How are most MH basement compartments made

So after trying to find how water got into my lower compartment in front of the rear tire I found the construction of these compartments to be cheesy.
basically they are thin luan or similar and covered with thin very thin aluminum, like foil...
For what these things cost cant they build them better ? I thought Winnebago was better made...if that's the case what do people like Thor build their compartments like ?
Seems like leaving the edges raw is only asking for ROT !
Im disappointed to say the least