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The vanity in our bathroom is about 30 years old and showing it and we often stand in line waiting to use the single sink. Time for an upgrade: two new sinks and vanity.



The bathroom size is on the small side of average – so there is not too much room to work with. The space available for the vanity is about 62 inches. The plan is to remove the existing sink (a single unit with the existing vanity top) and replace it with a laminate top that extends the full 62 inches. The top will be constructed of two layers of 3/4 inch MDF (medium density fiber board) with the plastic laminate glued to the top. The existing frame of the vanity will be kept (we like the cubby-hole on the right for the trash can and step stool) while the doors and drawer-fronts will be replaced. The towel and light fixtures will also be replaced. Finally, everything will get a fresh coat of paint. Plan for 4-6 days for this project.do it yourself, woodworking, shed, sprinkler, irrigation, finish, ch, deck,


1 4×8 MDF 21.95
1 laminate 47.28
8ft 1×2 poplar 4.40
8ft 1×4 select pine 3.65
12ft 1×3 poplar 9.48
1/4" hardboard (2×4) 3.95
2 drawer knobs 3.96
2 door handles 5.98
4 spring-loaded hinges 5.78
1 glue roller 4.98
glue cover 4.98
glue 6.91
2 faucets (w/ pop-up drain) 79.96
2 sinks 158.00
6 braided supply lines (various) 30.84
2 3/8 compression splitter 14.70
various drain pieces 15.21
2 tubes caulk 7.94
light fixture 29.98
fixture kit 29.95
8 40 watt GE Reveal light bulbs 22.72
paint ~20.00
1" and 1-5/8" screws
2 3/8 compression coupling 4.58
4 3/8 tubing 15.88
Total 553.06


  • rotary saw

  • jig saw

  • router w/ flush bit

  • planar or jointer

  • table saw or radial arm saw

  • basin wrench ($9.98)

  • pipe wrench

  • pipe cutter

  • level

  • stud finder

Building the vanity top is not trivial – though it is
straightforward. It consists of cutting the laminate, MDF, trim, and backsplash,
gluing and trimming the laminate, and cutting the holes for the sinks. Plan at
least one full day for this task.

MDF & Laminate

The first task is to cut the MDF to size. The space is
62 inches wide and the vanity top will be 22 inches deep. To provide a smooth gluing
surface for the laminate on the edges, I plan to attach 1×2 poplar to the left
and front edges. Therefore, the MDF needs to be cut to 61.25×21.25.

After careful measurements of the MDF, I first cut the entire sheet to a length of 61.5 inches (the extra 1/4 inch to be removed after the two pieces are secured). The MDF is cut by carefully clamping a straight
edge (I used the 1×4 pine lumber) 1.5 inches from the cut line. The 1.5 inches is the distance from the blade of the circular saw to the edge of the blade guard. I next cut the MDF length-wise at about 22 inches.

With the two pieces of MDF, this is a perfect time to cut
the laminate. The MDF is used as a base to support the laminate. The
laminate is cut in the same manner as the MDF: using a straight edge to
guide the circular saw. The laminate is cut face-down and always a bit
larger than needed – it will be made flush after it is attached.

When cutting laminate, be sure the saw blade strikes the decorated surface first. Otherwise, chips will be produced in the visible surface.

At this point, I applied a liberal amount of glue to both pieces of MDF (after vacuuming the surfaces clean) and pressed them together. Holding them tight with clamps, I drilled several countersinking holes
in one side and then drove 1 inch dry-wall screws. Finally, I carefully measured
and cut the MDF to the correct size of 61.25×21.25 inches.

Trim & Backsplash

To insure a smooth gluing surface on the 1×2 trim, I first
ran the poplar through the planar. I then cut two pieces: one 61.25 inches
for the front and the other 22 inches for the left side – which overlaps
the front.

Furthermore, the 1×4 pine is used for the
backsplash. This was also planed and cut to approximate size.

Poplar was selected for the trim because it is an economical hard wood of
better quality than pine. Select pine was adequate for the backsplash.

