The answer to 'what size rewiring do I need' is that the size of the electrical wiring needed for a home rewiring project depends on the size and layout of your home, as well as the electrical load and appliances you need to power. In general, most homes will require 12-gauge or 14-gauge wiring for general lighting and outlets, while larger appliances like stoves, ovens, and air conditioners may need 10-gauge or 8-gauge wiring. The specific wiring size needed should be determined by an experienced electrician who can assess your home's electrical needs.
It's important to note that rewiring a home is a complex and potentially dangerous task that should only be undertaken by a licensed and insured professional electrician. Attempting to rewire your home without the proper expertise can lead to serious safety hazards, such as fire or electrical shock. If you're considering a home rewiring project, it's best to consult with a local electrical contractor who can provide a comprehensive assessment and recommendation for the appropriate wiring size and installation.