Buster builds a boat. In typical Keaton logic, the boat is too big and Buster needs to break the garage door to let it out.
The logic is pure Keaton’s, of course: destroy your home for your pleasure boat.

The comment is also clearly social (or rather, anti-social), as the house crumbles in perfect bourgeois indifférence: as long as Father looks sternly on, and Mother is behind also looking as though nothing had happened, then appearances are OK and the family’s safe…

(earlier, she had reacted to the catastrophic news that the garage had to be busted to clear the boat, with a perfect oh-this-man-will-never-change shrug

Part of the fun here is in the systematic destruction of the family to the point of non-existence (indeed this is fairly frequent in slapsticks: See the end of Along Came Auntie (1926), and the [[bourgeois couple busted]]). After the home, the family loses the car

but soon rallies round Father

In the boat, the family painting (a standard marine view that could be found in any bourgeois interior) is leaking. Dad’s repair skills are not quite up to code:

and Mother’s cooking is not quite what it should be

But just when he’s through destroying the topoi of family life, he pieces it back together and, eventually, the holy family is together, praying:

or saying goodbye:

or walking away together:

…even though that reconstruction is the conclusion of a painstakingly ridiculous belief that they were all drowning together under Father’s enlightened guidance.
(And then, as always, the perfect catastrophic logic of conspiring forces, and the loser’s poetic stance which Keaton does to perfection.