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Resource Efficient Remodeling in Your Bathroom

There are many ways to save when remodeling your bathroom. Consider measures that save both energy and water. Low flow shower heads, faucets and toilets save a significant amount of water without sacrificing performance. Conserving hot water saves on energy used to heat the water. Sealing leaks prevents moisture damage and avoids related health problems. Efficient ventilation fans and lighting can also add to your savings and comfort.

Low Flow Fixtures


The aerators in low flow fixtures cut your water usage, but not your comfort. These faucets use as much as 40% less water than conventional faucets, or about 2.5 gallons per minute compared to the standard 4 gallons per minute. Though less water is delivered, few people notice a difference at the tap. Low flow faucets and showers are simple and inexpensive to install. Installation is no different than that of conventional faucets. Directions will be included in the product packaging.

If you are not ready to replace your faucets entirely, aerators may be added to your existing faucets. Aerators can be found in any hardware store and typically cost less than $5. f simply adding a new aerator to the fixture, unscrew the old aerator. Apply white pipe tape around the threads of the new aerator. Put the rubber washer inside the end and screw the new aerator onto the faucet. Run the water to test, making sure no water leaks out the side. If there is a water leak, gently tighten by hand until it is sealed tightly.


Low flow shower heads save about 50% of the water a conventional shower requires, or about 2.5 gallons per minute as compared to the conventional 4 or 5 gallons per minute. A good fixture will save water and still deliver a great shower. Using less hot water for your shower also saves energy because less water must be heated for the shower. Aerators can also be added to existing shower heads if you are not ready to replace the entire unit. Various models are available that increase spray velocity, reduce splash, while saving both water and energy.


New toilets require less than one-third the volume of water of older models. If you are not planning to replace an existing toilet, you can install water-saving devices such as a toilet dam. A toilet dam can be made by simply filling a small plastic water bottle and placing it in the tank. Be sure to place it away from the moving parts in the tank so as not to interfere with flushing.

Ventilation Fans

Taking a shower and running the faucet releases a lot of moisture into the air. As your bathroom steams up, the moisture can condense on surfaces and wick through porous materials. This can cause mold and decay in materials. Mold can also cause health problems, particularly for people with respiratory illnesses. A ventilation fan will help remove the moisture from the bathroom and force it outdoors.

ENERGY STAR qualified ventilating fans consume about 65% less energy than standard models. They incorporate advanced features that enable improved performance, quieter operation, and longer lifetime. Consider adding a timer so the fan automatically shuts off.


Replace incandescent light bulbs with compact fluorescent bulbs (CFLs). CFLs fit in the same fixtures as standard light bulbs so there is no need to replace all of the fixtures in the room. You can get the same bright, warm light from CFLs as standard incandescent light bulbs while saving energy and money.

If you are replacing your lighting fixtures, choose ENERGY STAR qualified fixtures that can also incorporate CFLs for greater energy savings. ENERGY STAR qualified lighting fixtures and CFLs last longer than conventional products.

Seal Leaks - Caulk and Grout

The outside walls behind tubs or showers are often poorly insulated and air-sealed. Opening these walls as part of the remodeling project provides an opportunity to seal air leaks with caulk or expanding foam, and installing insulation.

Watch for any gaps of holes in the caulking around your bathtub, sink and toilet and any cracks in the grout. Check for signs of mold and clean thoroughly if found. Cracks in the grout or caulk may lead to water and air leaks. Water leaks may lead to mold problems and can rot out the tiles, walls or other surrounding area. Also be sure to air seal around plumbing and electrical penetrations, especially recessed lighting.

Caulking can be easily repaired by following the instructions provided by the supplier, which should be labeled on the tube. Caulk comes in cartridges that will be inserted into half barrel caulking guns. For small caulking jobs, you can find it in small squeeze tubes or ropes. Expect to use about one cartridge for faucets and more for bathtubs.

The surface where the caulk will be applied should be cleaned thoroughly and dried to ensure proper application of the new caulk. In general, about a half inch of the caulking cartridge nozzle should be cut off at a 45 degree angle and the tip should be punctured. Once the caulk is applied, you can finish the surface with a moistened finger or something smooth.

The Bathtub Doctor offers free detailed information on how to caulk and grout in your bathroom. Grout requires regular maintenance. Following a maintenance schedule will help keep your tiles adhered to the wall for a long time. Neglect may cause them to loosen and begin to fall as the wallboard behind them becomes wet and breaks down.


Insulating your bathroom will depend on local energy code requirements. In most cases, the minimum requirement is R-19 in the exterior walls and R-30 in the ceilings, but you should check here for region-specific recommendations. If you are remodeling a room, this is a great time to check on the level of insulation you currently have and the condition of your existing insulation.

If your existing insulation has been damaged by moisture or any other means, it is a good idea to gut the bathroom and reinsulate. Because this is a room where moisture is common, a low permeability vapor barrier should be installed on the inside surface of the framing to avoid rot within the walls. The most convenient insulation options in your bathroom are blown-in fiberglass or cellulose insulation.

It is important to insulate all plumbing holes in your bathroom to prevent freezing. Be sure to insulate beneath the tub and around pipes.

 Water Heater Installation
 Caulking How-To
 Insulation Basics
 Solar Hot Water Heaters
 ENERGY STAR qualified Ventilating Fans
 ENERGY STAR qualified Lighting
 Caulking Instructions from the Bathtub Doctor
 Toolbase: Mold and Moisture
 Overview of Retrofit Strategies: A Guide for Apartment Owners and Managers
 Water Use It Wisely
 Additional Water Links

Content updated July 9, 2004

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