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					  International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN
     INTERNATIONAL JOURNAL OF CIVIL ENGINEERING AND
  0976 – 6316(Online) Volume 5, Issue 1, January (2014), © IAEME
                                   TECHNOLOGY (IJCIET)

ISSN 0976 – 6308 (Print)
ISSN 0976 – 6316(Online)                                                             IJCIET
Volume 5, Issue 1, January (2014), pp. 66-72
© IAEME: www.iaeme.com/ijciet.asp
Journal Impact Factor (2013): 5.3277 (Calculated by GISI)                          ©IAEME
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    FEASIBILITY OF USING INSULATED CONCRETE FORMS IN HOT AND
                           HUMID CLIMATE

                    1                   2                                   3
                        Selvapandian,       Professor. K.P. Ramachandran,       Dr. Neeraja
                         1
                       Caledonian College of Engineering, Muscat, Sultanate of Oman
      2
          Associate Dean (Research), Caledonian College of Engineering, Muscat, Sultanate of Oman
                      3
                       Associate Professor, VIT University, Vellore, Tamilnadu, India



  ABSTRACT

          Insulated concrete forms are used widely in cold climates to control heat loss from inside to
  outside from the living areas of the building. Even though, oil is the major source of power
  generation in Middle East Countries, there is huge potential to use electrical energy more efficiently
  in buildings by applying thermal insulation. In this paper, an attempt has been made to compare the
  hygric behavior of a building with ICF construction and a building with normal concrete construction
  in Muscat, Sultanate of Oman. Hygrothermal performances of the walls were studied on these
  buildings during the peak summer months of July, August and September 2013. The result indicates
  that the performances of insulated concrete forms are comparatively better than the normal concrete
  block walls.

  Key words: Hot and Humid Climate, ICF, Thermal Performance, Insulation, EPS.

  1. INTRODUCTION

         Oman is a country which has a long span of summer with dry, hot and humid climate. The
  summer season of Oman records high humidity condition (up to 80% RH and up to 48º C
  sometimes) and this is not suitable for the living conditions. Maximum energy is used on the
  operation of air conditioners to maintain the thermal comfort inside the buildings. Electricity
  generation is by using petroleum oil, which is the major natural resource of Oman. Energy
  conservation and the use of thermal insulation for walls and ceilings are an emerging practice in
  Oman. Thermal and hygric behavior of buildings are related to each other. Increased humidity levels
  helps heat to transmit more into the walls. Application of thermal insulation in buildings apparently
  reduces the running cost of air conditioners by minimizing the heat gain through the walls.


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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN
0976 – 6316(Online) Volume 5, Issue 1, January (2014), © IAEME

        This paper focus on the performance of insulated concrete forms in hot and humid climatic
conditions and also, the hygrothermal performance of the walls. Enough study has been done on the
performance of insulated concrete forms in low temperature climates and there is a need for a
feasibility study on ICF in hot, dry and humid conditions.

2. LITERATURE REVIEW

        Studies have been done all over the world on the performance of Insulated concrete forms in
buildings in low temperature climates. NAHB Research Centre (2001) conducted a test on three
buildings on the comparison of performance of ICF homes with normal framed structures. The study
has shown that ICF homes had an energy reduction by more than 20% [1]
        A Comparative study on ICF building and a wood framed building were done by Petrie Etal
(2001) and the result showed that ICF building consumed 7.5% less energy than the conventional
wood framed building. Performance analysis of a seven storey multi residential building with ICF
construction was done by the ready mix concrete association (2006) in waterloo, Canada. Two ICF
wall specimens were monitored in a study by W. Maref, M.M Amstrong and G. Ganapathy (2012).
The outcomes showed the reduction of peak heating load of the furnace and thus have implications
on the sizing and the cost of the heating equipment [2]. Florian Antretter and Achilles Karagiozis
analyzed the interior temperature and relative humidity distributions in mixed humid and cold
climates [3]. They compared the internal conditions of the building with the standard levels.
Dr. KevanHeathcote compared the thermal performance analysis of three test buildings in Australia.
Recording of temperatures inside and outside the test buildings were analyzed in this paper [4].
        Different combinations of wall and roof plans and shapes were suggested by Amjad A.
Maghrabi (2005). This study was carried out in Makkah, Saudi Arabia [5]. He concluded that, the net
heat transfer through the walls increases or decreases as per the effect of plan shapes of roof and
different wall areas. Abdullah yildiz and GokhanGurlek (2008) presented a study on environmental
analysis of thermal insulation in buildings with different thickness.
        The result of this paper was increase of thermal insulation decreases the heat loss in the
building with increase in the cost of insulation material [6].

