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INSULATION for INSPIRATION

INSULATION for INSPIRATION

I am building the box. (photo by Donald Parker)

A study of roofing materials and how they affect inside temperatures

By Rosie Parker
6th grade, St. Pius X Catholic School, Portland


Abstract/Summary

Four different types of roofing materials, simulated polar bear fur, white shingles, black shingles, and green roof were tested under a heat lamp to test the insulation of each. Each roof was placed on a roofless box. One thermometer was in the box, one was on top, and one was in a different spot in the room as a control thermometer. From looking at the temperature differences, the green roof has the best insulation and the black shingles has the worst.

Introduction

Question: Which roofing material, out of green roof, simulated polar bear fur, white shingles, and black shingles provides the best protection from heat?

Hypothesis:  Out of different roofing materials that are exposed to a heat lamp, a green roof will have the best insulation.

Explanation of why I did this project: I did this project because I am very interested in the environment. I like to help out the environment too. With this experiment, I can see which roofing material has the best insulation so people won’t have to use as much air conditioning or heaters. This will save a lot of energy. I chose the white and black shingles because many houses have them and I can prove which is better for the environment. I tested simulated polar bear fur because I learned that it is actually clear hollow tubes, and I thought they might trap heat and that it would be interesting to find out. I made a green roof because some buildings have green roofs and they are supposedly better for the environment, so I wanted to test that and find out if they really are.

Experiment

Introduction to my experiment: In my experiment, I will have four different types of roofing material: green roof, simulated polar bear fur, white shingles, and black shingles. I will make a mini roof out of each one. I will then, one at a time, put the roofing materials on a roofless wooden box with a heat lamp over it. For each material, I’ll measure the heat inside the box and outside the box every 15 minutes for 2 hours. This will tell me which material best protects the interior from heat.

Procedure

1)      build a 2 ft. by 2 ft. wooden box without a top

2)      acquire 3 different roofing materials (each 2’ by 2’) :

a)      white shingles

b)      black shingles

c)       soil, heather (Calluna vulgaris), candytuft (Iberis sempervirens), waterproof roof membrane, and a tray for a green roof

3)      obtain 3 digital thermometers with remote sensors

4)      create a 4th roofing material which will simulate polar bear fur

a)      get a 2’ by 2’ tray and fill it with 1” of Model Magic (lightweight air-dry clay)

b)      stick 3” sections of clear drinking straws in the clay, filling the whole area, straws should be inserted at an angle to simulate fur

c)       make sure the straws are as close together as possible

5)      place the box, open end up, someplace where the temperature won’t change

6)      place the remote sensor of a digital thermometer inside the box to show how much the temperature in the box changes over time

7)      place another thermometer 15’ away to show that the room temperature isn’t changing between experiments

8)      place a 3rd thermometer on the roof to measure external roof temperature

9)      for the green roof only, mist the plants with water before each test to keep plants healthy

10)   for each roof type (green roof, simulated polar bear fur, white shingles and black shingles) do the following experiment 3 times:

a)      put the roof on the open end of the box

b)      suspend a heat lamp 18” above the roof

c)       place a thermometer on the roof to show how much heat is on the roof

d)      check and record the temperature of all three thermometers before turning on the heat lamp

e)      turn on the heat lamp

f)       check all three thermometers every 15 minutes over a 2 hour period and record the information at each interval

g)      create a line graph and bar graph of the data

 

Results

Drawings

Rosie Parker Drawing 1

Rosie Parker Drawing 2

Rosie Parker Drawing 3

Rosie Parker Drawing 4

DATA (each test was run three times, indicated by the -1, -2 and-3 in the column headings.

Green Roof (temperature in degrees Farenheit)

Min. 

ambient-1

outside-1

inside-1

ambient-2

outside-2

inside-2

ambient-3

outside-3

inside-3

Average Inside

0

65.7

64.4

62.2

65.5

64.5

64.2

65.5

65.6

64.6

63.7

15

66

150.2

62.1

65.8

119.4

64.2

65.8

106.7

64.6

63.6

30

66

149.9

62.2

65.8

119.3

64.4

65.8

105.2

64.8

63.8

45

66

124.8

62.2

65.7

123.4

64.6

65.8

106.7

64.8

63.9

60

65.8

125.4

62.4

65.5

121.2

64.6

65.8

107

64.8

63.9

75

65.8

125.4

62.4

65.7

125.7

64.6

65.8

109

64.8

63.9

90

65.7

125.4

62.6

65.8

127.2

64.6

65.7

110.4

64.9

64.0

105

65.8

125.4

62.6

65.7

125.7

64.8

65.7

110.3

65.1

64.2

120

65.7

124.8

62.8

65.7

125

64.8

65.8

111.2

65.1

64.2

 

Simulated Polar Bear Fur (temperature in degrees Farenheit)

Min. 

