- How to Install a Green Roof
- Case study: How to install a green roof on a private home
- How To Make A Green Roof
- BUILDING A GREEN ROOF
- Create a Green Roof
- Recommended Articles
- Procedure for Building a Green Roof
How to Install a Green Roof
A solidly engineered roof helps protect your house against the elements, of course, but the one installed over Sarah Jack and Scott Harris’s eat-in kitchen does that and more. Planted with hundreds of low-growing succulents, the little flat-roofed extension off their 1925 Colonial Revival helps slow down and filter rainwater runoff. Residential green roofs such as theirs protect natural waterways from oily street residue by lessening the chances that municipal storm-drain systems will overflow. It also keeps the room below it warmer in winter and as much as 6 to 8 degrees cooler in summer, thereby reducing utility costs. The 140 square feet of plantings helps absorb air pollutants, too, and—at $13 to $45 per square foot installed—should last about twice as long as a conventional roof. For all these reasons, the Teaneck, New Jersey, couple felt good about springing for the eco-conscious home improvement. But they also value its aesthetic appeal. “The roof looks so lively and colorful,” says Sarah. “It’s definitely improved our view.”
The LiveRoof modular system they chose is typical of residential models, consisting of plastic trays filled with a soilless engineered growing medium and fully mature sedum plants that can handle both deluge and drought. At 40 pounds each, the trays are heavy and meant to be installed by a certified contractor; R&S Landscaping did the job here. See how this roof went from bare to bountiful—plus the latest on living roof DIY options.
Shown: Hardy sedums are most popular for green roofs because they thrive in a soilless growing medium and are drought tolerant. They just need a yearly trim and occasional fertilizer to look their best. Homeowners can choose from a palette of suitable plants. Sedum spurium ‘Tricolor’ is one of the most ornamental.
Prep the Roof
Photo by Alison Rosa
Even a flat roof should have some pitch so that it sheds water toward gutters; for a green-roof installation, that pitch should be at least ¼ inch per foot of run. Before the plants go up, a structural engineer should check to ensure that the roof can support the weight of the engineered growing medium and plants. When saturated, each tray in this system adds up to 30 pounds of load per square foot, which can stress a traditional roof built to support about 25 pounds. For this project, the roof was built to withstand the added load and then covered with a waterproofing membrane. Here, green-roof installer Rob Gaffney adds a second layer of rubber roofing membrane as a root barrier to prevent damage to the roof.
“Get a structural engineer to tell you what your existing roof needs to support the weight of a green roof. You might have to add more joists, strengthen existing ones, or add bracing.”
—Tom Silva, This Old House general contractor
Add Planted Trays
Photo by Alison Rosa
The 1-by-2-foot black polypropylene trays—planted four months earlier and nurtured at a nursery—arrive by truck 95 percent covered with vegetation. They come stacked in racks that are wrapped in plastic to secure them for shipping. The plastic is removed after the trays are unloaded, to keep the plants from overheating; the trays are moved by forklift (in this case) or crane to the rooftop. Before the trays can be installed, decorative L-shaped aluminum edging is temporarily weighted down around the edge of the roof where it will cover the sides of the trays. Starting in a corner and working right to left, the 40-pound planted trays are placed in rows on the roof and inside the edging. Installers start setting the trays at the lowest end of the roof, moving across and up the roof’s slope.
Connect the Trays
Photo by Alison Rosa
With a modular system like the one used here, any tray can be removed from the roof for maintenance without disturbing the others. In this system, plastic lips on the front and right sides overlap the left and back sides of neighboring trays for stability, creating a blanket that eliminates seams and reduces temperature fluctuations. Feet built into the underside of the trays keep them elevated ½ inch above the roof’s surface so that runoff can easily flow underneath toward the gutters.
Cut Trays to Fit
Photo by Alison Rosa
Usually, trays have to be cut to fit between the last full tray in a row and the edging. An installer measures for each end piece, then transfers his mark to a full tray with a wax pencil. Because the trays are filled with a growing medium made of tough aggregate, a gas-powered concrete saw fitted with a masonry blade is used to cut the trays. The cut end butts against the last full tray in the row. On this job, one installer laid the rows of trays, another took measurements for the end pieces, and a third made cuts on the ground before sending a few rows’ worth of end pieces up to the roof.