3. METHODOLOGY

        Two residential buildings of same volume were selected from phase 7, Mabela, Muscat
governorate of Sultanate of Oman. One building was constructed with the normal concrete block and
the other building was with the insulated concrete block construction.
        Data loggers (Type-EBI 20-TH) were used for temperature and relative humidity
measurement. The data loggers were placed outside the building with shade and inside the building
one foot away from the wall and temperature and relative humidity was recorded during the peak
summer months of July, August and September 2013. Transmission heat gain and moisture transfer
through the wall structures were calculated for analysis for one week during the first week of July.
        For the cooling demand and energy calculations, CAS Anova software [13] was used. This
paper presents the analysis of heat transmission and moisture transfer in the wall systems and the
feasibility study on insulated concrete forms in Oman.

3.1 Factors considered for the feasibility study
1. Transmission heat gain through the walls
2. Actual electricity bills of the buildings
3. Thermal conductivity of the wall
4. Cost of the materials

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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN
0976 – 6316(Online) Volume 5, Issue 1, January (2014), © IAEME

4. DATA ANALYSIS

        Recorded data of temperature and relative humidity was downloaded from the data loggers.
Average maximum temperature and relative humidity of the buildings was taken for the calculations
of heat transmission through the walls, and the moisture transfer through the walls.
        Maximum temperature of 39ºC and RH of 83% was recorded inside the normal construction
building during the month of August. Minimum temperature was recorded inside the ICF building
during the month of July.
        Average RH recorded inside the buildings were above 70% during the three months and the
ICF building recorded a minimum of 69% RH in the month of September. Actual electricity bills of
the buildings and the thermal conductivity of the walls were also considered for the comparative
study.




                               Figure 1: Specification of the Walls




Figure 2:   Data logger output - ICF House              Data logger output – Normal House




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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN
0976 – 6316(Online) Volume 5, Issue 1, January (2014), © IAEME

               Table 1: Heat gain through the wall structures (Monthly Average)
               Month          Wall structure              Heat gain (Watts)
                 June           Normal concrete wall                              2704
                                      ICF wall                                    2240
                 July           Normal concrete wall                              2705
                                      ICF wall                                    1792
                August          Normal Concrete wall                              1803
                                      ICF wall                                    1792




                         2704                   2705


                                     2240


                                                                1792       1803          1792



                         Normal     ICF wall    Normal         ICF wall    Normal    ICF wall
                        concrete               concrete                   Concrete
                          wall                   wall                       wall




                           Figure 3: Heat gain through the wall structures


                                         2:
                                   Table 2 Water vapour pressure levels
        Outside air VP                    Inside air AP                    ressure
                                                             Water vapour Pressure difference
      ICF         Normal               ICF             Normal                     ICF           Normal
     4090           4261               3374               3715                    716            546
     4295           4729               3603               4830                    692            101
     4255           4995               2017               1989                    2238           3006


         Vapour pressure of the air is determined by the ability of the building fabric and contents to
absorb or desorb water vapour. This will reduce or increase the vapour pressure depending on
whether the building is cooling or heating [7].
         Individual “T” test was conducted in SPSS for the temperatures inside the Insulated concrete
form house and the normal concrete structure house. T critical is greater than the calculated T
statistics. From this, it is evident that the performance of the ICF wall structure is better than the
normal concrete wall structure. Actual electricity bills of both the buildings were considered for the
analysis of energy consumed.

