Governor-Declared Disaster - Replacement Property

If the market value of the replacement is within 120 percent of the market value of the property substantially damaged or destroyed, the factored base year value of the damaged or destroyed property will be transferred to the replacement. (R&T 69(b)(1))

If the market value of the replacement is more than 120 percent of the market value of the property substantially damaged or destroyed, the base year value of the replacement will be the factored base year value of the damaged or destroyed property plus the amount by which the value of the replacement exceeds 120 percent of the value of the property that was damaged or destroyed. (R&T 69(b)(2))

Example: Factored Base Year Value (FBYV) of damaged or destroyed property = $150,000
Market value of damaged or destroyed property = $220,000
Replacement property value allowed for transfer of FBYV (120% * $220,000) = $264,000
Scenario 1: Market value of replacement property = $253,000
  $253,000 is less than $264,000  
  New assessed value of replacement property = $150,000
Scenario 2: Market value of replacement property = $275,000
  Excess market value ($275,000 - $264,000 = $11,000)  
  New assessed value of replacement property ($150,000+$11,000) = $161,000
Scenario 3: Market value of replacement property = $125,000
  $125,000 is less than the $150,000 FBYV of the original property   
  New assessed value of replacement property = $125,000

No. A disaster declaration must have been issued by the Governor for the event that caused the damage. (R&T 69(c)(3))

If the market value of your replacement property is LESS than the factored Prop 13 value of your original property, the replacement will be assessed at its lower market value, (see Scenario 3 above).  There is no need to file a claim form.

In some cases yes, but only if the county in which the replacement property is located has passed a resolution allowing such transfers and you otherwise qualify. (R&T Code 69.3)

You may do either, as long as the comparable replacement property is acquired or newly constructed within three years after the disaster.