With more and more engaged homeowners embracing sustainability, environmentally friendly properties and a lower carbon footprint, sedum roof construction solutions have skyrocketed in popularity.

And if that includes you – and you’d like to know what all the rage is about – you’ve come to the right place!

At Roofing Superstore, we took a deep dive into the latest green roof trends to put together this comprehensive guide.

We’ll cover everything from sedum flat roof costs to maintenance tips to green roof benefits.

Let’s crack on.


Table of contents:


What is a sedum roof?

Sky Garden sedum roof construction system

First things first – let’s make sure we’re all on the same page.

Rooftop sedum is the name for the plants and wildlife you can install on top of your roof. Sedum is the name of the living elements, but this type of roofing system is commonly known as a green roof.

Green roofs refer to a roof made up of a blanket of rooftop sedum which grows and flourishes to provide a real and natural habitat for plants, animals and wildlife. These bio-diverse rooftop installations offer a home to wildlife and a good-looking, natural view for those lucky enough to be in office space or residences that overlook these.

Now:

Wallbarn and Sky Garden are two big manufacturers of rooftop sedum systems. Wallbarn’s system is modular, so you purchase certain-sized sedum roof trays and all the smaller pieces you need to make up an entire interlocking system of a sedum roof.

On the other hand, Sky Garden comes as a blanket system in full kits in a selection of area sizes. In many cases, manufacturers offer pre-grown sedum that’s ready to go. So, when it’s installed, you don’t have to wait for any foliage to grow – you get an instant green roof!


Can you install rooftop sedum on any roof?

You can install a sedum rooftop green roof on any roof pitch from entirely flat to entirely vertical. Of course, with vertical green ‘roofs’ climbing up walls, you must be sure it’s fixed into place and consider that sedum plants and flowers will shed leaves and petals.

The good news is:

Green roofs aren’t just for commercial buildings like schools and offices. In fact, many domestic residence owners are choosing green roofs to improve their quality of life and bring some of nature closer to their homes. An eco-home, if you will. Private projects are becoming more and more common as the benefits of green roofs become more apparent and cities become denser.

Roofs that are going to have any kind of rooftop green roof system installed on them should be waterproofed already, but it’s always worth inspecting this as part of maintenance before green roof construction. You’ll only have to take it up again otherwise! A rooftop sedum system contributes to the life of a roof as the sedum soaks up water and uses it to survive.

It’s advisable that if your building is older, or perhaps other structural work has been carried out like adding a roof light or lantern, you get a structural survey. This is down to the fact that installing a green roof will add weight to the roof.

How much weight, I hear you ask?

It’s usually around 100kg per m² so it’s prudent to tell an expert what your plan is so there’s no trouble further down the line.

To find out more about installing a green roof, check out our case study!


Does a green roof require maintenance?

Wallbarn M-Tray modular green roof system

 

Sedum is drought-resistant vegetation, so you don’t need to water it. There is some regular maintenance that would apply to any roof, though. This includes inspecting and cleaning gutters, as well as some maintenance that wouldn’t apply to standard roofs!

For example, it’s advised that occasional weeding is undertaken to get rid of any unwanted species that disperse and seed themselves.

It’s advised that within the first few months of an installation of a sedum roof, it’s saturated every day. You can do this manually if you have access to the green roof, but it’s most commonly undertaken using an irrigation system.


Can you walk on a sedum roof?

You can walk on a sedum roof for maintenance on occasion and do less common tasks like retrieving something dropped out of a window, but it’s generally not advised that you walk on a sedum roof often. Green roof systems are designed to flourish their own eco-system and habitat. So humans walking across this will disturb it, squash plants and scare off wildlife.

What’s more:

The roof it’s installed on may be safe for the load of the green roof and a few people, but as a thoroughfare or an area for staff members to sit and eat lunch, it’s not safe.


How much does a sedum roof cost?

Sedum roofs are priced per m² as all roofs are. So, this is dependent on which manufacturer you want to go with for your sedum roof construction and whether you pay for regular maintenance for the aforementioned items. Installation by a professional is a must for a sedum roof. Recent health and safety legislation has also stated that at least two people must be present during the installation regardless of size.

And that’s not all:

Other variable factors include if you need to install an irrigation system because you don’t have access to the roof to water when it’s first installed or if you have a lot of detailing in the roof like parapets and chimney stacks. You will also need to consider whether you want the sedum pre-grown or not.

Keep in mind that if you want sedum already grown so the green roof is truly ‘green’ when installed, this will cost more per m² than if you opt for a system where the sedum is planted, but not flowered yet.

Below is a table to give the cost of a SkyGarden green roof system kit that contains the surface finish, the substrate, the filter fleece, the drainage and retention layer and the protection fleece.

Green roof size and typeEstimated cost
50m2 Kit (no pre-grown wildlife)£2,409.42 ex VAT
50m2 Kit (pre-grown wildflower)£2,700.59 ex VAT
100m2 Kit (no pre-grown wildlife)£3,791.80 ex VAT
100m2 Kit (pre-grown wildflower)£4,417.65 ex VAT

Green roof benefits

Wallbarn flowers

As we mentioned earlier, a green roof comes with plenty of benefits. Let’s take a closer look at the main ones.

Improves roof drainage and recycles rainwater

Classic drains are ideal for controlling where the water goes. As a result of this, however, a grand amount of water is traditionally filtered into built-up locations. A green roof is an ideal alternative as the plants can soak up the water it needs before letting it naturally run its course.

Improves energy efficiency by insulating roofs

It should be no surprise that plant-based systems are much more efficient for the environment. By choosing to apply a green roof to your property, you’re also saving costs on your air conditioning and heating bills – which leads to the next point!

Reduces the effect of UV rays on the roof, increasing life span

Traditional insulation has its benefits, but unfortunately, some issues can cause discomfort with the insulation. This can be anything from heating issues in colder climates to overheating issues in warmer climates. Using a sedum green roof means having more suitable heating in those specific temperatures. Especially in the sunnier periods as plants can soak up the UV rays from the sun.

Likewise, because of the green roof’s natural ability to deal with certain weather conditions, the sedum roof can help extend the life of the membrane beneath it.

Improves air and water quality in the area

According to National Statistics, buildings fell just behind transport as the main providers of CO² emissions in 2018. So sedum roofs are a fantastic alternative! Allowing for cleaner air to exist in built-up spaces and thus reducing the effects on the population and nature.

Reduces noise transfer by up to 8 decibelsInstalling Wallbarn roof sedum

Noisy neighbours, vehicles and other various repetitive sounds can be a nightmare to deal with. Due to the depth of your sedum roof construction, your sedum flat roof can help reduce the noise from outside sources.

Adds more green space to dense, concrete cities

Overall, the visual aspect is the first and most notable thing you might be aware of when you’ve applied your new green roofing. Many areas today lack in having that natural, eco-friendly atmosphere. So adding this type of roofing will be the way you can show your appreciation for the environment.


For more information on green roofs and their benefit, contact our customer service advisers on 01752 692 760 or use the live chat to speak with us at your convenience. 

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