2. Did you know? If every house in the United Kingdom were to turn their heating down by just 1 0 C, one power station could be entirely shut down! STARTER What are the advantages in shutting down a power station?

3. Wall Designs Early houses consisted of a single brick or stone wall that separated the inside of the house from the elements. Later on builders introduced a second wall. This created an air gap and a secondary wall that separated the inside of the house from the elements. At present these air gaps (or cavities) are filled with an insulating foam that contains air pockets. This is known as cavity wall insulation.

4. Filled cavity walls reduce the heat loss from a home. This saves both heat energy and the home owner money. The foam is an exceptional insulator and reduces heat loss through conduction! The foam also contains air pockets that lock in convection currents!

5. Challenge!?! There has been some controversy in the media recently with stories claiming that “Cavity wall insulation is a con and is just a way for builders to make money!” You have been asked by your local council to come up with conclusive evidence to dispel this myth! There are two options!

6. Here are the options Option 1 Follow the link to view the animations. Using the results draw a graph displaying all three practical’s. Draw your own conclusions. Which was the best at retaining heat? Option 2 You will be allocated to a group. Each group has a specific practical to carry out that is shown in detail on the worksheet. Plot a graph of your results and present your findings to the class. Draw your own conclusions. Which was the best at retaining heat? Were the media correct or does insulating your walls reduce heat loss?

7. Animations Click on the following to view them: Single wall animation Cavity Wall animation Insulated Cavity Wall animation Model results for the practical

8. PlenaryFill in the blanks Originally houses were built with a single wall. However, this was not a very good method of retaining heat so instead a second wall was introduced creating a cavity. This cavity is now filled with some insulating foam that contains air pockets which reduces heat loss by conduction and convection. The new method saves both heat energy and money. cavity conduction water energy pockets money convection single foam single cavity foam pockets conductionconvection energymoney ***************Click here for the drag and drop version***************