Low Carbon Economy, 2011, 2, 220-223
doi:10.4236/lce.2011.24027 Published Online December 2011 (http://www.SciRP.org/journal/lce)
1
Using Insulation in China’s Buildings: Potential
for Significant Energy Savings and Carbon
Emission Reductions
Guoliang Liu1, Hans Liu2
1Institute of Applied Forest Ecology, Chinese Academy of Science, Shenyang, China; 2The Biomedical Research Centre, University
of British Columbia, Vancouver, Canada.
Received September 29th, 2011; revised October 30th, 2011; accepted November 8th, 2011.
ABSTRACT
Most old residential and commercial build ings in China are not insulated or not to new standard s. This is true even in
regions with very cold winters or regions with very hot summers. The insulation in new buildings is very poor relative
to North American standar ds . However, insulating the exterior walls, attic roofs, and foundation walls to new standards
of building s in China would red uce the n eed for h eating a nd air cond itioning, and thus would save roughly 200 million
tons of coal each year. This in turn would lead to a reduction in CO2 emissions of about 510 million tons per year,
which is equal to about 8.4% of China’s total carbon emissions in 2006. The use of insulation in buildings will help
homeowners save money, help China save energy and help th e environmen t all at the same time. In sulatio n will provid e
a continued payback to the homeowner, not only in dollars and cents, but also by providing a more enjoyable and com-
fortable living environment for many years.
Keywords: China Building Insulation, Air Pollution, Energy and Coal Saving
1. Introduction
China burns about 6 million tons of coal every day [1].
According to the World Bank, of the world’s top 20 cit-
ies with the worst air, 16 are in China [1]. According to
Chinese government sources, about one-fifth of urban
Chinese breathe heavily polluted air. Many Chinese cit-
ies smell like high-sulfur coal and leaded gasoline in the
winter. Of the 340 Chinese cities that are monitored for
pollution, only one-third meet China’s own standards [1].
Coal is the number one source of air pollution in China
[1]. “The pollution is worst during the winter,” said Ji
Youping, a former coal miner who now works with a
local environmental protection agency. “Datong gets
very black. Even during the daytime, people drive with
their lights on”. Pollution is a major public health con-
cern of the government. The Asian Development Bank
says it is financing pollution control programs in Shanxi
because the number of people suffering from lung cancer
and other respiratory diseases in the province has soared
in the past 20 years [2].
China obtains 80% of its electricity and 70% of its to-
tal energy from coal, much of which is high-sulfur coal.
The sulfur dioxide produced in coal combustion poses an
immediate threat to the health of China’s citizens, and
contributes to about 400 ,000 pr emature deaths a year [2].
It also causes acid rain that poisons lakes, rivers, forests,
and crops [2]. During winter, emissions from coal-fired
central heating facilities are the primary cause of the se-
rious air pollution that is prevalent in northern China’s
cities. However, due to the major cost advantage of co al,
and to a lack of alternatives, coal is expected to remain
the dominant fuel for central heating systems in China
for the foreseeable future [3].
Officially, residential and commercial energy use ac-
count for 19% of China’s total consumption. This meas-
ure, though, omits many commercial and residential
buildings that belong to units that are categorized under
the industrial, agricultural, construction or other sectors
of the economy. Chinese academics estimate that the
buildings sector actually accounts for 23% of total en-
ergy use and will exceed 30% by 2010 [4].
Roughly half of China’s population lives in northern
regions where temperatures fall below 10˚C for more
than 90 days of the year. In terms of energy per square

Using Insulation in China’s Buildings: Potential for Significant Energy Savings and Carbon Emission Reductions 221
meter of living space, air conditioning uses more energy
in areas with hot climates, and heating uses more energy
in areas with cold climates. The total energ y required for
air conditioning and heating combined is the most per
square meter in regions with very cold winters and in
regions with very hot summers [5]. In regions with only a
moderate difference between summer and winter cli-
mates, such as in Beijing, the energy required for air
conditioning is about the same as that required for heat-
ing [5].
China currently consumes about 200 million tons of
raw coal per year for space heating of urban, residential,
and commercial buildings in its cold and severely cold
regions [5]. The amount of energy used for air condi-
tioning is estimated to be about the same as for space
heating [5], so China currently consumes about 400 mil-
lion tons of raw coal per year for the purposes of space
heating and air conditioning combined.
Energy use per unit floor area in China is at least dou-
ble that of buildings in similar cold climates in Western
Europe or North America [5], yet far lower levels of
comfort are achieved, largely because insulation is not
widely used in China’s buildings. In Canada, detailed
building codes have been in place for decades, and all
buildings in all regions are required to be insulated to a
certain standard. In Canada, fiberglass is the most com-
mon insulation material.
