More and more of us are ditching the commute and working from home. Insulated garden offices make ideal all year round workspaces. In this article we’re looking at how a living green roof can help insulate against heat and cold.
Garden offices, summer houses and sheds are a real asset to many of us, yet it can be difficult to regulate the temperature within them. A living green roof carries many benefits and is well worth considering.
- Creates a layer of insulation where heat is most likely to be gained or lost – ie the roof
- Helps reduce rainwater runoff saving £££’s on guttering and drainage systems
- Insulates against noise
- Is beautiful to look at from an upstairs window
- Attracts and supports a wide variety of wildlife
- Helps to improve air quality
- Great PR for businesses – a living roof truly demonstrates your environmental ethics
Let’s look first at insulation
Insulated garden offices are cooler in summer
We tend to associate insulation with energy conservation in winter time. However anyone who has tried to work in a hot stuffy office will know that summer cooling is important too. An air conditioner is expensive to run, harmful to the environment and sometimes distractingly noisy. So before you invest in an electricity eating machine, why not consider a living roof.
What colour is roofing felt? Yup. Usually black or dark green. And what colour absorbs heat from the sun? Right again – the same colour as your waterproofing. So the first thing a living roof will do is reduce the amount of heat that your building absorbs.
A living green roof works in two ways to keep your garden building cool in summer.
- Adds a layer of insulating soil and plants to stop the sun beating down directly on the roof
- Wicks heat away through the combined processes of evaporation and transpiration*
Transpiration is how plants keep themselves cool – they release water vapour from tiny holes in their leaves. This is the process that makes a lawn cool to sit on while patios and pavers are scorching hot.
Green roofs to keep your garden building cosy inside
Insulating a building to preserve heat is nothing new to UK householders. We’re all very accustomed to loft insulation and green roofing works in much the same way – except it’s outside of the building.
Unlike “dry” internal insulating materials, the behaviour of a living green roof changes constantly according to the weather. You won’t be able to find or calculate a “U” value, but search online and you’ll find lots of research to support the insulating properties of green roofs.
Two types of living green roof for insulated garden offices
Sedum green roof
Our favourite green roof for a smaller building. Installing the Enviromat green roof buildup is simple. Plus because it weighs less, there’ll be less strain on the building. You can find out more about sedum green roof here.
Wildflower green roof
By far the best insulator, wildflower green roofs need at least 150mm of growing medium to root into. They’re like a thick snuggly blanket on top of the building and will keep you cooler in summer and warmer in winter. A word of caution here though – be sure that the roof can carry all that weight. You can find out more about how to lay wildflower turf here. If in doubt, consult a structural engineer.