Preventing Damage to Home Additions
The building code does have any guidelines about how best to attach an addition to the main house. How this connection is made is left up to the contractor. Contractors will put in enough nails to make sure the addition does not fall down from gravity, but will rarely check to see if the addition will separate from the main house in an earthquake. Because they have no code to follow, so the building inspector will pass anything that looks reasonably effective in keeping gravity from separating the two.
Floor to Floor Connectors
The purpose of Floor to Floor Connectors is to make sure these two floors do not separate. Floor to Floor can be made of steel bolts, large screws, special hardware known as Hold Downs, or custom made wood connectors designed on site as circumstances require.