ambient-1

outside-1

inside-1

ambient-2

outside-2

inside-2

ambient-3

outside-3

inside-3

Average Inside

0

66.7

66.2

67.3

65.3

65.6

66.2

65.7

65.8

66.6

66.7

15

66.7

111.9

68.4

65.5

117.5

66.6

66

115.5

67.1

67.4

30

66.9

110.6

69.6

65.8

114

68.4

66

116.7

68.7

68.9

45

66.9

111.2

70.9

65.8

112.6

69.8

66

118.5

70.2

70.3

60

66.9

109.9

72

65.8

114.6

71.1

66.2

119.6

71.4

71.5

75

67.1

108

72.9

65.8

114.9

72.1

66.2

122.7

72.7

72.6

90

67.3

130.2

73.6

65.8

122

73

66.2

123

73

73.2

105

67.3

129.9

74.3

65.8

116.9

73.8

66.2

123.2

74.3

74.1

120

67.3

126.6

74.8

66.2

116.2

74.5

66

123.8

74.8

74.7

 

White Shingles (temperature in degrees Farenheit)

 Min.

ambient-1

outside-1

inside-1

ambient-2

outside-2

inside-2

ambient-3

outside-3

inside-3

Average Inside

0

65.8

67.4

67.6

65.8

65.5

66

65.5

66.0

66

66.5

15

66.2

117.5

70.7

65.7

107.8

68.5

65.3

132.2

69.1

69.4

30

66.2

125.4

73.6

65.7

113.9

71.8

65.5

142.1

72.9

72.8

45

66.2

125.4

75.4

65.8

117.8

73.9

65.7

144.1

75

74.8

60

66.0

125.4

76.6

65.8

115.5

75.6

65.7

143.9

76.6

76.3

75

66.0

125.6

77.5

65.7

115.5

76.6

65.5

144.1

77.7

77.3

90

66.0

126.5

78.1

65.7

115.8

77.4

65.3

144.6

78.3

77.9

105

66.2

128.4

78.4

65.8

114.8

77.1

65.3

144.8

78.8

78.1

120

66.4

125.7

79

65.8

115.3

78.1

65.7

142.8

79.2

78.8

 

Black Shingles (temperature in degrees Farenheit)

 Min.

ambient-1

outside-1

inside-1

ambient-2

outside-2

inside-2

ambient-3

outside-3

inside-3

Average Inside

0

66.9

66.3

65.7

65.8

67.2

67.3

67.3

67.1

69.1

67.4

15

67.6

124.7

69.4

65.8

129.3

71.1

67.3

131.9

73.2

71.2

30

67.1

133.1

72.9

66

140.9

74.8

67.1

140.7

76.8

74.8

45

67.1

140.1

75.6

66

143

77.2

67.1

138.2

78.6

77.1

60

66.9

140.7

77.9

66.2

143

78.6

67.1

140.5

80.1

78.9

75

66.7

143.6

79

66.2

143.7

79.7

67.1

139.8

80.8

79.8

90

66.6

143.6

80.1

66.4

143.2

80.4

67.1

140.1

81.1

80.5

105

66.4

143.4

80.6

66.4

143.4

81.1

66.9

140.5

81.5

81.1

120

66.5

143.2

80.8

66.4

143.4

81.5

66.9

140.3

81.5

81.3

 

Average Inside Temperature

(degrees Farenheit)

Min.

White

Black

Polar Bear

Green

0

66.5

67.4

66.7

63.7

15

69.4

71.2

67.4

63.6

30

72.8

74.8

68.9

63.8

45

74.8

77.1

70.3

63.9

60

76.3

78.9

71.5

63.9

75

77.3

79.8

72.6

63.9

90

77.9

80.5

73.2

64.0

105

78.1

81.1

74.1

64.2

120

78.8

81.3

74.7

64.2

 

Graphs

Rosie Parker Graph 1

 

 

Rosie Parker Graph 2

 

 

Rosie Parker Graph 3

Rosie Parker Graph 4

Summary

Rosie Parker Graph 5

Rosie Parker Graph 6

Discussion

Science behind why things happened

Green roof – The green roof worked the best because the plants have more water in them than the air, so the water from the plant evaporated. When the water evaporated, it cooled off the plants and the area around it. This is kind of like our sweating where it cools us down. When extra water that traveled up the xylem and is coming out of the leaves, it’s called transpiration.  Also, the green roof was a lot thicker because of the dirt; this thickness also provided insulation.

Rosie Parker Diagram 1

This shows the different layers of a green roof. My roof included vegetation, growing medium, waterproof layer, support panel and structural support. Including the additional layers such as thermal insulation and a drainage layer, would give the house even better insulation.   (Source: National Research Council, Institute for Research in Construction)

Simulated polar bear fur - Polar bears keep themselves warm by trapping the sun’s heat in their fur. Their fur is actually a bunch of clear, hollow tubes. It traps the heat and channels it down to their skin, which is black. My roof base is white so it will reflect heat/light better. The simulated polar bear fur provided the second best insulation. I think the straws carried the heat down to the white clay where the light/heat was reflected and trapped in the straws.

