1 Bathroom Remodeling. 2  Bathroom. 3  Remodeling. 4  The best place to start with any remodeling project is the budget. 5  Not only will it have a big impact on the type of materials you select for your bathroom renovation, it will also help you set the boundaries of your design. Ventilation. 2  Moisture is your bathroomâs greatest enemy. 3  Mold and mildew will make quick work of any renovation youâve done so be sure to install a vent fan of appropriate CFMs for the square footage of your bathroom. 4  The rough guide is one CFM per square foot for bathrooms of one hundred square feet or smaller.