There's no doubting the beauty and power of bamboo as a building material, is there? But just how feasible is building with bamboo in the UK and Ireland?
Splendour in the grass
When you first begin planning a selfbuild and are considering potential building materials, the chances are that you'll immediately focus on the most commonly utilised and widely accepted materials used today: wood, stone and concrete.
There's no doubt, however, that when it comes to aesthetics in building, you would have to go a long way to beat the style and beauty of bamboo. Once associated with tropical huts, bamboo is now being used around the world to build everything from luxury homes and holiday resorts, to churches and bridges.
One fabulous example is Green Village resort in Bali - a gorgeous collection of individually-styled bamboo houses! When you look at the pictures of these exclusive homes, it's difficult to not be carried away by the thought of creating a similar type of dwelling at home and, in fact, architects around the world are increasingly becoming interested in - and excited about - working with this alternative building material.
But what exactly is bamboo - and can it ever provide a viable option for construction in the UK and Ireland?
Background to bamboo
Bamboo is actually a wild grass, which grows on otherwise unproductive land such as deep ravines and mountain sides in primarily tropical regions of the world. Widely used in Asia, the Pacific Islands and Central and Southern America, it is a sustainable and sturdy building material, which holds a number of advantages over other construction materials.
One of bamboo's main advantages as a construction material is that it grows extremely quickly - the fastest growth rate can reach 100cm in a 24-hour period - and its regeneration rate far surpasses that of wood. Where trees require 25 to 50 years to regenerate, bamboo has the potential to be harvested every three to six years.
Each of bamboo's 1450 species - of which only around seven are suitable for construction - comes with its own structural properties. While some are hollow, for example, others are solid. Similarly, while some will only grow to around seven inches, others will reach heights of 130ft!
As a building material, bamboo is extremely strong. It has the tensile strength of steel, the compressive strength of concrete, and one pole can hold up to four tonnes. Yet, while it's considered to be heartier than oak, bamboo is also flexible and lightweight, and so can be easily cut and repositioned with no need for sophisticated equipment.
Bamboo also wins in the 'environmentally friendly' category since it is CO2 neutral: a fact confirmed in December of last year by a new report released at the COP21 Paris Climate Conference.
The report: 'Environmental Impact of Industrial Bamboo Products: Lifecycle Assessment and Carbon Sequestration' used a Lifecycle and Carbon Footprint Analysis, to evaluate bamboo flooring, decking, cladding, panels and beams, and the results clearly highlighted that the products had a carbon-neutral footprint.
Building with bamboo in Europe
While bamboo construction is on the increase around the world, in the UK and Ireland it is still used primarily for aesthetic and decorative purposes. Many people mistakenly believe that bamboo construction is not feasible in the UK and Ireland due to the climate, but it is in fact not permitted because, at present, Europe does not have approved building regulations for permanent bamboo structures.
Bamboo is certainly easily obtainable throughout Ireland and the UK through the increasing number of companies which readily supply the material, but the bamboo, which is imported, is treated and engineered, ie, it has been converted to a product that has been tested and which meets certain specifications.
It is this process which renders building or construction with bamboo impossible at this time in this region: the engineered material is not load-bearing and, while it's certainly versatile for interior and exterior use, poles that would be the correct length for construction purposes are not available and the engineered version doesn't meet EU load-bearing specifications.
Fortunately, the engineered bamboo which is readily available throughout NI and ROI, does meet EU specifications and so it's easier for architects and designers to both obtain and work with. As a result, the last few years have seen an increase in how bamboo is used in homes throughout Ireland.
Externally, the grass is used for a variety of tasks: guttering on sheds, coverings for wall areas, screening for walls that can't be raised any higher, decking, façade cladding, water features, bin shelters, oil tanks and outdoor barbeques.
Internally, bamboo can be used for any job where hard wood would normally be utilised, such as doors, ceilings, wall coverings, staircases, kitchen worktops and wardrobes.
The fact that bamboo always has to be imported to the UK and Ireland obviously creates certain problems.
For a start, unlike its native habitat, where it is easily procured and comes with a low price tag, the import process can obviously make bamboo less cost effective, but it can also impact on the material itself during the treatment process.
Bamboo stems are ready for harvest after four to five years: an extremely fast time compared to tropical hardwoods and one of the main reasons why the material is ecologically viable.
Once harvested, the poles are stored horizontally and supported to prevent sagging or bending. Good air circulation is vital, so they are stored in a dry, shaded and well-cooled area about 50cm above ground level. At this point they also have to be treated to protect the canes against insects.
Once the bamboo has been harvested, the stems are split length wise to strips and the outer skin is removed. (The natural colour of the strips is light yellow but they can be steamed in order to give them a light brown or dark brown colour.)
When it's harvested for use in its native territory, bamboo is worked with while it is fresh, with workers employing both their hands and machetes to cut it. while fresh, it is full of moisture and, as such, is easy to cut.
When it's being prepared for export, however, the bamboo is packed away wet. During export, it dries out and, once it has undergone this drying process, is no longer easily bent, making it difficult to work with. Also, since it is packed away wet, once opened, it tends to be covered in mould.
(Despite its strength, as a plant, bamboo is still susceptible to deterioration agents, such as rot, insects, fungi and fire, so it's vital that it's treated every few years. If left untreated, it will only have a natural durability of less than two years.)
The future for bamboo
Despite the limitations, interest in bamboo continues to grow. This highly-sustainable and beautiful material is extremely versatile and, if protective measures are employed, it can last for many years.
While it is increasingly used externally and internally in homes across Ireland and the UK for its aesthetic appeal, all hope is not lost just yet for bamboo construction in the future. In fact, a team of British researchers from the University of Bath, Coventry University and the University of Cambridge is currently exploring the use of bamboo for the widespread construction of homes. The research team is currently working to develop an understanding of the anatomy and structural applications of bamboo in the hope of modifying it to overcome these limitations, while still maintaining its unique mechanical properties.
Ironically, however, the popularity of bamboo may actually eliminate the endemic species. At present, there is no management of bamboo plantations that has been developed on a scale that is sufficient enough to support adequate supply to industry or households. If that happens, bamboo will face the same supply crisis as wood, which would mean a very ironic end to the material of the future!
(This article first appeared in Selfbuild magazine in 2017).