Biomimicry: looking at different aspects of nature and applying characteristics from it to a new design for a product.

Rosie Parker Diagram 2

 

 

Picture (a) shows the clear fur and black skin. I used a white base to reflect light instead of absorbing it.  Picture (b) shows how sunlight goes into the fur and is absorbed by the black skin. The same thing will happen with my roof except it will be reflected and not absorbed. (Image by Stegmaier in “Bionics in textiles: flexible and translucent thermal insulations for solar thermal applications.”)

White shingles - White shingles reflect light. White is the presence of all colors, which means that it reflects all colors. When it reflects all the colors, it’s reflecting all the light too. The white shingles had the third best insulation. Also, the white shingles are quite similar to the black shingles in the sense that they have a lot of black on them too, so they will still not work the best.

 

Black shingles - Black absorbs heat because all colors either absorb or reflect certain wavelengths of light. The color of something depends on how many wavelengths of light it reflects. Black absorbs all wavelengths of light, so no matter what light you shine on a black object, it’ll always absorb all of it. That’s why black appears black in the first place. The black shingles had the worst insulation. When the roof absorbed the light, the inside heated up because the heat did not only stay above the shingles, but it went inside the house/box too.

Comparing results with what I researched

Green roof- My hypothesis was supported because the green roof did end up working the best by far. In the first test, the temperature on the roof went way up and then way down. I think this is for the same reason I thought the green roof would do well. I think the plants hadn’t started to do transpiration yet, so they really heated up. After it got really high, it went down to a normal temperature. I think that’s when it started to do transpiration. Since I was using the same plants, and the one I just explained was the first test, I think the other tests didn’t do the same because the plants had already started transpiration.

Simulated polar bear fur- My hypothesis was supported because the simulated polar bear fur did end up as I was expecting it to. The inside stayed somewhat cool while the outside heated up only a little bit because the heat got trapped inside the straws, not around or right above them. Both the roof and the inside of the box heated up the second least.

White shingles- My hypothesis was supported because the white shingles did end up having ok results, but they still weren’t very good. All the thermometers went up steadily for the most part. The roof got to be close or about 130 degrees Fahrenheit for each test. This shows that I was correct about the white reflecting a lot too.

Black shingles- My hypothesis was mostly supported because the black shingles had the worst insulation by far. It was refuted, however, that the black wouldn’t reflect any of the heat or not much because out of all the tests, the roof temperature ended at about 141 degrees Fahrenheit. For each test, the inside ended at about 81 degrees Fahrenheit showing that I was supported in the fact that the black did absorb a lot of heat.

What I’d do differently, ways I can modify/expand my experiment

If I had more time and money and was doing my experiment on a summer day, I’d build four separate boxes , one for each roofing material, and put them outside on a sunny day. This would make my results more accurate because the roofs would have the same starting and outside temperature. It would also be under the real sun instead of artificial light.

The data from the roof top temperatures is also interesting.  Does heat reflected into the atmosphere cause problems? If so, what kind of roof helps that?

 

Conclusion

Overall, the green roof did the best, the simulated polar bear fur came next, the white shingles were after the simulated polar bear fur, and the black shingles were the worst.

 

Acknowledgements

The following people or organizations helped me with my project:

·         My mom and dad, because they kept me on task and helped me with all my papers, my poster, and my project;

·         Mrs. Sebert, because she gave me the opportunity to do this and helped me with my papers;

·         My brother, Owen, because he helped by showing me kind of how I was supposed to do things because he’s done a science fair before;

·         Cascadia Region Green Building Council, for giving me information about the different kind of green roofs there are;

·         Todd Schwartz of Willamette Roofing for providing me with black shingles, white shingles, and waterproof roof membrane.


References

Benyus, Jenine. “What is biomimicry?” [Online]. Retrieved March 17, 2012 from www.biomimicryguild.com.

Bureau of Planning and Sustainability. “Ecoroofs.” [Online]. Retrieved February 21, 2012 from www.portlandonline.com.

Green Roofs for Healthy Cities. “About Green Roofs.” [Online]. Retrieved March 17, 2012 from www.greenroofs.org.

Hari. (Edited September 30, 2011). “Why do Dark Colors Absorb Heat?” [Online]. Retrieved February 26, 2012 from www.knowswhy.com.

Oregon Zoo. “Polar Bear.” [Online]. Retrieved February 19, 2012 from www.oregonzoo.org.

Reed, Paul. (Edited 2012). “What is a UV Absorber?” [Online]. Retrieved February 26, 2012 from www.wisegeek.com.

Roofmeadow. “Greenroof Details & Specs.” [Online]. Retrieved February 21, 2012 from www.roofmeadow.com.

Stegmaier, T., Linke, M. & Planck, H. “Bionics in textiles: flexible and translucent thermal insulations for solar thermal applications.” Philosophical Transactions of the Royal Society (Mathematical, Physical, and Engineering Sciences) Retrieved march 17 from http://rsta.royalsocietypublishing.org.

 

 

 
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