How to Prevent and Treat Mold and Mildew in Cabin Bathrooms

Since mold and mildew require dampness to grow, humid environments–all too common at lakefront cottages and cabins–are prime habitats. Here are a few pointers to keeping your cabin loo spic and span.

Prevention

The good news is that a few simple steps can make your bathroom a lot less friendly to these creepy little fungi. It all comes down to keeping your bathroom as dry as possible.

1. Install an exhaust fan.

This can be the single most effective practice to reduce mold from forming. Bathroom fans remove the moisture in the air that allows mold and mildew to grow, but you need to make sure the fan is properly vented to the outside. Otherwise, you may just move your mold and mildew problem into the attic, where it can grow into a very serious problem.

For best results, continue to run your exhaust fan for 30 minutes after you shower. This sounds fine, but if you’re prone to forgetfulness (like certain Cabin Life DIY writers can be) remembering to come back into the bathroom a half hour after your shower can be a bit of a stretch. Heck, I’m already miles out on the lake by then!

Fortunately for us distracted types, anyone with a modicum of electrical skills can replace their standard fan switch with a fan timer switch, which will shut off your exhaust fan after a specified time. Fantech, Broan, Honeywell and DewStop are some of just a few manufacturers of fan timers.

2. Replace your toilet with a model that has a tank liner.

Toilet condensation can be a major source of moisture for mold and mildew. Hot summer days, combined with lots of cabin guests (with lots of toilet flushes) can exacerbate a condensation issue.

When it’s time to replace a worn-out toilet, buy a new one with a tank liner. If your old toilet has years to go, you can buy after-market toilet tank liners ($25), which are made of foam and can be inserted into the tank. These liners insulate the porcelain from the cold tank water, reducing condensation. Note: This project is time-consuming because it involves emptying and thorougly drying the tank, applying an adhesive when installing the new liner, and then letting the adhesive dry.  

3. Install a toilet mixing valve.

Another great way to reduce condensation on your toilet tank is to install an anti-sweat mixing valve. These valves send a mixture of cold and hot water to the toilet tank. These valves are more expensive than tank liners, retailing at about $100, and can take an hour or two to install. However, they provide long lasting solutions to condensation problems around the toilet.

4. Perform a moisture scan.

Check all plumbing fittings for evidence of leakage, and inspect cold water copper pipes for condensation on a warm summer day. It can take very small amounts of moisture to cause big mold and mildew problems, so promptly repairing any leaky fittings and adding pipe insulation to sweating pipe runs can pay big dividends.

5. Install mildew-resistant shower curtains.

A simple way to prevent mildew from getting a toehold in your bathroom is to pick up some mildew-resistant bath curtains ($50).

Treatment

Mold can impact your family’s health if it’s not removed. Fortunately, removal is fairly easy, as there are a multitude of cleaning agents available.

For simple, cost-effective treatment, it’s difficult to beat a diluted (10:1) mixture of bleach and water in a spray bottle.   Just spray affected areas with the bleach mix and allow to dry.   Then spray again and scrub with a bristly brush, wiping up any residue (the first, no-scrub treatment kills the spores before you agitate the mold, preventing further spread).

Alternatively, you can use ammonia, borax or commercial anti-mold/mildew cleaners; just be sure to kill the mold before you start scrubbing.

See also 7 Tips for a Cabin Bathroom Remodel