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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN
0976 – 6316(Online) Volume 5, Issue 1, January (2014), © IAEME

       Below table shows the difference in units consumed by the buildings per meter square area.
There is a significant difference between the ICF wall and the normal concrete wall in transmitting
heat through the walls. Heat transmission through the walls during the month of august is in
minimum difference as the atmospheric temperature started falling because of the unusual rain in
Muscat.
       Actual electrical bills of the buildings from MEDC (Muscat Electricity Distribution
Company) were considered for the comparison of the electrical energy consumption per one meter
square area. ICF buildings consume 20% to 40% of less energy than the normal concrete building.

                                        Table 3 Actual Electricity Bill
                                                         Total Kwh                                                                 Reduction in units
     Month               Building                        Consumed                                             Units/m²              in ICF Building
       July           Normal building                                   4883                                                 35          21%
                       ICF Building                                     4542                                         27.5
     August           Normal building                                   4164                                                 30          38%
                       ICF Building                                     3042                                         18.4
    September         Normal building                                   4137                                         29.3                40%
                       ICF Building                                     2891                                         17.5



                                        40
                                        30
                             Units/m²




                                        20
                                        10
                                         0
                                             building




                                                                         building




                                                                                                   building
                                                         ICF Building




                                                                                    ICF Building




                                                                                                              ICF Building
                                             Normal




                                                                         Normal




                                                                                                   Normal




                                                  July                      August                 September

                            Figure 4: Electrical energy consumption

4.1 Thermal Conductivity
       Thermal conductivity of the two wall structures were measured with a thermal conductivity
meter [Model No: KD2 Pro]. Thermal conductivity of ICF wall is in the desirable range within
0.74as mentioned in the thermal insulation regulations of Gulf cooperation council countries
(GCC) [8].

                               Table 4: Thermal Conductivity
                       Wall Type                  Thermal conductivity (W/m²)
              Normal concrete wall structure                                                                       1.814
                    ICF wall Structure                                                                                       0.4




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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN
0976 – 6316(Online) Volume 5, Issue 1, January (2014), © IAEME

                                  Table 5: Cost Comparison
                   Type of Structure                Cost/m² of gross wall area
               Normal concrete structure                        3.5 Omani Riyals
                    ICF wall Structure                          6.5Omani Riyals
            Insulated concrete block structure                  5.8Omani Riyals

        Cost of ICF construction is higher than the normal concrete block and the double cavity EPS
insulated concrete block, but ICF construction has the advantage of simple and easy method of
construction, since it has the conventional materials like reinforcement, concrete and EPS insulation
with monolithic construction.
        Number of labor hours required for constructing a building with ICF is comparatively less
with other types of traditional type of construction. An ICF building in Yemen was constructed
within three months in the year 2010.

5. RESULTS AND DISCUSSION

        In this study, the feasibility of using of ICF system in Oman was analyzed. Transmission heat
gain calculation through the walls structures during the peak summer months of July, August, and
September shows that, ICF walls transmits 17% less than normal concrete walls structure. Annual
energy demand for cooling is 36% less in ICF houses than traditional concrete buildings.
        From actual electricity bills of the two buildings it is evident that, ICF houses consume 20%
to 40% less energy than the traditional building. On an average, money spent for electricity in the
ICF house is 36% less than the normal construction.
        Economic Analysis on thermal insulation shows that, it is feasible to have a reduced
operating cost of air conditioners [10]. Initial cost of ICF can be compensated with the less running
cost because of its excellent thermal behavior. Insulated concrete forms are suitable to use in
countries with dry, hot, and humid climate.
        Due to the massive concrete core, the buildings constructed with insulating concrete forms
have the same durability and stability as conventional buildings [11].Even though, since Oman has a
long coastal area, structural rigidity of the ICF wall systems needs to be studied, because of the salt
crystallization and coastal climatic conditions.