At this point, I attached the trim to the MDF assembly.
This was done by applying glue to the trim, clamping it in place, drilling a
countersunk pilot hole, and then driving 1-1/4" #8 wood screws. Use a
utility knife to remove any splinters of wood around the drill holes.

To cut the laminate for the trim and backsplash I
ripped it using my radial arm saw. Two pieces were cut of each of these widths:
1-5/8 inch (trim), 7/8 inch (top of backsplash), and 3-3/4 inch (front of


The next step in building the vanity top is to glue the
laminate to the various pieces of wood. First, I glued the laminate strips to
the front and side trims of the vanity top. This is done by pouring some glue
into a shallow container and applying the glue to both the laminate and the wood
surface. The glue is ready after 10-20 minutes – when it still feels tacky to a
finger pressed on it, yet the glue does not transfer. Be patient – I was anxious
on one piece and had to re-apply the glue and wait again.

In the same manner, I glued the laminate to the front
of the backsplash. If done properly, no clamping should be needed – just
carefully place the laminate on the wood, from one end to the next, and firmly
press it down. You can also buy a rubber roller to apply the pressure (good idea
too – the rough edges of the laminate cut the palm of my hand).

The glue adheres immediately – so the laminate can be
trimmed and/or cut as needed. Using a flush-trim bit in my router, I first
trimmed the laminate glued to the front and sides of the trim.

Then, with the router in a router table, I trimmed the
laminate on the front of the backsplash.

I then glued the thin strips of laminate to the tops of
the backsplash pieces and trimmed them in the router table. However, I was not
careful enough to keep the backsplash square with the table and bit into the
surface of the laminate a bit. I tried to hide it with a blue marker – but it
did not help. So, I ripped about 3/8 inch off, re-applied the laminate
strip to the new top, and more carefully trimmed it with the router. (This
turned out to be serendipitous as the new height of the backsplash would fit
perfectly between the bathroom mirror and the vanity top.)


Finally, the holes can be cut into the vanity top. A template was provided with the sinks. I positioned the holes about 7 inches from the edge (I wanted 5 but the drain of one sink would interfere with one of the
supply lines) and 3 inches from the front. I accidentally measured the 3 inches from the front of the vanity top to the edge of the template – as opposed to the edge of the hole. So, the sink actually ended up being about 4 inches from the front – no problem.

After positioning the template, I traced the hole. Then I drilled a starter hole and used the jig saw to cut the hole. Since the jig saw does the cutting on the up-stroke, the laminate was face-down again. This was a
very slow job. After cutting the first hole, I test-fit the sink. It as all good.

Note: One thing that I should have done at this point is to paint the
remaining exposed MDF with a sealing primer or shellac. MDF has a high affinity
for water and the humidity in a bathroom can ruin the entire project and cause
the laminate to come loose. I was made aware of this near the end of the project and
tried my best to paint it from below.

Installing the new vanity top built above
requires disconnection of the existing plumbing, removal of the existing
vanity top, installation of the new vanity top, installation of the sinks and
faucets, and connection of the new plumbing. This should have taken 1 full day –
but some problems with the plumbing stretched it into a bit more than 2 full

Remove the old

To disconnect the old plumbing I first turned off the
water supply valves under the sink and used the basin wrench to disconnect the
supply lines from the faucet. If you don’t have a basin wrench, get one – it is
well worth the $10 and is much easier than shimmying a box wrench in the small
space behind the sink.

Next, I disconnected the drainage pipes from the wall
and the bottom of the sink. If you can’t loosen them with your hands, use a pipe
wrench. Use a container to catch the water (and slime) in the pipes and be sure
to stuff a cloth in the drain pipe to prevent sewer gases from entering the
room. The old vanity top was not secured to the vanity base, so I was able to
remove it at this point.

(The holes in the sheet rock were cut last winter to help
prevent the pipes from freezing in the -20‚°F weather.)

I then removed the supply lines from the valves and
attached the splitters to the valves.

