Wall hung sink anchoring

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by jadnashua, Feb 3, 2007.

  1. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Sep 2, 2004
    Retired Systems engineer for defense industry.
    New England
    I'm going to be installing a wall-hung vanity sink in a few weeks. The old one now removed had some clips on the wall - only one screw actually went into a stud or blocking. The position of the new sink's screws don't line up with any stud or blocking. It's plaster on gypsum board from the early 50's (no lath).

    Would you tear the wall up and put in blocking? or just rely on say toggle or molly bolts? the sink is 21.5" wide and 16.5" deep. The drawing shows two bolts holding it to the wall (I don't have it or the instructions, yet).
  2. geniescience

    geniescience Homeowner

    Nov 27, 2005
    humid summers hot, humid winters cold
    2 bolts in plaster? No.


    A 17" lever from the wall is small, but still far too big, even if your sink has several inches depth, which brace it too.

    On an average day, nobody is going to put their weight on the sink. One day it will happen. Someone will sit, lean, fall or step up onto the sink. From that day forward the wall support "system" will deteriorate visibly. The drywall hole, or the drywall itself, will deteriorate, no matter how solid the butterfly / toggle / bolts feel on Day 1. The P trap and plumbing will give it some more solidity too, but that won't be the answer either, i.m.o. The supply plumbing will help it hang in mid-air if the whole assembly ever gets too loose.

    If you put in blocking, the repair will be easy since most of the opening is already hidden by the sink.

    What is on the sides? Empty space?

    You could bolt a cleat into the studs, and drop the other cleat (bolted to sink) into it. French Cleat.
    Used for mirrors and heavy things. I might make it out of metal. I might cut away the drywall to bolt in to the studs directly -- this will bring the sink closer to the wall.

    No matter what you do, it's a lot of calculating and thinking, and I can understand why the average homebuilder just relies on boxes that use gravity to stand on the floor. I still have to install two wall-hung sinks in my neverending bathroom renovations.

  3. Sponsor

    Sponsor Paid Advertisement

  4. Racer814

    Racer814 New Member

    Dec 24, 2006
    you can cut a hole in the sheetrock behing the basin....not much wider than a 2x4 so that it will be hidden....measure stud to stud behind it.....screw one side of the 2x4 to the stud if there is one behind it and screw the other end to adjacent stud by angling a long drywall screw through the sheetrock and into the 2x4 block and on into the stud....do the same thing on the other side of the blocking if there isn't a stud behind the basin........all you have to do then is mud over the drywall screws..I've done this numerous times on pedestals that were installed with no supports

    I had a service call on one last summer that was sitting 6" off the wall..you could bump it and it would wobble....the homeowner didn't even know any better:eek: ....we used this same method to fix his and he was:D
    Last edited: Feb 3, 2007
  5. norcal1

    norcal1 Plumber/Owner

    Jan 24, 2005
    If you can't brace it well, then just put in a pedestal sink.

    I have an elderly lady client who lost her balance and leaned on her wall mount sink (NOT installed by me) and the thing came crashing down...she was very lucky to not be injured. And, she was very lucky that there was slack in the stainless steel flex lines or water could have been spraying everywhere.

    Needless to say, she asked me to install a small vanity setup. :)
  6. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Sep 2, 2004
    Retired Systems engineer for defense industry.
    New England
    I think I'll give the people at www.wingits.com a call to see if they think a pair of their fasteners would work. They are designed to install safety grab bars and other things. I'll report back what they say. These fasteners are similar to a molly bolt, but much bigger in diameter and more fingers.

    Getting the wall to look good if I cut it out and reinforce it will be a pain - it has approximately 3/8" of plaster on top of plaster board (not really drywall - its strips of about 2' high drywall looking stuff, but is finished like drywall on the long edge - I'd never seen any before this house).
  7. TedL

    TedL New Member

    Sep 17, 2006
    NY Capital District
    You have lath...gypsum lath. I had it in my first house, 1930's vintage.
Similar Threads: Wall hung
Forum Title Date
Plumbing Forum, Professional & DIY Advice Navien wall hung boiler question Mar 22, 2018
Plumbing Forum, Professional & DIY Advice Replacing/relocating boiler with wall hung boiler Jan 23, 2018
Plumbing Forum, Professional & DIY Advice Code for wall hung boiler in bedroom Feb 17, 2017
Plumbing Forum, Professional & DIY Advice Back to back wall hung toilets Mar 24, 2016
Plumbing Forum, Professional & DIY Advice Timber Frame Constraint and Wall-Hung Toilet Question Sep 14, 2015

Share This Page