Buildings from waste paper

Buildings from waste paper
Claire Barlow*, Daniel Neal*, Wesley Zheng**
*University of Cambridge, Department of Engineering
**University of Cambridge, Department of Chemical Engineering
Cement making is responsible for 5% of the world’s emission of greenhouse gases: reducing the carbon footprint of
construction projects is a priority. The construction industry is looking at alternatives to cement. We are working with a
small company, Econovate, to develop a building system based on Papercrete for pre-fabricated houses.
Papercrete is made from low-grade waste paper which would otherwise go to landfill. Its carbon footprint is very low; it
provides excellent thermal insulation, and it is suitable for use in high-performance low-cost housing.
Why build more houses?
Making Papercrete panels
Waste paper is mixed with water and some
binder to provide durability, environmental
resistance, strength and integrity. We are
investigating lime and cement as binders. We
are trying to minimise the carbon footprint of
the material, so must balance intrinsic material
energies against the amount of material used.
It may be better to use stronger but more
energy-intensive materials.
The 2004 Barker Review of Housing Supply identified a severe shortfall in the number
and affordability of houses in the UK. In February 2008 the Deputy Prime Minister
announced that an additional 200,000 homes should built by 2016.
The emphasis is on affordable housing.
What are the environmental needs?
UK homes account for 27% of the total CO2 emissions of the nation.
60% of domestic energy consumption in the UK comes from space heating.
We need to build houses using low-carbon materials and construction methods.
We need to build houses which are energy efficient to run.
Papercrete panel under
construction
Why can Papercrete help?
Making the material is eco-efficient:
Papercrete has a low carbon footprint (low-energy manufacture).
It uses waste paper (reduces amount of waste going to to landfill).
Building construction methods are more eco-efficient:
Papercrete panels are being developed for use in pre-fabricated houses.
Pre-fab construction goes with less waste; fewer on-site resources.
Houses made from the material are more eco-efficient:
Papercrete has good thermal insulation properties, so less energy needed for heating.
Houses made from the material are more affordable:
Pre-fab construction methods mean houses can be build quickly and more cheaply.
Better insulation means that heating bills are reduced, so living costs fall.
Papercrete walling system
http://www.econovate.com
Testing and evaluating the material
What properties do we need?
Strength and stiffness
We must consider:
Loading from the weight of the house
Wind loading
External loading, e.g. vehicle impact, explosion, flooding
Loadings from fixings
We need to measure elastic modulus and compressive, tensile and bend strengths
Thermal properties
The material must be thermally insulating: measure the thermal conductivity
Other properties include:
Fire resistance, sound insulation, moisture barrier,stability, resistance to insects or fungi
Measuring the deflection in bending of a full-size panel
of another material, to validate the test regime. These
tests will also be performed on Papercrete panels.
What about the carbon footprint?
We need to look at the whole life-cycle of the house, balancing the
benefits which can be achieved at different stages
Making the material and building the house
Analyse the energy and resources (including water and transport) consumed in
Producing the raw materials for Papercrete
Making the material and the panels
Building the house
Energy to run the house
(heating costs)
Energy to build the
house (materials
and construction)
Running the house
Energy is needed for heating, cooling, ventilation. In the initial analysis, we look only at
temperature, using a ‘Standard house’ with our measured thermal conductivity values to
estimate annual running costs.
This stage dominates the Life Cycle Analysis of the house
End-of life
When the house is demolished, the material should ideally be re-usable or recyclable.
Analysis of this stage is future work in the project.