NOTE: Never tighten a nut without anchoring the
fitting with another wrench. For example, the splitters were tightened with a
5/8" wrench while vise grips secured the valve for leverage. This relieved
the pipes from stress.

I ran into a problem with these splitters. The base and top are secured with a threaded connection. As I
tightened the nut onto the valve, this connection came loose and caused a leak (I needed the splitter to point in a certain direction). To overcome this, I took the assembly apart with a hex wrench (inset) and wrapped the
threads in Teflon tape (shown on the other threads).

New Vanity Top & Sinks

I could not do any more plumbing at this point without
the sinks in place as my initial plan was to use copper tubing and compression
fittings (more on this below). So, using a level and stud finder, I screwed
cleats into the wall to the right of the vanity base. These provide support for
the vanity top.

I am finally ready to install the vanity top – probably
the simplest of tasks. After putting it in place, I secured it to the vanity
base and cleats with 1 inch angle brackets and screws. To install the sinks,
first attach the faucets as it is easier to do with full access to the mounting
nuts. Next, run a bead of caulk/adhesive around the rim of the sink and
carefully lower the sink into place. I used my finger to remove excess caulk and
then a damp cloth for additional cleanup.

Plumbing: Supply Lines

With the sinks installed, I am ready to connect the supply
lines from the faucets to the splitters attached to the supply valves. To
do so, I first drilled two holes in the side of the vanity base and
connected two 30 inch copper tubes to the faucet on the right.

I then connected the supply lines on the left to the other
sink. These were more difficult to align in the correct position due to
the shorter distance to work with. I bent one of them too far ruined it. I
had to run to the local hardware store to buy a replacement at $8.99.


The tubes to the sink on the right were not long enough to
reach the supply valves. So, I needed to install a coupling joint. I
attached the joint to the tube, inserted another tube into the splitter,
and marked where I would need to cut it.

After carefully tightening everything down (don’t forget to
use an anchor) I turned the water supply on and inspected for weeps (small
leaks of water). It did not take long. They were everywhere.

I went to ask Mike, my neighbor, for advice. He came over to take a
look and said, "For future reference, use the steel braided hose with
gasket seals rather than copper tubes and compression fittings." I
explained that the guy at Home Depot said I had to use compression
fittings since I had the splitter. Mike mentioned they should be
compatible… Oh, well, Duh! of course they would be. Simply remove the
compression nut and attach the braided hose! Why didn’t I think of that
before? I like to blame the guy at Home Depot for the bad information, the
$30 in wasted supplies, and more than a day’s worth of work.

So, it was back to Home Depot to buy the braided supply
lines. They come in various lengths of 12-30 inches and with various
connections. I purchased two 16 inch and two 30 inch lines with a
1/2" female faucet connector on one end and a 3/8" supply
connector on the other end. Since 30 inches was still not long enough to
reach the supply valves from the right sink, I also purchased two 16 inch
lines with a 3/8" supply connector on one end and a 3/8"
compression fitting on the other. I simply removed the compression nut and
attached the 3/8" supply connector from the 30 inch line

The flexible braided supply lines worked like a charm.
The gaskets in the connections provide a much better seal (which, by the way,
make the use of the Teflon tape shown in the photo redundant). There was only
one small leak remaining. A small weep had formed at the base of the splitter on
the cold-water supply valve. After numerous attempts to get it to stop, we
concluded that the valve must be faulty. Mike helped me replace it which
involved shutting off the water supply in the house, relieving the pressure in
the pipes, removing the old valve, and soldering on a new one. After turning
everything on, everything was as dry as the Sahara.

Plumbing: Drainage

With the water supply finished, it is time to connect the drainage pipes. Since there are now two sinks there is a little bit of a challenge to get the two sinks to drain into the same pipe. My plan is to install a 90‚° bend at the drain of the right sink and connect with a T-joint below the left sink which will then connect to the J-tube (or P-trap).

The first step is to install the pop-up drains in the sinks. This is done by first applying a bead of plumber’s putty (a non-hardening silicon-based putty) around the opening in the bottom of the sink.

