How do I remove the mirror that the original contractors put in my
bathroom. It seems to be glued on and there is a support shelf under it.

 

You can search this forum for previous posts on this topic. Removing a mirror is one of the most frequent questions asked here. If the mirror is glued on, expect damaged dry wall and having to do repairs.

Cover the vanity to protect it. Put on goggles to protect you. You can cover a hammer with an old towel and break the mirror and pry off pieces with pry bar. Another option is to use a heat gun to soft adhesive and a pry bar to lift mirror. Work as safely as you can. I have also read that you can take a piano wire and slip it under the edge of the mirror and saw up and down through the adhesive. With luck, the contractor applied the adhesive in blobs rather than all over and it will make for easier removal. Removing a glued on mirror is not an easy task for anyone

 

The hammer doesn't need protection .however if you cover the mirror with a big drop cloth, you'll be protected from the flying glass chips.
The wire method is generally used to remove and save smaller mirrors. You'll still have the same amount of drwall damage as the mastic will still need to be removed from the wall. The wire tends to heat up quick which causes it to snap and makes a long effort for a large mirror...The ledge underneath will also prevent access. With all said and done,,,,The quickest method I have found is too:
Lay down heavy drop cloths to protect the vanity.
Score around the perimeter of the mirror with a utility knife to minimize drywall paper damage.
Score the mirror with a glass cutter every 6 inches on the vertical
Run duct tape every 10 inches on the horizontal
Place a slotted screwdriver behind the score line at the top and gently tape with a hammer to run the glass.
tap the front to continue the score line and remove each piece as you can. Eventually you will need to use a wide chizzel bevel face down to remove some sections.
As carefully as you can remove the paper of the drywall with adhesive still attached.

or

Cover with a drop cloth that drapes to the ground or vanity and hammer for a few minutes...Then remove by section.....

With all said and done it takes about 15 minutes to clear the wall and 30 to clean it up........WEAR GLOVES

Skim coat, sand, prime and paint........1 hr plus......

 

Those are the best bathroom mirror tips I've read yet, Stephen. I saved them to my Favorites. Thanks!

Best regards,