Garage addition project: part 8, plumbing rough

Your garage addition project may have a plumbing rough stage, or if there is no plumbing involved in your construction, you may be able to skip this stage. The plumbing rough consists of installing the supply, drain, and vent lines for any bathrooms, wet bars, kitchens or any other fixtures that use water. The plumbing rough also involves running any gas lines needed for appliances, the HVAC system, hot water heaters, or a gas fireplace.

Plumbing rough considerations

Plumbing leaks can be very costly in a finished home and can really put a damper on the enjoyment of your new space. Of course, gas leaks can be extremely hazardous, so it is important that the plumbing contractor, you, or your general contractor knows what he or she is doing. All plumbing and gas lines should be pressure-tested prior to drywall being installed. Many local inspectors require that this is done to pass the plumbing rough inspection, but if this isn't a requirement in your area, you should still insist that the contractor does it.

The plumbing contractor should take care that there are no water lines in unconditioned spaces or exterior walls. This is especially important if you live in a part of the country that gets very cold during the winter; many frozen pipes that thaw and cause leaks are due to this consideration being ignored.

Take a picture of your plumbing rough

Your plumbing contractor should install nail plates everywhere a plumbing or gas line passes through a framing member. This precaution helps prevent the drywall or trim contractors from accidentally driving a nail into a pipe while doing their work. It can also help prevent you from making a big mistake if you are mounting an elk head, hanging artwork, or installing a towel rack in the future.

Many homeowners find it helpful to take pictures of their plumbing roughs prior to drywall being installed. If you ever do any modifications to your home addition, such as adding an interior door or a recessed cabinet in a bathroom, it can be helpful, and save drywall work, to know exactly where your plumbing and gas lines are located.