Remove Soil Elevators
Photo by Alison Rosa
Each tray arrives fitted with a 4-inch-wide band of white plastic, called a soil elevator, that allows the growing medium to rise 1 inch above the tray. Along with the curves built into the sides of each tray, the added height allows soil-to-soil contact between the trays so that water, nutrients, and beneficial organisms can move laterally among the trays. Sharing the available water reduces the chance that dry or excessively wet spots will develop. After a couple of rows of trays are in place, the installer pulls out the soil elevator at an angle to avoid removing the growing medium. This helps the roof blend together almost instantly and reduces air space between the trays, increasing the system’s insulating R-value.
Fit the Last Modules
Photo by Alison Rosa
While the planted sedums can withstand some foot traffic, the best installation pattern is one in which installers can work themselves off the roof without walking too much on the plants. Then, from a ladder, they secure the edging to the sides of the modules with exterior-grade screws.
Photo by Alison Rosa
Once the trays are installed, they are watered to settle the soil. Green roof plants like these sedums usually don’t require irrigation unless there’s a four-week spell of high heat with less than 1 inch of rainfall. During dry spells, the growing medium can shrink, leaving it vulnerable to weeds. Sarah and Scott can irrigate this roof with a self-coiling garden hose threaded into the second-floor-bathroom sink faucet. Then a yearly haircut—and occasional fertilizer as indicated by a soil test—is all that’s needed to keep the green roof fit and trim.
Case study: How to install a green roof on a private home
The site: A more than 900-square-foot expanse atop a historic building in the Prospect Lefferts Gardens neighborhood of Brooklyn. The homeowner recently re-roofed the building, in anticipation of installing a green space, she had the roofer raise the skylights several inches and bring the waterproofing material up the sides of the roof’s walls.
The plan: The homeowner envisioned a wide carpet of greenery in addition to a small space for growing some fruits and vegetables, as well as an area to hang out with friends. She hired architect and green roof pro Inger Staggs Yancey of Brooklyn Greenroof to bring her idea to life.
According to Yancey, installing a green roof is like putting together a complicated puzzle, and because of this, it’s not something you should DIY. During the initial design discussions—for this site, there were a lot—Yancey brings on a structural engineer. “The first thing you want to do is to find out how much weight the roof can support, whether it’s a lot or a little. That will change the kinds of designs you can entertain.”
The plants: The engineer’s assessment showed that the roof could hold 55 pounds per square foot—enough strength to support a full rooftop farm. “The average green roof needs a minimum of 2.5 to 3 inches of growing media,” Yancey explains. “If you’re going to grow vegetables, you need media to be 7 inches deep. But the more media you have, the more it will weigh.”
For a time, the homeowner entertained the idea of installing a full rooftop farm but eventually decided to return to her initial concept of a low-maintenance green space with a few planters for edibles. The majority of the roof would be covered with a flowering sedum.
They chose flowering sedum, a standard green roof plant, as the roof covering.
“Sedum is the standard green roof plant,” Yancey says. “It’s extremely drought tolerant, low maintenance, and never needs to be reseeded or watered. It’s a plant adapted to growing on mountaintops in low-nutrient soil. Any flowers that fall off decompose and form the fertilizer the plant needs, so it does its own little composting in a way.”
The layers: Green roofs are made of layers designed to protect the building structure from water while holding and sustaining the plants. The bottom layer is a root barrier, typically made of very thick plastic sheeting that will prevent any strong roots from digging into the building.
“Roots are drawn to carbon,” explains Yancey. “And some of the more affordable roofing materials are made primarily of carbon. It’s one of those unlucky coincidences. You have to work hard to keep them separate.”
The roof before its green makeover. All photos courtesy Brooklyn Greenroof.
Several inches of edging material—typically stones or gravel—will then be used to form a root-free border separating the growing area from any vertical elements like walls or, in this case, the sides of the skylights. Metal slats placed between the rocks and the growth media help ensure separation while retaining drainage.
Next is a moisture-retention layer that looks something like an egg-crate mattress. Enough water to sustain the plants will collect in the divots of the egg crate, while excess water can drain out through holes atop the raised bumps.
Left: Installing the root barrier. Right: Installing the egg crate-like moisture-retention layer, which was temporarily weighed down with bricks.
