Bamboo International Standards

I remember clearly as a young graduate architect in England and trying to decipher my first British Standard as a newbie designing steel frame buildings! Woah! It was definitely difficult and it was, as they say, as ‘clear as mud’ then.

Timber, steel and concrete are materials that have between them hundreds if not thousands of standards and codes referencing their use and application, based on decades of being tested, developed, standardized and applied.

Time wise, it took over 30 years for a ‘new’ material like carbon fibre to be recognized and ‘standardised’. How about bamboo, a material that is now re-emerging? It can be a struggle for an architect starting out in bamboo to navigate this topic.  Here are some notes that may make the mud a bit clearer.

1. What are the current international standards that exist for bamboo? 

 The International Organization for Standardization (ISO) published three standards in 2004 on bamboo construction. These standards reference existing ISO timber standards with the testing methods adapted to bamboo. 

Standard 1 

ISO 22156: Bamboo – structural design provides basic design guidance for full culm construction. A new standard is due 2022.

Standard 2

ISO 22157-1 Bamboo – determination of physical and mechanical properties – part 1: requirements which specifies test methods. Revised 2019.

Standard 3

ISO 22157-2 a laboratory manual for determining material properties. Revised 2019.

A new standard ISO 19624 was published in 2018 and it deals with the structural grading of bamboo culms for construction. It details the grading procedures for visually and mechanically sorting bamboo poles for structural applications. These procedures can be used as part of official grading systems, to ensure the safety and quality of bamboo structures.

You can find out more or purchase the above standards here if so needed – https://www.iso.org/store.html

2. What is the difference between a code and a standard?

Google search does it well this time –

‘Codes can be approved by local, state or federal governments and can carry the force of law. The main purpose of codes is to protect the public by setting up the minimum acceptable level of safety for buildings, products and processes. A technical standard is an established norm or requirement.

A code can include references to standards, which means the standards are incorporated by reference and therefore are part of the code and legally enforceable’

3. What organizations spearhead and develop these standards?

International Organization for Standardization (ISO) and International Bamboo and Rattan Organisation (INBAR). The ISO/INBAR Taskforce is fundamental in coordinating and formulating the bamboo standards. Keep in touch with developments by following their websites  (links above).

4. Which countries have formed/adopted/developed their own bamboo standards and how do these standards relate? 

Here is a list of countries with bamboo codes/standards:

a. China

b. Columbia

c. Ecuador

d. India

e. Peru

f. Bangladesh

g. USA

h. Philippines

The following are the further details of each country’s code/standards (Extracts from Engineering Sustainability, Volume 167 Issue ES5 ) :

a. China

G/T 199: Testing method for physical and mechanical properties of bamboo used in building (PRC MoC, 2007)


Standards on full culm bamboo, such as JG/T 199: Testing method for physical and mechanical properties of bamboo used in building (PRC MoC, 2007), provide guidance for material and mechanical testing.

 b. Columbia

The first country to produce a country specific code. The Colombian code for seismic-resistant structures includes a chapter on structures built with the most common bamboo species in Colombia, Guadua (Guadua angustifolia Kunth) (ICONTEC, 2010). 

additional Colombian standards are NTC 5407, on structural joints with Guadua angustifolia Kunth (ICONTEC, 2006), and NTC 5525, which concerns methods and tests to determine the physical and mechanical properties of Guadua angustifolia Kunth (ICONTEC, 2007). 

Code - Reglamento Colombiano de Construccio ́ n Sismoresistente 

c. Ecuador

Code - Norma Ecuatoriana de la Construccio ́ n – chapter 17 Utilizacio ́ n de la Guadua Angustifolia Kunth en la Construccio ́ n (Use of Guadua angustifolia Kunth in construction) (INEN, 2011) 

d. India

National Building Code of India, section 3 Timber and bamboo: 3B (BIS, 2010) 

Standard - S 6874: Method of tests for round bamboos (BIS, 2008)
IS 15912: Structural design using bamboo – code of practice (BIS, 2012) 

 e. Peru 

Reglamento Nacional de Edificaciones, Section III. Code E100 – Disen ̃ o y Construccio ́ n con Bamboo (ICG 2012) 

f. Bangladesh  

National Building Code – Chapter 4: Bamboo. 

g. USA

ASTM D5456: Standard specification for evaluation of structural composite lumber products (ASTM, 2013)
 

h.  Philippines

h1. PNS ISO 19624:2020 Bamboo structures – Grading of bamboo culms – Basic principles and procedures. This standard specifies the grading procedures required to achieve the degree of reliability intended for the structural application of bamboo culms
h2. PNS ISO 22157:2020 Bamboo structures – Determination of physical and mechanical properties of bamboo culms – Test methods. This standard specifies the test procedures for specimens obtained from round bamboo culms. 

For those that may want more on this a useful commentary of how the bamboo standards evolved can be found in David Trujillo’s presentation, ‘Developments in Structural Design with Bamboo’.  A other reference on this would be the paper ‘Sustainable structures -  Bamboo Standards and Codes’.

5. What are the new standards being drawn up and how will they affect the bamboo industry?

a. a standard focusing on glued laminated bamboo and parallel strand bamboo products.

b. a technical specification which provides guidelines on the design of bamboo structures. 

 The rise of engineered bamboo is significant and the products that are being produced are similar to timber ie. laminated columns and beams, planks and flooring .

It is notable that there has been a shift towards using timber-based testing methods for engineered bamboo products. This will provide a comparison to other timber products and broaden the potential markets for structural and engineered bamboo products. It will also open up the market for architects to specify bamboo for their work.

6. For countries currently without their own bamboo codes/standards, how can we begin to convince approving authorities with some of these codes/standards so that they can use them as a basis to approve our bamboo design work for construction?

For me, when working with full culm bamboo in these countries, one of the methods is to reference the already existing international standards and if relevant to also use standards of neighbouring countries or countries with similar bamboo species.  

As an example from a project, our structural engineers used the following basis for their analysis of our bamboo building design:

1.  Ilmu Konstruksi Bangunan Bambu / Heinz Frick. (I am trying to get a copy of this one)

2. ISO 22156 / Bambou – Structural Design, International Organization for Standardization (ISO) (2004)

3. ISO 22157 / Bambou – Determination of Physical and Mechanical Properties, International Organizationfor Standardization (ISO) (2005).

4. Structural Use of Bamboo. Part 2 : Durability and preservation, The Structural Engineer, 94(8), pp.40-43

5. Structural Use of Bamboo. Part 3 : Design values, The Structural Engineer, 94(10), pp.38-45

6. For this project, we use dry (12% moisture content), mature (3-5 years) bamboo that is free of visual defects (splits, decay, etc.),

In addition to referencing of standards that we design and construct to, we also use examples of similarly built and tested bamboo work as precedent to engage with the approving officials.

As surely as the sun rises every morning, so will bamboo rise - Ewe Jin Low .