| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 6 |
0.5%
|
| 1 | Metal, tin or zinc | 0 |
0%
|
| 2 | Tiles | 6 |
0.5%
|
| 3 | Shingles | 0 |
0%
|
| 4 | Thatch or grass | 0 |
0%
|
| 5 | Plastic sheets | 0 |
0%
|
| 6 | Asbestos | 1 |
0.1%
|
| 7 | Multiple materials | 42 |
3.5%
|
| 8 | Concrete | 1100 |
91.7%
|
| 9 | Some other material | 27 |
2.3%
|
| 10 | Could not tell / could not see | 18 |
1.5%
|