Vol 15, No 2 (2011) > Articles >

Analytical and Computational Simulation Approaches to Design Low Energy Glass Block

Floriberta Binarti 1 , Agustinus Istiadji 1 , Prasasto Satwiko 1 , Priyo Iswanto 2


  1. Program Studi Arsitektur, Fakultas Teknik, Universitas Atma Jaya Yogyakarta, Yogyakarta 55281, Indonesia
  2. Jurusan Teknik Mesin, Fakultas Teknik, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia



An environmentally friendly process was developed to produce a low embodied energy glass block from waste glasses. The energy efficiency of the glass block is represented by its thermal conductance (U) <3.177 W/m2.K and solar transmittance (SHGC) ≤0.25 as well as visible light transmission (VT) ≥0.27. A cavity was applied to reduce U value while insignificantly reducing VT. Analytical method was used to calculate the U value of glass blocks, ignoring the effect of convection. Ecotect program was used to analyze light level (VT) and heat load (SHGC) of each model. Effect of convection was simulated using a CFD program, which showed air velocity inside the cavity and temperature gradient in glass blocks. Comparing to an application with 3 mm float glass, energy efficiency obtained through applying the glass blocks could reach 96%. This simulation study ignored the presence of adhesive among glass layers that potentially reduces the VT and the SHGC of the glass blocks.

Keywords: analytical approach, cavity, computational simulation, glass block, low energy
Published at: Vol 15, No 2 (2011) pages: 115-122

Access Counter: 1165 views, 823 PDF downloads, .

Full PDF Download


British Standards Institute, PAS 102: Specification For Processed Glass for Selected Secondary end Markets, wn.com/British_Standard_Institute, 2005.

G. Milne, C. Reardon, Embodied Energy, http://www.yourhome.gov.au/technical/fs52.html, 2008

ASHRAE, ASHRAE Handbook: Fundamental, ASHRAE, Atlanta, 2001, p.30.

Mulia Glassblock, Architectural Specification, www.muliainc.com/glassblock/products/MuliaGlassblockArchSpec.pdf, 2009.

P. Corning, LightWise Architectural Systems Energy Efficient Glass Block Panels, http://www.twincitiesglassblock.com/images/GB-185_1-5.pdf, 2010.

P.R. Atherton, Cold Seal Glass and Energy Efficient Panel, US20100139191, 2010.

International Institute of Energy Conservation & USAID, Energy Conservation Building Code 2006,

Bureau of Energy Efficiency, New Delhi, 2006, p.67.

A. Gustavsen, J.V. Thue, J. Building Phys. 30/3 (2007) 217.

E. Ng, Conf. Proc. of the IBPSA Conf., Rio de Janeiro, 2001, p.1215.

C.F. Reinhart, M. Andersen, J. Energy Build 38/7 (2006) 890.

Ecotect v.5.6, User Manual, http://www.squ1.com, 2008.

P. Satwiko, N. Locke, M. Donn, Proc. of the 32nd Annual Conf. of the Australia and NZ ASA, Wellington, 1998.

J.M. Horan, D.P. Finn, Proc. of Int. Conf. Passive Low Cooling for the Built Environment, 2005, p.53.

M.J. Braun, V.V. Kundriavtsev, B.M. Steinetz, M.P. Proctor, J. Rotating Mach. 9/3 (2003) 171.