In many older homes, the only ventilation available may be from an open window. Ventilation requirements are in place for new construction to help eliminate mold and mildew build up in a frequently wet environment. If your bathroom does not have a ventilation fan, you should consider having one installed. If you already have own you might want to look into the many options available for upgrading.
You have many choices in the style of ventilation units. Some are nothing more than an exhaust fan that directs humid air to the outside. Assemblies are available that also provide a light fixture that can be operated separately from the fan. Some units with lighting can even provide a night light feature. You might even consider a deluxe model that includes a heating lamp. A heat lamp can help warm a cold bathroom up to make getting out of a warm bath or shower less of a jolting experience.
Simple fans units are not expensive and even models with extra features are well priced. Installation of the assemblies does not require bathrooms to be completely torn apart and the job will not take a professional an overly long period of time. Your bathroom will not have to be out of service for days on end. Having an older fan upgraded to a new ventilation assembly will be even easier, the electrical supply and ductwork are already in place.
You should have the work done by a professional bathroom ventilation contractor. The exhaust for the fan must be vented properly without any leaks. Moisture that could build up from a leak in the ceiling or attic crawl space could cause damage to your home. The electrical portion of the job is also important. You need to be protected from any chance of electrical shock and light fixtures do need to be installed correctly if they are over a bath area. Always consider hiring a competent professional contractor for plumbing or electrical work. Many jobs may look easy but they need to be completed correctly to ensure your safety.