The basic idea of social housing is to provide affordable housing to people with low incomes. In often cases people who are the benefactors of social housing tend to group up in rather poor and unpleasant surroundings, areas such as polluted harbors or tall concrete buildings resulting in a poorer health state and overall lower quality of life.
Plan H talks about how important it is for people to be in nature, how just being surrounded by greenery comes with many benefits mainly revolving around improving general health and mood, as to why this is important is answered by the general idea of returning to nature.
Considering how important nature is to our general survival and how pleasant it is being surrounded by nature, it is always important to include a form of preservation when considering building housing, especially when its something near a lake or big forest. Properly integrating the environment with housing allows for access to parks, lakes etc. as a form of viewing and relaxed adventure right outside a persons own home, allowing their home to feel more than just a place to sleep.
If you would like to look at more information on Plan H or need more information on the topic feel free to check out the links below.