The huts on the beach represent a sense of security, especially for the littluns. Ralph confides in Simon and Jack in chapter three that the littluns are plagued by nightmares and toss and turn at night. Ralph refers to the huts as "shelters" and forcefully tries to convince Jack of their importance: "We need shelters," as opposed to hunting which Jack has been wasting his time on lately (51). For Ralph, the huts are a necessity; as chief, he feels duty-bound to protect the littluns--not just from the elements, like rain--but also from the alleged beast.
Toward the end of Ralph and Jack's debate concerning the huts, Ralph brings up the threat of the beast, coupled with the littluns' nightmare:
"'They talk and they scream. The littluns.[...] As if--'
'As if it wasn't a good island.' [...]
'So we need shelters as sort of--'
'That's right'" (52).
The boys' exchange reveals the significance of the shelters. By building them, Ralph attempts to inject some normalcy into the boys' lives, a temporary home, but also one to give them a sense of security. The huts on the beach protect them from the weather and storms, but also more significantly will give a much needed morale boost to the boys who so desperately need a way to feel connected to their former lives.
The huts on the beach represent order and civilization. The children must discipline themselves to build them, to use proper latrines, and to follow other rules. Ralph is a leader in this regard, but the children instead want to play. When Ralph tries to talk seriously to the children in Chapter 5, to get them to “shape up” so that there is some order on the island, he reminds them that he and Simon were the only two that participated in building all three of the huts. The huts give them a sense of community within, a place together to be safe from everything they fear in the night, which is darkness and the “beast” they think within it.