Considering a Green Roof System? But not sure whether to install a sedum or wildflower system?

It is a common question for anyone investigating green roof systems. Both types of green roof have pros and cons…so which one should you choose?

Many factors should be considered when installing a green roof system –

Maintenance

Both sedum and wildflower (Bio diverse) roofs require maintenance. However a wildflower roof will require much more maintenance due to their large variety of plants and the types of plants used. Whereas sedum are very low maintenance and rather hardy. Wildlfower roofs require more feeding, irregation and are more labour intensive.

Appearance

Sedum is a hard wearing and draught tolerant plant which offers colour all year round. Sedum is aesthetically pleasing, as is wildlfower roofs. Wildlfower roofs offer a more varied mix of plant species and local wildflower plants can be incorporated into a wildlfower green roof to enkeep with the surroundings.

Weight

Wildflower roofs require a deeper substrate to hold more nutrients. Whereas sedum is very versatile in extreme weathers and can survive easier in shallow substrate. Therefore when installing a wildflower roof , the roof weight limit must be considered to make sure the roof will uphold the system

when fully saturated.  A green roof with a weight of 30kilo per m2 generally consists of just sedum whilst a wildflower / bio diverse roof can weigh upto 220 kilo per m2.

Wildlife and habitats

Both sedum and wildflower roofs provide much need habitats and food sources for wildlife and insects. However wildflower roofs can attract a wider variety of wildlife including bees.

The most popular questions asked…..how much does a green roof cost?

Well unfortunatley there isn’t an excat answer to this question. Why? Because there are many differnent options when installing a green roof system. Each one altering the finished cost.

The cost varibles for a green roof are:

• Intensive green roof or an extensive green roof? An intensive green roof is alot heavier, consisting of much more vegetation and substrate. Therefore an intensive green roof is more costly than an extensive green roof.
• Which plant system you would like to use. Sedum roofs are very popular but some people opt for the wildflower biodiverse option. Wildflower roofs are more expensive than sedum roofs due to the range of plants.
• Will you be installing it yourself or hiring a contractor and architect to design and install your green roof? Doing it yourself can save you a lot of money but you will need to understand the roof requirments to ensure your roof can support the system and how to install in correctly.
• Green roof accessories….Will you require edge retention trims or a pebble border? All these come at an extra cost.

As an estimate in the UK the average cost per square meter of extensive green roof system is £50-100, whereas an intensive green roof system is £60-150. Finally there is also ongoing costs to consider for maintenance and repairs. Even though green roofs are low maintenance they still need some care and attention once a year to continue preforming at their best.

With all that said , a green roof system is very cost effective compared to traditional roofing solutions. It offers many benefits to both the environment and living costs such as heating bills.

Understanding Heat Islands – Why Green Roofs can cool us down!

What is a heat island?

The heat island effect – The term ‘Heat Island’ describes built up areas (urban) where temperatures are much higher than its surrounding rural areas. Everyone has experienced this, even in a small scale. The feeling when you walk from a built up areas into a park or open space with trees and plants, you instantly feel cooler. You are experiencing the effects of the Heat Island Effect.

The Heat Island effect is created due to large populations, the increased amount of buildings, cars, industrial sites and polution.