“One question I always get from homeowners is ‘What happens to the water when it rains? Where does the water go?’” Yancey says. “The answer is that it goes the same place it would if you didn’t have a green roof. The roof is designed so the water percolates through the green roof and can flow to the gutters and downspouts in the same pattern as a normal roof.”
Over the moisture layer goes a filter fabric specially engineered to hold in the dirt while draining out any water. There are a range of filter fabrics and growing media types, and it’s important for them to be compatible. Matching them incorrectly could result in clogged fabric or media that washes away.
Then it’s time for the growing media—a.k.a. dirt—and putting in the plants. In this case, Yancey chose pre-grown sedum that comes in large tiles.
The timeline: Once Yancey and the homeowner finalized the plans for the roof, Brooklyn Greenroof applied for a permit with the city’s Department of Buildings. In New York City, green roofs with dirt less than four inches deep do not require a permit. However, the city strongly encourages permitting for safety reasons, and the permit qualifies homeowners for a tax abatement. While most green roof permits will come through in about a month, the process took a bit longer in this particular case.
A crane hoisted the bags of growing media onto the roof.
After that, the company began ordering the necessary materials and coordinating deliveries. Installing a green roof usually takes about a week, but because of the layered nature of the installation, it’s important for materials to arrive in sequence. So planning the installation takes a significant amount of time.
“It’s kind of like putting together an intricate jigsaw,” Yancey says. “I have a system where I weigh down the first layer with the next layer in the same day, otherwise the materials or the growth media could blow away. It’s another reason why no one should DIY a green roof.”
With the help of a crane and a block-and-tackle pulley system above the roof hatch, the materials made it up onto the roof in nearly correct succession: First the rolls of root barrier, then the 1×2-meter tiles of the moisture layer and rolls of filter fabric. The final day was supposed to be laying out the growth media and large square tiles of sedum, but the rock edging and metal border arrived several days late and had to be installed the following week—after the plants were already in place.
The entire installation took about five days in total, with a weekend between planting and finally putting in the edging. The homeowner also built a set of copper-covered planter boxes to sit on the raised cornice area near the front of the building, with Wooly Pockets planted with strawberries hanging down nearby.
The money: The average cost for a bare-bones green roof—including the design, permitting, and installation—will typically run between $18 and $22 per square foot. A deeper or more specialized roof, like this one, can cost more, between $30-50 per square foot. The tax abatement for this project came out to $5.23 per square foot of green roof.
How To Make A Green Roof
A green roof is a specific type of roof arrangement over a building that is either partially or fully covered with growing medium, as well as vegetation; it is planted over a specially designed water proofing membrane that ensures protection to the tradition roof of a building.
Green roofs are constructed by merging a number of layers over a normal roof in order to create a proper root barrier, an irrigation system, as well as drainage.
In some areas green roofs are installed just to create a specialized recreation place for local communities, it also contributes to the establishment of habitats for various insects, and bees, as well as birds, as they live a difficult life in urban areas.
Analysis says that green roofs are the perfect tool for controlling undesired climate changes in cities as well as towns.
These roofs can also contribute in the prevention of localized flooding because they work effectively to reduce the intensity or volume of water by absorbing some of it and directing the remaining part over the right path.
You will be happy to hear that green roofs provide a perfect control over the heating system of buildings, as in the winter season they add warmth to rooms, whereas in the summer season they contribute in the improvement of cooling for the buildings.
If you are searching for how to build a green roof, then the following information can be very useful for you; in order to install green roofs over traditional roofs we need to make some specific arrangements and the first step is to start proper planning for execution of this task.
Although this installation task must be executed by experts only, many people prefer to follow DIY Green Roofing procedures.
For those people, here is a list of considerations that play an important role in green roofing installation:
First of all, you have to make proper measurements for the overall dimensions of your roof so that you can estimate the required amount of wood for creation of the frame. Including this, you will need a specialized pond liner that helps to cover the complete roof surface as well as small overlaps.
Note that the timber type frames, as well as growing medium contribute to some additional weight over a traditional roof; and this amount will further increase in rainy season when the green roof will absorb some quantity of water. So, in order to prevent cases of roof damage you have to make proper arrangements for strengthening of the original roof; by installing some type of support system to keep it strong under all conditions.
Here is list of some basic materials that are required for green roof installation; these items must be collected by all those who are searching hard about how to make a green roof:
- Tannalised pine wood material for a frame having the size 6 inches by 2 inches.