The cost of insulating with fiberglass is very low, ev en
when the framing lumber, vapor barrier, and drywall
components are included. The space waste associated
with the installation of insulation is very low because
only the exterior walls and roof need to be insulated. All
electrical wires, network cables, vacuum ducts, ventila-
tion ducts, and telephone lines can easily be installed
inside the wall, i.e., between the outer and inner walls,
with no need to alter the concrete walls or foundation.
The consumption of heating energy is starting to be
metered in many of China’s cities, which is causing resi-
dents to pay more attention to th eir heating bills. The use
of insulation in buildings will help homeowners save money
and help the environment all at the same time. Insulation
will provide a continued payback to the homeowner, not
only in dollars and cents, but also by providing a more en-
joyable and comfortable living environment for many years,
and by reducing greenhouse gases and air pollution.
The purpose of this paper is to discuss the effective-
ness of installing insulation in buildings in China in
terms of saving energy and in terms of reducing carbon
emissions by reducing coal consumption. We compared
the energy required to maintain the same temperature
conditions for insulated and non-insulated buildings in
China, based on the research presented in the US De-
partment of Energy’s report “Insulation Comparison De-
monstration” [6], and we calculated the energy savings
and carbon emission reductions associated with imple-
menting the use of insulation .
2. Effectiveness of Insulation
Canada’s detailed building cod es require that the exterior
walls, attic roofs, and foundation walls of buildings in all
regions be insulated to a certain standard. Fiberglass is
the most common insulation material installed inside of
concrete walls in Canada. Most old residential and com-
mercial buildings in China, even in the severe weather
regions where the winter is cold and the summer is hot,
are not insulated. The newer buildings in China are insu-
lated using Styrofoam that is in stalled outside of the con -
crete walls. Styrofoam is difficult to install, and the ef-
fectiveness of Styrofoam insulation is low, especially
after a few of years of moisture building up between the
Styrofoam and the concrete wall. Most Styrofoam is not
fire resistant, and if a fire does start in a building it fa-
cilitates the spread.
Unlike Canada and the United States, China has no
clear standards for measuring insulation effectiveness.
Every city or region of Canada has a detailed building
code that includes clear insulation standards as measured
by R-value.1 The use of insulation material and tech-
nologies has to be standardized in China in order to avoid
the mistakes associated with the application of Styrofoam.
Much can be learned from countries that have established
standards for using insulation, especially fibreglass in
buildings.
According to a report by the US Department of Energy
[3], a building with fiberglass insulation in the mild re-
gion can reduce its energy use by 50% compared with an
uninsulated building. Accordingly, China could reduce
its annual coal consumption by abou t 200 million to ns by
introducing the u se of insulation to Can adian stand ards in
buildings. A calculation th at considers the population, the
average living space per person, and the space heating
energy required per square meter [2,6] reveals that coal
consumption would be reduced by 6 million tons per year
in Harbin city alone, by 7 million tons per year in Shen-
yang city alone, and by 15 million tons per year in Bei-
jing city alone, simply by insulating buildings to Cana-
dian standards. According to the basic combustion reac-
tion, C + O2 to CO2 + H2O, an incomplete combustion
will yield CO instead of CO2. But, assuming the coal is
between 46% and 98% carbon , burning 1 ton of co al will
1R-value is a measure of thermal resistance used in the building and
construction industry. Under uniform conditions it is the ratio of the
temperature difference across an insulator and the heat flow per unit
area. The typical per-inch R-values for building insulation materials are
R40 for vacuum-insulated panels, R3.7 for fiberglass, R2.5 for wood
p
anels, and R0.08 for poured concrete. i.e., 1 inch of fiberglass insula-
tion is as effective as 46 inches (3.7/0.08 = 46) of poured concrete [6].

Using Insulation in China’s Buildings: Potential for Significant Energy Savings and Carbon Emission Reductions
222
generate 1543 to 3560 k g of CO 2. On average, a 200 mil-
lion ton reductio n in coal for the purposes of heating and
air conditioning for the whole of China will mean an
overall reduction of 510 million tons of CO2 emissions
each year.
Implementing the use of insulation to Canadian stan-
dards in China’s buildings would reduce annual CO2
emissions by 15 million tons in Harbin alone, by 18 mil-
lion tons in Shenyang alone, and by 38 million tons in
Beijing alone. China’s population in 2009 was 1300 mil-
lion [7], and its per-capita carbon dioxide emissions were
4.65 tons [1], for a total of 6045 million tons of CO2 emi-
ssions per year. Therefore, a 510 million ton reduction
per year in CO2 emissions as a result of reducing the
need for heating and cooling would be equal to about
8.5% of China’s 2006 total CO2 emissions (510/6045 =
8.5%).
As per the results of the US Department of Energy’s
study (Table 1) [6], and based on China’s housing de-
velopment from 2008 to 2010 [7], theoretically China
could reduce its annual coal consumption for the pur-
poses of heating and cooling from the current 400 million
tons per year to 200 million tons per year by introducing
the use of insulation in bu ildings.
