant coverage is sparse. They’ll soon root in and will happily begin to grow, ready to adorn your roof next spring.
This is the ideal opportunity to choose your favourite species and multiply them on the roof. I like s. pulchellum for its firework shaped pale pink flowers in early spring and again in late summer. I also love s. spurium with it’s plate-like flowers in summer, such vibrant colours and so popular with butterflies.

Enviromat sedum matting sets the scene at MiniWorld in Legoland Windsor

And if you don’t fancy climbing on to the roof to spread cuttings – or if you have more bald bits than plants, the Enviromat maintenance man will be pleased to advise you. Contact Mark on 01842 828266 or e-mail a picture of your roof to sales@qlawns.co.uk