- Tannalised pine wood is also required for construction of internal frames: size parameters are 4 inches by 2 inches.
- You need some 5 inches’ as well as 2 inches’ screws.
- 8 *90 degree type angle brackets.
- Wood type end grain preserver.
- Garden pond liner.
- Graded soil.
Other than this, you will need some specific tools for green roof building such as a trowel for planting, buckets for lifting growing medium up to the roof, a spade for growing medium mixing, a staple gun and staples, a handheld type of electric powered drill, a paint brush, Stanley knife, a hand saw, pencil, measuring tape and ladders.
BUILDING A GREEN ROOF
Before you start with green roof building; ensure that you have collected enough information about your roof design.
First of all, you must know about the angle of roof over which you want to construct your green roof. In case this angle is more than 30 degrees, then green roofing is not preferred or you must get some advice from the experts.
Whereas for angles ranging below 2 degrees, as well as above 20 degrees, some specific design considerations are required.
One must also have a proper idea about the approximated weight of a green roof; generally, the simplest and lightest weighted green roof system will possess a total weight of about 150 Kg/m2.
Then, the next important part of green roof building is its design considerations; you have to design a strong, full frame that will surround the perimeter of the roof in order to hold all of the green roof materials.
In case the roof has an angle of more than 20 degrees, then you must ensure that it does not contribute to erosion, as well as that the plant layer will not face slipping or slumping with its weight.
All green roofs need an additional layer for waterproofing that is made up of bitumen felt or asphalt; one can make use of a heavy duty type of pond liner. Only one sheet is required so it can be fixed up with strong mastic sealant easily. A green roof generally possesses a total of five layers that include: waterproof membrane, drainage layer, filter layer, substrate as well as the planted portion.
The drainage layer is highly useful for those roofs in which the maximum angle is not more than 10 degrees. For roofs which have steeper angles, this layer is not required, as they provide natural drainage to water with an effective tilt.
This drainage layer can be constructed using some plastic material or can be designed using some course material such as expanded shade, pumice or gravel.
These layers are designed with perfect outlets so that water can find an easy path for draining.
Those who are thinking about how to build a green roof can go through the detailed information regarding the drainage process because it plays a very important role in green roofing.
After the drainage layer, we move ahead towards the installation of a Filter layer that provides effective separation between drainage, as well as the substrate layer.
The primary purpose of this layer is to provide strength to the soil by holding it tight so that soil clogging can be avoided.
In case the substrate layer is a very fine one, you must take more care towards installation of a filter layer so that it can improve the strength of your green roof.
Now the substrate depth is decided as per the type of vegetation you wish to plant over your green roof. This substrate depth is adjusted to between 20 to 100 mm in most of DIY green roof shed installation processes.
Note that soils become heavier during rainy season due to heavy water absorption; so your substrate layer must be designed with proper strength in order to avoid any damage.
Once you have installed all of these layers properly over your traditional roof, then the final task is to organize the planting process.
You can apply any method of vegetation like blankets or pre-vegetated type mats, direct on site type of planting, seeding or plug plants, etc.
For each method there are some specific advantages, as well as disadvantages that must be taken under consideration depending upon the soil type and roof strength.
Once you have finished the installation process for green roofing, now it is time to pay attention towards its maintenance so that the plants can grow properly without any trouble.
More care is required during the first year of planting. You need to add a sufficient amount of water with proper timing and use well researched fertilizers in order to improve the efficiency of the soil.
Have regular visits to your green roof and pay major attention to the removal of weeds, as well as other unwanted plants.
Experts suggest that one should avoid the use of chemicals in green roofs in order to contribute to healthy environmental conditions.
DIY green roof systems must be implemented after proper search over the type of materials and plantings that are preferred in that particular area depending upon its weather conditions.
Here are some benefits of green roofs:
We all know that flowers and plants provide a very beautiful appearance to areas and they attract many beautiful creatures like humming birds and butterflies. Green roofs contribute towards a healthy environment and provide shelter to various creatures that live in nature. With green roofs our house presents most attractive structures with ultimate natural beauty.
Green roofs act like home to various insects, small animals and birds; on the other hand, these indoor as well as outdoor plants help to cleanse air pollutants that are usually present in air due to heavy traffic on roads. Green roofs provide a major contribution towards a healthy environment.
