You are asked to design an insulated stud timber wall and have the following materials available: Outer skin materials • • Plasterboard 8 mm thick (k= 0.3 W/m.K) Plasterboard 12.5 mm thick (k = 0.3 W/m.K) Insulated Plasterboard 25 mm thick (k = 0.2 W/m.K) Timber studs available (k = 0.1 W/m.K) • 50 mm x 100 mm • 50 mm x 120 mm 50 mm x 150 mm Insulation layers ● Glass fibre insulation (k= 0.05 W/m.K) Polyisocyanurate insulation (k= 0.025 W/m.K) Sheeps wool insulation (k= 0.04 W/m.K) Wall construction should consist of two outer plasterboard skins, followed by an appropriate stud/insulation infill layer. Studs can be placed vertically at 400 mm or 600 mm intervals and you may ignore any requirement for horizontal studding. 1) Draw a plan (top view) cross section of your wall indicating dimensions, spacing and material choices. 2) Calculate the thermal resistance of your wall. 3) If the internal convective heat transfer coefficient in room one is 10 W/m²K and in the second room it is 15 W/m²K. Calculate the total heat transfer through the wall assuming room one is maintained at 22°C and room two is at 16°C stating clearly any assumptions made.

You are asked to design an insulated stud timber wall and have the following materials available: Outer skin materials • • Plasterboard 8 mm thick (k= 0.3 W/m.K) Plasterboard 12.5 mm thick (k = 0.3 W/m.K) Insulated Plasterboard 25 mm thick (k = 0.2 W/m.K) Timber studs available (k = 0.1 W/m.K) • 50 mm x 100 mm • 50 mm x 120 mm 50 mm x 150 mm Insulation layers ● Glass fibre insulation (k= 0.05 W/m.K) Polyisocyanurate insulation (k= 0.025 W/m.K) Sheeps wool insulation (k= 0.04 W/m.K) Wall construction should consist of two outer plasterboard skins, followed by an appropriate stud/insulation infill layer. Studs can be placed vertically at 400 mm or 600 mm intervals and you may ignore any requirement for horizontal studding. 1) Draw a plan (top view) cross section of your wall indicating dimensions, spacing and material choices. 2) Calculate the thermal resistance of your wall. 3) If the internal convective heat transfer coefficient in room one is 10 W/m²K and in the second room it is 15 W/m²K. Calculate the total heat transfer through the wall assuming room one is maintained at 22°C and room two is at 16°C stating clearly any assumptions made.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter42: Heat Gains And Heat Losses In Structures

Section: Chapter Questions

Problem 11RQ: If a wall is made up of four different materials, all layered one on top of the other, how will the...

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