6. CONCLUSION

   •   From this study it is clear that, the use of insulated concrete forms in hot and humid climates
       is feasible
   •   Thermal and moisture behavior of ICF is good and the chance of condensation in wall
       structures is not possible
   •   Energy consumption towards the thermal comfort in the buildings is less with ICF buildings
   •   Thermal conductivity of ICF walls is less as per the standard prescribed by Gulf Cooperation
       countries [12]
   •   ICF system offers better and uniform insulation, more airtight envelope, and faster
       construction. However, it costs more than other construction systems [11].
   •   At present, nine residential buildings were constructed and one commercial cum residential
       complex is under construction in Muscat



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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN
0976 – 6316(Online) Volume 5, Issue 1, January (2014), © IAEME

ACKNOWLEDGEMENT

       The author would like to extend sincere thanks to Caledonian College of Engineering, Muscat
and Innovation Building LLC (Member of Ali & Abdul Karim Group and W.J Towell Group) Ghala,
Muscat, for the opportunity provided to conduct this study.

REFERENCES

 [1]    NABH Research Centre (National Association of home builders, USA), (2001), “Costs and
        benefits of insulating concrete forms for residential construction”, Policy development and
        research, US Department of housing and urban Development
 [2]    W. Maref, M. M. Armstrong, H. Saber, M. Rousseau, G. Ganapathy, M. Nicholls and M.C.
        Swinton, (2012), “Field Energy Performance of an Insulating Concrete Form (ICF) Wall”,
        National Research Council, Canada
 [3]    Florian Antretter, Andreas Holim, Achilles Karagiozis, Samuel glass, (2010), “Interior
        Temperature and relative humidity distributions in mixed humid and cold climates as
        building simulation boundary conditions”, Buildings XI conference, ASHRAE
 [4]    Dr. KevanHeathcote, (2007), “Comparative analysis of thermal performance of three test
        buildings”, Earth building research forum, University of Technology, Sydney
 [5]    Amjed A. Maghrabi, (2005), “Comparative study of thermal insulation alternatives for
        buildings, walls and roofs in Makkah, Saudi Arabia”, Journal of Science and Engineering,
        Umm Al Aura University
 [6]    Abdullah Yildiz, GolahanGurlek, Mehmet Erkek, (2008), “Economic and environmental
        analysis of thermal insulation thickness in buildings”, Journal of thermal science and
        technology, Turkey
 [7]    BS 5250:2002, “Code of practice for control of condensation in buildings”
 [8]    M.M. Abo Elazm, A. M. Elharidi, (2010), “A case study of the effect of insulation materials
        on HVAC energy consumption”, World renewable energy congress
 [9]    “Green building regulations and specifications”, Public Authority of electricity and water,
        UAE
 [10]   Eball H. Ahmad, (2002), “Cost analysis and thickness optimization of thermal insulation
        materials used in residential buildings in Saudi Arabia”, Sixth Saudi engineering conference,
        Kind Fahad University of Petroleum and Minerals, Dhahran
 [11]    Dr. Mohammad S. Al-Homoud, (2004), “Performance characteristics and practical
        applications of common building thermal insulation materials”, Journal of building &
        environment, Elsevier
 [12]   “Green building regulations and specifications”, Public Authority of Electricity and Water,
        UAE
 [13]   “CAS Anova”, www.nesa1.uni-siegen.de
 [14]   Sameer Ul Bashir, Younis Majid and Ubair Muzzaffer Rather, “Effect of Rapidite on
        Strength of Concrete in Warm Climates”, International Journal of Civil Engineering &
        Technology (IJCIET), Volume 4, Issue 6, 2013, pp. 126 - 133, ISSN Print: 0976 – 6308,
        ISSN Online: 0976 – 6316.
 [15]   P.C.Madhuraj and J.Sudhakumar, “Assessment of Transient Hygroscopic Behaviour for
        Design of Passive Solar Building Envelope for Hot-Humid Regions”, International Journal of
        Civil Engineering & Technology (IJCIET), Volume 1, Issue 1, 2010, pp. 46 - 54, ISSN Print:
        0976 – 6308, ISSN Online: 0976 – 6316.



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