The installation of insu lation in b uild ings req uires only
a one-time invest ment on the part of the builder or own er,
yet the positive effects on the environment are long term.
A one-time insulation investment will provide a 50-year
payback. China would save a total of 10,000 million tons
of coal during the next 50 years if Canadian standard
insulation was introduced to China’s buildings today (50
years  200 million tons per year). At the same time, 25
500 million tons of reduced CO2 emissions would be
achieved (50 years  510 millions tons of CO2 emissions
per year). These achievements would make significant
inroads in managing China’s energy supply and air pol-
lution problems, and in providing comfortable living
space to the people in China. Also, because of the effec-
tiveness of insulation, the use of other heating options,
such as electricity or solar energy, become possible.
Table 1. Energy consumed to heat or cool a fiberglass-in-
sulated building and an uninsulated building, for one week
of each season.
Season
Building type Autumn
(kW) Winter (kW) Spring (kW) Summer (kW)
Fiberglass-insulated 90 350 48 100
Uninsulated 159 685 100 210
From “Insulation Comparison Demonstration” report by B. Justice, Louisi-
ana Department of Natural Res ou r ces [6].
3. Conclusions
Fiberglass is a common insulation material in Canada
and the United States because of its effectiveness, low
cost, and user friendliness. A 1-inch thickness of fiber-
glass (R-value 3.7) is as effective an insulator as a 46-
inch-thick concrete wall. Good insulation not only helps
create comfortable living spaces but it also reduces the
need to use air conditioning and heating, which in turn
significantly reduces greenhouse gas emissions and air
pollution because there is less need to burn coal.
It is important for China to spend more effort on re-
searching and promoting the use of energy-efficient
technology and equ ipment, but it is also important to pay
more attention to the benefits of insulating buildings.
Insulating existing buildings to the proper standard is a
very cost-effective method of saving energy. China can
reduce its coal consumption by about 200 million tons
each year by introducing the use of fibreglass insulation
to urban residential and commercial buildings in regions
with severe climates. The CO2 emissions can be reduced
by 510 million tons each year, which is about 8.5% of
China’s 2006 total carbon emissions.
Although the installation of insulation in buildings re-
quires only a one-time investment on the part of the
builder or owner, the positive effects on the env ironment
and the payback are long term. If the broad use of insula-
tion in buildings was introduced today, over the next 50
years China would save a total of 10,000 million tons of
coal and reduce CO2 emissions by 25,500 million tons.
Our conclusion is conservative comparing with Dena’s
report “by applying new standards, the country could cut
energy consumption for new buildings by up to 80 per-
cent” [8] because we did not include other factors. Our
analysis result is similar to Lei’s research “Comparison
of Building Codes and Insulation in China and Iceland”
[9].
REFERENCES
[1] World Bank Group, “World Development Indicators,
Carbon Dioxide Emissions in Metric Tons per Capita,
China,” 2010.
http://www.google.com/publicdata?ds=wb-wdi&met=en_
atm_co2e_pc&idim=country:CHN&dl=en&hl=en&q=car
bon+emissions+china
[2] G. Feller, “China’s Coal, the Reality of Energy Develop-
ment in China,” 2010.
http://www.ecoworld.com/energy-fuels/chinas-coal.html
[3] K. Bradsher and D. Barboza, “The Energy Challenge:
Pollution from Chinese Coal Casts a Global Shadow,”
2011.
http://www.nytimes.com/2006/06/11/business/worldbusin
ess/11chinacoal.html
[4] D. G. Fridley, N. T. Aden and N. Zhou, “China’s Build-

Using Insulation in China’s Buildings: Potential for Significant Energy Savings and Carbon Emission Reductions
223
ing Energy Use Lawrence Berkeley National Laboratory
Report (LBNL-506E),” 2011.
http://china.lbl.gov/publications/chinas-building-energy-u
se
[5] EcoWorld, “Air Pollution,” 2010.
http://www.ecoworld.com/pollution/air- pollution
[6] B. Justice, J. C. Caldwell, T. M. French and P. Ridgeway,
“Insulation Comparison Demons tration,” 2011 .
http://dnr.louisiana.gov/assets/docs/energy/programs/reside
ntial/Zoo_Project_ Final_Report.pdf
[7] World Bank Group, “Population 2009: World Develop-
ment Indicators,” 2010.
http://siteresources.worldbank.org/DATASTATISTICS/R
esources/POP.pdf
[8] S. Kohler, “By Applying New Standards, the Country
Could Cut Energy Consumption for New Buildings by up
to 80 Percent,” 2011.
http://www.dena.de/en/services/dena-newsletter/current-is
sue/guideli nevalues-for-chinas-building-boom/
[9] H. Lei and P. Valdimarsson, “Comparison of Building
Codes and Insulation in China and Iceland,” Proceedings
of World Geothermal Congress 2010, Bali, 25-29 April
2010.