Prevent Mold and Mildew After a Remodel
In a San Diego bathroom, mold is nearly always a sign of poor ventilation or failed waterproofing, not a sign you need to scrub harder. Nail the fan, the slope, and the membrane during the remodel, and you won't be dealing with mold headaches afterward.
What you'll learn
- Sizing a bathroom exhaust fan for a San Diego bath: how CFM works with square footage and duct length
- What separates a vented fan from a recirculating fan, and why that gap matters in a steamy bath
- The waterproofing layers installed behind tile in a new shower, and the job each one does
- The 20 minute ventilation habit that stops 90 percent of bathroom mold growth
Step by step
- Get the exhaust fan size right. A bath of 50 to 80 square feet calls for a 50 to 80 CFM fan. A primary bath of 100 to 150 square feet calls for 100 to 150 CFM. When the duct run goes over 8 feet, add 25 percent to the CFM to offset resistance.
- Make sure the fan sends air outdoors. If it's ducted, it runs through a side wall or up through the roof. A recirculating fan blows air back into the bathroom after passing it through a charcoal filter, and that won't deal with moisture. For a wet bath, a ducted fan is the only option that works.
- Put in a humidity sensor or a timer. Running the fan for 20 minutes after a shower clears 80 percent of the moisture load. A $30 countdown timer or a $40 humidity-sensor switch handles the times someone forgets to turn the switch on.
- Don't skip the waterproofing layer. In a modern San Diego shower, there should be a PVC liner, a RedGard liquid membrane, or a Schluter Kerdi membrane behind the tile. Every one of those is a genuine waterproofing system. Cement board by itself won't stop water.
- Look at the shower floor slope. A shower pan should drop 1/4 inch per foot toward the drain. If water pools at the edges of the pan, the slope was likely missed, and that standing water feeds mold.
- Keep the fan running through the shower and for 20 minutes afterward. Give a bath 20 minutes of fan time after every shower and it stays dry at the grout lines, the curb, and the corners. The best mold prevention habit is also the least expensive.
In a San Diego bath remodel, a vented exhaust fan is the upgrade that returns the most for its cost. A $200 to $400 fan paired with a $30 timer switch heads off the kind of moisture damage that turns a $30,000 remodel into a $50,000 rebuild within 8 years.
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Keep learning.
Plan a Bathroom Layout That Actually Works
When a San Diego bathroom remodel goes wrong, it's usually the layout that's to blame, not the tile or paint. Nail the clearances, fixture positions, and door swings on paper first, and everything after that moves quicker and costs you less.
Choose the Right Tile for a Bathroom Remodel
In a San Diego bathroom, tile shapes the look and takes up more of the budget than any other piece. Choose the right material, size, and finish and the space feels fully remodeled, even if the fixtures are stock.
Decide Between a Shower, Tub, or Both
In San Diego, most homeowners hold onto at least one tub for resale purposes, even when it goes unused. What works best comes down to who lives in your home, what your lot allows, and how many years you expect to stay.