You will be amazed to know that green roofs help to reduce the temperature of a roof by approximately 70 – 80 degrees F and that further contributes to more energy saving. These roofs provide natural warmth to a house during the winter season and keep it cool during the summer season.
If you are thinking about building a green roof on a shed, then this guide can be very helpful to you; designing a green roof over a shed will lead to a very attractive look for your house and it will contribute some positive effects to the environment.
Green roofs are the best options for urban area buildings because they provide enough energy saving ability and lead to attractive home construction.
Step-by-step directions for your DIY green roof
Professionals can examine your roof to ensure that it will be strong enough for the green roof of your choice. Whether you’re choosing to go with an extensive or intensive treatment, the primary layers of the green roof will remain the same.
The first layer should consist of a water- and root-proof membrane. A single sheet can be used to cover the whole area and keep the water and roots from reaching the roof. A heavy-duty pond liner from your local garden center can be applied with an adhesive. Make sure to mark all outlets in order to ensure proper drainage.
Cut into the containment frame, which will allow the water to run into the gutter. To keep the outlets clear, use pebbles and a layer of stones or rocks. This will avoid blockages and unwanted vegetation from gathering around the edges of the roof.
The next step is to add a substrate layer, which is usually 70 to 200 millimeters thick, but it can vary depending on the type of vegetation. By using a substrate mixture of 70-percent inorganic material and 30-percent organic material, it will be light enough, and you’ll avoid undesired vegetation growth.
The last layer is what makes your roof green. You can choose between a green roof seed mixture, plug plants, plant cuttings, or pre-vegetated green roof mats or blankets.
Create a Green Roof
By Chris Lundahl
If you take pleasure in improving your house with fun DIY projects, why not install green roof? Not only can a living roof be aesthetically pleasing, but they help protect from storm waters, provide your home with sound and heat insulation, possibly prolong the life of your roof, provide a habitat for wildlife and reduce carbon emission.
There are two types of green roofs: the intensive green roof, which requires a lot of maintenance; and the extension, which requires less maintenance.
The most typical small-scale DIY green roofs are found on sheds, vegetation on a porch roof, or the roof of a garage. If you want to reap the benefits of larger vegetation, then you can do so if the roof of your house is flat or slightly sloped. When the slope of your roof is very steep, you would need to get a professional to assist you.
Photo © Philadelphia Water Department
Green Roof Basics
The roof you are planting on should be structurally sound and strong enough, without wet areas, rotting wood or damaged materials. Waterproofing the roof is the first step, and this can be done by adding a membrane layer. Micron damp-proof liner or pond liner should cover the entire area where you wish to plant to avoid water seeping past. The only area that should be kept open and bordered to ensure no plants grow over it is the edge of the roof where the water runs down the gutter.
The next layer is a weed suppressing membrane which keeps the roots of the plants from growing through the first layer of your roof.
On a small-scale green roof, you can use old blankets as the next layer which will retain moisture, but for the roof of your home, you should opt for Geotextile membrane, which will resist fungi and bacteria.
An inch layer of gravel or limestone chips should come next to ensure proper drainage. A well-graded blend of particles with sizes ranging from 1/8 to 1/2 inch is preferred.
On top of gravel layer, you can add a layer of separation fabric or add the soil directly. Many DIY green roofs are between 3 and 8 inches (70-200 mm) deep. Some stores even provide special “green roof” soil, but you can make the mixture yourself with a ratio of 70-80 percent inorganic material and 20-30 percent of organic material. A good soil mixture should be firm and not fluffy.
Let the planting begin! Your local plant supplier can find green roof seeds, but if you do not want to wait for the seeds to grow, you can purchase pre-vegetated mats or do your planting with plants you prefer from cuttings or plug plants.
Flat vs. sloping roofs?
The easiest green roof installations are on flat roofs or those with a small slope consisting of no more than a 3-ft. rise for every 12 ft. of length. By keeping it under this, you do not even need stabilization. When you are installing a green roof on a steeper slope, you need to reinforce a system of a tray planting or create a terrace system for the soil to keep intact.
Watering your green roof during the hot season every once in a while is most of the caring that’s required. Bear in mind that extension green roofs do not need much maintenance as far as trimming goes. For whatever reason you have decided to make your green roof, just remember to have fun along the way.
Editor’s Note: Chris Lundahl is an editor covering topics on construction, sustainability and roofing. He currently works for Arizona Roofing Systems.
