Monsoon Proof Roof
(Age 9–11 years)
Primary upd8 provides relevant contexts and creative hooks for your science lessons.
What’s it all about?
Practical Action supports families in local communities in Bangladesh to build flood-proof homes. Severe flooding, which is likely to continue to get worse due to climate change, has repeatedly swept their homes and, in some cases, their land away.
Villagers work together to build raised plinths on which to construct their newly designed homes. Wells have also been raised to avoid contamination.
New homes have jute panels for the walls, which are cheap to produce and resistant to the floods. They are held in place by treated bamboo poles.
This activity focuses on the final part of the house, the roof. Children will investigate whether a local material, straw, is the best material to use or if a different material would be better; something which is an issue, not just in Bangladesh.
Children will be able to work scientifically by:
planning different types of scientific enquiries to answer questions, including recognising and controlling variables where necessary.
Children will learn:
For each group items such as:
Materials to test, e.g. foil from a turkey roasting tin (as a substitute for corrugated iron), plastic as well as ‘natural’ materials such as wood
Small watering can with a rose
Tray to catch water or access to outdoor area
Paper towels to dry box between tests.
o give reasons, based on fair tests, for the particular uses of everyday materials, including metals, wood and plastic.
Introducing the activity:
Ideas for discussion starters:
What material are roofs in new buildings in your area made from?
What materials are the roofs in older buildings made from?
Is there any link with what is locally available? (e.g. stone, slate, clay tiles)
Why do modern buildings use materials bought in from elsewhere?
Why might a family change from using traditional materials for their roof to newer materials?
Use the discussion to make connections with the global issue. When selecting building materials, people must balance the suitability of the material’s properties for local conditions with availability and cost of that material. For example they may choose a locally available raw material or the material may be sourced or manufactured elsewhere and need to be purchased at greater expense.
Show slides 1 and 2 to introduce the problem.
Slide 1 introduces Mehrab, a nine-year-old boy, who lives in Bangladesh. His family is rebuilding their home on a raised area of ground to protect it from flooding.
You may like to show the opening of the Practical Action video (see websites below) from 0–33 seconds to give the children a visual idea of the conditions faced by Mehrab and his family.
Slide 2 introduces the Big question: What material do you think Mehrab should suggest his parents use for the roof of their new home? Encourage the children to look at the photograph in detail to identify problems with the straw roof (e.g. the holes) and to think about what the buildings in Mehrab’s village are used for. In Bangladesh animals are so valuable that they are often kept inside the house to keep them safe, especially when there is a risk of flooding, as houses are built on raised ground.
Use slide 3 and other images of homes around the world to encourage discussion about why different materials are chosen for roofs. Support children to distinguish reasons to do with money and availability, from scientific reasons based on the properties of the materials. In Mehrab’s village the traditional thatched roofs were made from natural resources that people could gather for free.
Ideas could include:
log cabin (roof material should help keep heat in the home, it needs to be strong to support a heavy weight of snow and waterproof when the snow melts)
conservatory (roof material to let in the sunlight but waterproof to keep out the rain).
You may wish to give the children a selection of materials and ask them to sort the materials in different ways, choosing their own criteria related to properties useful for roofs.
The children should then decide what properties are important for Mehrab’s family using the opening video clip, the weather information for Bangladesh on slide 4 and their own research. You may wish to print out slide 4 so that the children can look more closely at the data.
The children should notice that Bangladesh has particularly high rainfall for part of the year (the monsoon season). This means that roofs need to be waterproof and also strong due to the heavy rain.
Discuss with the children (using further research as necessary) what other properties would be helpful in making a good roof. Further research (see websites listed below) should show that during a monsoon the wind speed increases so roofs also have to be able to withstand strong winds. The temperatures are very hot so homes will get very hot inside. Falling rain could make a lot of noise on some types of roof.
The children should then plan and carry out one investigation to find out which material is best in terms of one particular property (encourage each group to investigate a different property). This may be used as an opportunity to provide differentiation in terms of the type of data collected. An investigation into how waterproof a material is will produce a bar chart, whereas an investigation into how the temperature inside a house varies with different materials on the roof could produce a line graph for each material. This would also provide the opportunity to use data-logging equipment.
Once the investigations are complete the children should share their conclusions.
Support the children in using their combined evidence to suggest and justify an answer to the ’Big question. It is important to emphasise that there is not a ‘right answer’. The important thing is that the children can give good reasons. To do this they will need to consider which properties are a priority for the roof to have and which properties may be desirable but not essential.
Discuss with the children the global issue that people cannot always use the best material for the purpose. A traditional material must be readily available, easy to use, and be effective such as roofing material in the local weather conditions. Other types of material also need to be readily available, easy to use and effective in the weather conditions, but they must also be affordable. There may well be advantages and disadvantages to each possible type of material.
Show slide 5: What happened next?
Mehrab’s family roofed their new house with corrugated iron. This is more waterproof than the straw and is relatively cheap to buy and readily available in Bangladesh. Mehrab’s home is now drier when it rains (although the roof is quite noisy!). The raised platform and other design features make his family feel much safer from flooding. For Mehrab’s family, keeping out the rain was much more important than whether or not the roof was noisy.
Evidence of children’s thinking and learning:
the variables that the children identify and control during the investigation
the comments the children make when discussing their results and drawing conclusions.
Extension ideas…Cross-curricular links:
This activity could be extended to consider a roof for a different part of the world, allowing the children to design investigations for a wider range of properties.
D & T
Create a model of a building with a roof of the chosen material - see Practical Action’s Beat the Flood activity. Investigate different shapes of roofs and how they are able to withstand strong winds.
Make links between local climate and traditional building styles and materials.
This activity reinforces work on means and the reading of graphs. Certain activities allow students to practice drawing line graphs, while others allow the reinforcement of drawing bar charts. The different investigations use a variety of units of measurement.
Descriptive work based on living in different types of homes or using the home as the basis for story writing.
Science at your fingertips:
All materials have specific properties. A material is chosen so that the properties of the material suit the purpose it has been chosen for. If a variety of properties are needed (e.g. strength and being waterproof) then a compromise may be needed.
Full details of Practical Action’s Beat the Flood project can be found here: http://practicalaction.org/beattheflood. Resources are freely available to use plus there are examples of pupils’ work.
The video clip may be accessed via http://practicalaction.org/beatthefloodteachers.
For weather data see:
Children can look up the current weather forecast for Bangladesh here:
Daily rainfall tables may be found by looking under ‘services’ then ‘normals’.
Health and Safety:
Please refer to the Association for Science Education publication, ‘Be Safe!’ for general advice when carrying out practical science activities.
This activity was produced by the Association for Science Education in partnership with Practical Action as part of the Global Learning Programme (GLP).
The GLP is a ground-breaking programme which is building a national network of like-minded schools, committed to equipping their students to succeed in a globalised world. The GLP helps teachers in Primary, Secondary and Special schools to deliver effective teaching and learning about international development and global issues at Key Stages 2 and 3.
ASE is providing the science education support for the Global Learning Programme which is funded by the UK government. This activity can be found on the Global Learning Programme www.glp-e.org.uk, ASE Primary upd8 www.primaryupd8.org.uk, and Practical Action Schools www.practicalaction.org/schools websites.
GLP © Crown Copyright