Home and Garden | Replacing a Wall-Hung Lavatory - Plumbing

The information given here pertains to making a one-to-one lavatory exchange, that is, replacing the old lavatory with a new wall-hung lavatory of similar size.

Before removing the old one, turn off the water shutoff valves or the main valve. If you shut off the main valve, drain the system to the lowest fixture. Open faucets at high elevations to complete the drain-down task. If you plan to reuse existing hardware components (faucet, drain, tailpiece and stopper), remove them carefully from the old lavatory. Put a pail under the sink to catch the water. Once the trap is open, stuff a rag in the drain stub-out to block sewer gases.

Inspect the wall-hung lavatory that is to be replaced. Determine how it has been mounted by checking the underside of the unit at both rear corners. Before unfastening the lavatory, put something under the unit to support it.

If the new lavatory uses the same type of retention method as the old lavatory, mount it the same way, reversing the process used to remove it. However, if retainers are different, remove the existing lavatory and install the new one as per the instructions below.

PROJECT BASICS

Project: Moderate
Estimated Project Time: 3 hours
Start Tips: Turn off the water shutoff valves or the main valve.
Safety Tips: Be careful not to strain your back when picking up and installing the lavatory.
Recommendation: Do-it-Yourself

Fig. 1

INSTRUCTIONS

1) Remove the lavatory
If the lavatory has slots at the bottom of the back, it is supported with a bracket, as shown in Figure 1. The holding bolts hold the brackets securely to the wall. The sink rests on the brackets and is attached by two screws that fit into the slots at the rear corners of the sink. The holding bolts are adjusted for level; release the fixture by removing the sink from the bolts that fit into the slots.

Fig. 2

You may find slots cut into each corner of the rear edge of the lavatory (Fig. 2). The slots intersect with tabs that are connected to a bracket screwed into the wall. This type of unit must be lifted off the bracket.

Fig.

2) Study holes left in the wall
Notice the holes left in the wall by the existing retainer. They are probably spaced 16 inches apart. If the screws that held the retainer to the wall were screwed into the studs, the new retainer can be attached the same way.

However, if the screws do not reach the studs, you will have to use toggle bolts. Be sure they are long and strong enough to support the weight of the new lavatory. To secure a bracket that cannot be attached to the studs using screws, a horizontal framing member can be mortised into the studs (Fig. 4).

3) Determine height Lavatories are normally positioned 31 to 34 inches floor to rim. Be sure to allow for the distance between the slots or lugs of the lavatory and the top of the lavatory rim when deciding upon the height at which the lavatory will be hung. Otherwise, the lavatory will be hung too high.

4) Secure retainer Hold the retainer up to the wall at the correct height, and secure one end of it to the wall.

5) Make retainer level
Place a spirit level across the retainer. An assistant will have to hold the level steady to keep it from slipping as you maneuver the retainer up or down until the level shows that it is straight. At this point, screw the other end of the retainer to the wall. Mount the lavatory and then install the faucet and drain system.