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A green roof is a roof which can either be partially or fully covered by plants. It generally constitutes a waterproof covering where vegetation is planted over. The green roof is different from a rooftop garden in the sense that the latter uses containers for the plants while the waterproof covering of a green roof prevents damages to the building’s structure which may be caused by water leaks. A green roof may be called by other names such as vegetated roof, living roof, or eco roof.
For people living in the urban area, green roofs are idea because it helps lower temperature and provide better insulation. Green roof also helps minimize the pollution in your area as plants absorb carbon for their food. Your green roof can also serve as storage for rainwater and provide a habitat for birds and animals.
There are two types of green roofing systems. These are based on the amount of maintenance required; amount of irrigation needed, and required depth of soil for planting. The first is intensive green roof. This type needs to use a depth which can hold large plants when they grow. Intensive green roofs require more irrigation, maintenance, power, and labor.
The other type is extensive. Minimal interaction is intended for this type of green roof. The only reason extensive green roofs are accessed is only for maintenance which takes place usually once a year. The depth of medium used for extensive green roofs are thinner as compared to intensive ones
Procedure for Building a Green Roof
The first step in constructing a green roof is acquiring the necessary building permits from the proper authorities. Check with your local municipality and even your neighborhood’s home owners association. Construction policies may differ depending on where you are located. It’s important to note that some government authorities offer incentives such as tax discounts for building green roofs.
You should have a well thought out plan for your green roof before commencing construction. It would be best to do ample research on the different designs used for green roofs. Pick the one which best suits the roof of your building. You may hire the services of a professional if you are not confident about your designing skills. Decide whether you want your green roof to be the extensive or intensive type. Make sure your roof can sustain the weight of the fixtures you need to install for your green roof.
The next important step waterproofing the roof to prevent leaks. Seal your roof with waterproof membrane to keep your building from being damaged by water. There are numerous materials you can use to waterproof your roof. A couple of the most common choices include asphalt sheeting or specialized rubber sheets specifically designed for green roofs. Make sure all the holes, cracks and edges are properly sealed when the membrane is applied.
Next is installing the root barrier. The best materials used for these are either concrete or cellular glass as they provide good insulation.
The next step is to put up the drainage layer which will lead the excess water towards the gutters to prevent water build up. Gravel and pumice is placed in the drainage layer together with high quality filter fabric such as polyester or polypropylene. This will help ease the flow of water towards the drainage layer and will keep the movement of soil or growing medium into the lower layer.
You should then put up the growing medium of about three inches in depth. Common choices include a mixture of cleansed tops soil and sand or crushed clay and humus. You may also use local soil. However, weeds may grow here and pathogens may be created.
The next thing you should build is the irrigation system of your green roof. The ideal type for start-up green roofs is the drip irrigation system. This can minimize your maintenance time and it uses up only the needed amount of water. Drip irrigation also allows you to add fertilizer easily.
The last step is to plant the seeds or add potted plants. The growth and health of your plants will depend greatly on the climate and environment of your location. This means you need to be very careful when choosing which plants to use for your green roof. Consider the weather in your area.
By following these simple steps, you can now have your very own green roof. Once you assembled your green roof, you will soon enjoy many of its benefits, including better insulation and cleaner air.
Have you ever asked yourself the question – ‘I want to build a green roof…but it all seems so complicated’? If you have, then DIY Green Roof Guide may well be ideal for you, wherever in the world you are thinking of building.
This online guide is designed to meet the needs of DIY enthusiasts looking to put a green roof on a shed or outhouse, builders and landscaper contractors who want to build green roofs.
This website based guide builds on the material and information in our original pdf – ‘The DIY Guide to Green & Living Roofs’ which we published in 2008. That original information has been taken and updated, new and redrawn diagrams made, and multi-media items added. These include short ‘to do’ videos on specific tasks. There are also publicly accessible videos on our youtube channel if you want a quick preview.
An Online Guide to Building Your Own Small Scale Green Roof
The DIY Green Roof Guide aims to take most of the mystery out of how to build a small scale green roof. Whether you want to know how to make a green roof for your shed, garage or house extension, we hope to provide a clear pathway to accomplishing it. This is in contrast to many commercial green roof product websites where the technical nature of the supplied information can easily confuse the beginner.
