*3.2.1 Guarded hot box test set-up to measure overall heat transfer co-efficient (U value)*

A Guarded Hot Box test setup was designed and developed in School of Energy Studies, Jadavpur University, India. The setup was constructed following standard

#### *Coalash as Sustainable Material for Low Energy Building DOI: http://dx.doi.org/10.5772/intechopen.101858*


#### **Table 1.**

*Chemical composition of fly ash and bottom ash.*

#### **Figure 5.**

*Grading curve of bottom ash as per IS 383 by sieve analysis [29].*

protocol. This setup was constructed using high insulating material, extruded polystyrene, whose thermal conductivity is 0.027 W/m K. This setup is capable to measure the U-value of any material whose thermal conductance is in the range of 0.1 W/m<sup>2</sup> K to 15 W/m2 K. The testing of U-value of 125 mm thick burnt clay brick wall was done in both the cold side open and closed condition (**Figure 7**).

**Figure 6.** *Particle size distribution for fly ash, used in the experiment.*


#### **Table 2.**

*Design mix concrete of M-25 grade with fly ash/bottom ash substitution separately.*

## *Coalash as Sustainable Material for Low Energy Building DOI: http://dx.doi.org/10.5772/intechopen.101858*


#### **Table 3.**

*Design mix concrete of M-25 grade lime dust and fly ash/bottom ash (no sand).*



#### **Table 4.**

*Masonry mortar mix of MM 3 grade with fly ash/bottom ash substitution separately.*


#### **Table 5.**

*Masonry mortar mix of MM 3 grade with fly ash/bottom ash and lime dust/marble dust.*

Two wooden frames having dimension 500 × 500 were built in order to construct and hold the brick wall samples within those. This was done mainly in order to make it a modular system which could be portable enough so that after experimentation further developments of the samples like plastering, coloring etc. are feasible. Clay bricks, Portland Pozzolana Cement (PPC), sand, fly ash, lime dust and water were the raw materials used for the construction of the brick walls. Dimension of standard Indian burnt clay bricks are 230 × 115 × 75. Two sets of brick walls were developed for the experimentation purpose, one with conventional plaster grade MM5 with cementsand ratio 1:4, another one with same grade of mortar and plaster but with 50% Lime dust and 50% fly ash in place of 100% sand. Dimensions of the both brick walls were 480 × 480 × 115 and 480 × 480 × 115 with 12 mm plaster on either side.

*Coalash as Sustainable Material for Low Energy Building DOI: http://dx.doi.org/10.5772/intechopen.101858*

**Figure 7.** *Guarded hot box test setup with data logging and wall panel under preparation.*
