Fern's pizza oven
Here's a description of the contestant's attempt. Someone's probably working on collecting some images to illustrate it.
Fern brings in a fancy outdoor pizza oven. She then admits that she doesn't really enjoy spending time in her garden because she lives in an area of southeast London where she has to overhear drugdealers arguing, and women dry-heaving, if she goes outside. Greg awards the pizza oven last place, based on the fact that it looked like Fern had set fire to the outside of it.
(Written by Karl Craven)