The first edition of the green roof guide was published in order to shed some light on this confusion. Given the large number of emails that both authors were receiving requesting help and information, it was obvious that a guide was both needed and overdue. This new web based version will take those ideas and principles forward in a form that allows information to be added and updated as necessary.
So this online guide has been created to:
- Provide members with the confidence in taking a project forward
- Set out the basic principles behind why certain things are needed (or not)
- Provide simple detailed instructions (down to what nails and screws to use) in a step by step format
- Supply construction illustrations that make the process easy.
Why an Online DIY Green Roof Guide rather than another PDF/eBook?
An online resource let’s us be more dynamic. We regularly update the material. We will add more multimedia items such as videos. When new methods are discovered we will add these to the site. It also allows us to provide relevant articles and case studies.
Occasionally there maybe confusion over terms used in the guide. Or perhaps something is not completely clear. If you are struggling with specific details and need further illumination then queries should be addressed via the Members’ Support Form and we will do our best to answer as quickly and accurately as we can.
Although we are both only English speakers we have set up mechanisms to deal with questions in other languages. If your primary language is French then a fully translated version of the guide is available at the sister website, construiresontoitvert.com.
Over the years I have refurbished several old birdhouses and I still have them in the garden. On my trip to Portland for the Garden Bloggers Fling a couple of years ago I saw a bird house that I wanted to buy. The only problem was it had plants and soil on it and I knew I couldn’t sneak it across the border to Canada. I have always wanted a green roof bird house. This week Farmer Jim decided to try making one of the birdhouses so I could have one. He is truly the best!
He has a ton of scrap lumber that he wants to use up. He had a plan to go by that he found in a garden magazine. We sat and looked at different designs online and came up with one he liked. I wasn’t sure if I liked the roof. It looks out of scale with the bottom of the house. He got busy cutting pieces for the birdhouse while I planned what would be planted on the top. Farmer Jim found an old drawer pull and fastened it to the front like a perch. I love repurposing things. The base was an addition to the original plan. It has been built so that the bird house sits on a 4″ by 4″ post. All you have to do is add an edge along the roof that is deep enough to plant. Our edge is two inches deep.
Okay, it was time to do some magic. I lined the inside of the roof with roofing paper. Farmer Jim drilled holes in each of the corners so water will drain easily. Metal flashing under the roofing paper covers the peak so our feathered friends will stay dry. We have so much rain here, drainage holes are a must. I used masking tape to hold the stiff roofing paper in place. It isn’t perfect but it will work. I think next time we will forego the roofing paper and use metal flashing on the whole inside of the roof.
Next I filled the roof with a layer of good potting soil and added some organic 4-4-4 fertilizer. I realized that once the plants go in, this two-inch layer of soil will be in place for a long time. I want the plants to flourish. I moistened the potting soil with some water.
Now it was time to add some moss to the top. I placed it carefully over the soil trying to cover every inch. The moss will keep the soil moist.
Farmer Jim attached poultry wire to the top and stapled it along the sides. He used wire with one inch openings so its easy enough to insert a plant. He watered the moss and said the drainage holes worked perfectly. Now its time to plant the roof.
I love using succulents in the garden. I was able to buy a few ‘hens and chicks’ plants from a friend. The rest of the succulents I found in the garden. I carefully poked a hole through the moss and inserted the stem of each succulent. Using a pencil or widger worked to open up a planting hole.
Succulents grow slowly so I will see how it does over the summer. Whats great is it’s so easy to propagate succulents with a bit of stem. They root very easily.
Here is the view from the top. Once the plants were in place I placed the bird house out of the hot sun. It tends to dry out the soil quickly and we want our plants to root and grow well.
Now all I have to do is wait for the plants to grow. Once I see that they are rooted the bird house will be placed on a fence post in the back garden. Did I say he has 15 more bird houses already cut and waiting to be put together? Yes, he is excited to make each bird house a bit different from each other. Its fun to use your imagination and recycle old wood to create something fun for the garden. I still think this first bird house needs a bit of colour so some painting may happen. After all we don’t want the birds to have a boring house, now do we?
For some great ideas on how to build your own green roof bird house, Check out the sites below.
Green Roof DIY Birdhouse by Birds and Blooms
Green Roof Bird House Tutorial by Garden Therapy
Rebecca’s Bird Gardens for some cool ways to decorate your new bird house. Love the creativity on these bird houses.