Investigating Science 11–12 · Year 11

A model house: testing wall and window materials for heat loss

Module 3: Scientific Models

Practical, model not builtLow risk

This site has no interactive model of its own. Where a step or a material names a Concept Studio model, simulation or tool, it has not been built; an external simulation a step names (for example PhET) is not part of this site.

The idea

A small model house and a heat-loss equation both predict how building materials change indoor temperature, and the model’s limits (scale, no sun, no draughts) are as instructive as its results.

What you need

the ATSE STELR Sustainable House Kit, or a 30 cm cardboard cube with interchangeable wall panels
test panels: 3 mm acrylic or glass, double-layer acrylic with an air gap, 20 mm polystyrene foam, cardboard
a low-voltage heating panel or 12 V resistor heater with voltmeter and ammeter to measure its power, two temperature sensors with a data logger

How to do it

Build the model with insulation panels on every face except the one being tested.
Log inside and room temperatures every 30 s with the heater on until the inside temperature is steady (about 20 minutes).
Record the heater power P = VI and the steady temperature difference ΔT.
Swap in each test panel and repeat.
Calculate an effective heat-loss coefficient for the whole box, U = P/(AΔT), and rank the panels.
Scale up: use the YourHome U values to compare heat loss through a house’s windows, and list the ways the model differs from a real house.

What you should see

The foam panel gives the largest steady temperature rise and the single acrylic or glass panel the smallest, with the double panel between. As a worked calculation, a 10.0 W heater holding a 0.30 m cube (0.54 m² of surface) 12.0 K above room temperature corresponds to an effective U of 1.54 W/(m²·K); the learner calculates their own value for each panel. YourHome gives 6.2 W/(m²·°C) for clear single glass in aluminium frames and 3.1 for a window with half that U value, such as argon-filled double glazing in less-conductive frames, so 70 m² of windows 15 °C colder outside loses 6.2 × 15 × 70 = 6510 W, halved to 3255 W by the better glazing.

What changes

What you change: test panel material
What you measure: steady inside temperature rise above room temperature
What you keep the same: heater power
same other five faces
same sensor positions
room temperature and no draughts

Common misconceptions

Each of these ideas is wrong, and the activity is a chance to test it.

Insulation produces heat.
Glass keeps heat in because it is solid.
A model that is smaller than the real thing behaves in exactly the same way.

Safety card

Low riskLearners carry it out

Hazards

hot heater surface
cut edges of panels

Controls

low-voltage supply only
do not touch the heater until it cools
handle glass panels with gloves or use acrylic

Note

Heat or hot water is used: follow the NSW Department of Education Chemical Safety in Schools (CSIS) package, Section 1, and record a RiskAssess risk assessment before the lesson.

Curriculum references

The NSW syllabus outcomes and Australian Curriculum v9 codes this activity supports. They are references, not a verified or complete curriculum alignment.

Investigating Science Stage 6 Syllabus (2017), NESA; currentINS11-10 INS11/12-2 INS11/12-3 INS11/12-4
Australian Curriculum v9No Australian Curriculum v9 code is listed.

Sources

The pages the author read to write this activity.

All Concept Studio activities