Proper Bathroom Construction Sequence

By James Dulley

Creators Syndicate

Dear James: I am adding a bathroom to my house and doing most of the work myself to save money. What is the proper construction order so that I do not waste time? What items should I consider in the design phase? — Michelle H.

Dear Michelle: You are wise to consider the sequence of construction events before jumping into the remodeling job. Since a bathroom uses so many different types of materials, appliances, storage components and plumbing, it is critical not to get ahead of yourself or you will just end up having to tear out some of the completed work.

Check your local building code for clearances around the toilet, sink, bathtub and shower, etc. It can vary from locality to locality. Typically, the area where a toilet is located must be at least 30 inches across for adequate clearance. There are also minimum distances from the center of the toilet to other fixtures in the bathroom.

Generally, with a floor made of wooden joists, you should complete the wall framing first and then add the plumbing later. Make sure to position the wall studs so that the center of a stud cavity is at the center of the tub faucet. This allows plenty of clearance around the plumbing and shower valve.

With the walls and flooring completed, it is time to install the bathtub or shower stall. Once the tub is installed, cover it and seal it with plastic film to protect it from abrasive dust created as you work on the drywall and tile. Cover this film with heavy blankets and drop cloths to protect it from dropped hammers and chisels.

If you are going to use forced air heating and cooling, install the ductwork at this time. Next, install any electrical wiring, lights and the ceiling exhaust vent fan. To reduce noises from the bathroom, put insulation in all of the interior walls. Using two layers of drywall will also help to block noise.

The last major task is to install the tile around the bathtub or shower stall. Moisture-resistant drywall is easiest to work with, but cement board will hold up better in the long term. Install the tile on the walls and then on the floor. Paint the walls, install the toilet and sink and then add the mirror and towel bar.

Here are a few design tips to consider when planning and constructing your new bathroom:

Consider using cast-iron drainpipes for the plumbing for bathrooms on the second floor. Cast iron damps out more of the noise than standard PVC drainpipes.

With all the plumbing, wiring and other items inside the walls in bathrooms, the stud placement is critical. Consider using double studs at the shower doorframe. Determine where all the items will be located to be sure that studs do not interfere.

To get adequate water flow with less noise, use 3/4-inch piping for the hot and cold water lines. Run 1/2-inch pipe to the individual faucets.

Make sure to size the ceiling fan properly. If it is too small, it will not draw out enough moisture. If it is too big, it will be excessively noisy. A good rule of thumb is that the fan rating in cubic feet per minute (cfm) should be 1.1 times the square footage of the bathroom.

Consider building shower shelves in the corner for shampoo, conditioner, soap, etc.Send your questions to Here’s How, 6906 Royalgreen Dr., Cincinnati, OH 45244 or visit

Send your questions to Here’s How, 6906 Royalgreen Dr., Cincinnati, OH 45244 or visit