Next, insert the pop-up drain body up through the bottom of the sink
and screw on the top flange (the shiny part visible in the bottom of the
sink). Finally, tighten the nut on the bottom of the drain body.

I originally wanted the pipe connecting the 90‚° bend with the T-joint to be low enough to not interfere with the drawers. However, this would force the T-joint to be below the drainage pipe in the wall – which would not work. In fact, to get it high enough, I had to cut a few inches off the bottom of the pop-up drain. (Since this interferes with the top drawer, it was cut short to make room for the pipe.)

A slip joint is used in non-pressure drainage systems. As shown here, it consists of a nut, a gasket, and the fitting. First, place the nut on the pipe to be connected. Second, slide the gasket on the pipe.
Third, insert the pipe into the fitting. Finally, tighten the nut down by
hand – no tools. If you end up with leaks in a slip joint, simply apply
some putty around the gasket – petroleum jelly even works.

Typically, bathroom drainage is 1-1/4" while 1-1/2" is found
in the kitchen. The 90‚° bend and the T-joint were both 1-1/2".
Therefore, I needed special gaskets which transfer from one size to the

Using a 1-1/2" hole saw, I cut a hole in the side of the vanity. I inserted a 1-1/4" pipe extension through the hole and connected it to the 90‚° bend attached to the pop-up drain of the right sink. I cut the hole such that the pipe would be on a slight incline to facilitate drainage.

Another pipe extension was connected to the first. (The hole on the bottom is the first location I used before I realized it would not drain – as mentioned above.)

The second pipe extension from above is then connected to the T-joint with a shorter pipe extension (cut with a handsaw). The T-joint (connected to the pop-up drain of the left sink), is then joined to the J-tube with another short section of pipe.

The J-tube is then connected to the drainage pipe in the wall using the
original nut and a new gasket. (Don’t forget to remove the tissue plugging
the pipe!)

The final step is to connect the pop-up drain handles
and test it. The drain is a bit noisy, but works great.

The plan is to make Shaker-style paneled-doors (square
edges – no contour router work). The panels and drawer fronts will look like
wanes coating. Plan for a day or so to cut, assemble, and paint the doors and
drawer fronts.


The rails (horizontal) and stiles (vertical) for the doors are to made from 1×3 poplar. I planed the front and back surfaces once and then planed the edges down to a width of 2-1/8 inches. The size of each door is
20 inches high by 11 inches wide. Planning for a tongue-and-groove joint of 3/8", I cut the stiles to 20 inches and the rails to 7.5 inches.

With the router in the router table, I created the grooves in one edge of all either pieces. The groove needs to be 1/4" thick. Special bits are available to do this and I would have used one had I
measured it first. The bit I have cuts a groove 1/2" deep but it was too late: I had to stick with 3/8". So, I used a router bit I had laying around which is used for a biscuit-jointer attachment. The two boards in the foreground are clamped to the table to produce a cut depth of exactly 3/8".

Once the grooves are cut, I create the tongue on the
ends of the rails. This is done by using the same bit to remove 3/8" from
the end just above and just below the groove on the adjacent edge.

The panels are cut from 1/4" hardboard. Using a
V-groove bit in the router and a simple jig to create the wanes coating effect.

To assemble the doors, I placed a bead of glue in the
grooves, inserted the rails into one of the stiles, slid the panel in, and
attached the other stile. Finally, I clamped it all together.

The drawer fronts were cut from MDF. I again used the
V-groove router bit to produce the wanes coating effect.

Once the glue was dry, I primed everything with a
shellac-based primer. This was followed with two coats of semi-gloss interior


Installation of the drawer fronts is trivial: simply
remove the old ones and add the new. To install the doors, I first attached the
hinges to the doors. I then determined the appropriate location (one edge is at
the very center of the opening) on the vanity base for one of the doors and
attached the top hinge to the vanity base with a single screw. Then, using a
level, I made sure the far edge of the door was perfectly vertical and then
attached the bottom hinge with a screw. I than added the other two screws and
repeated the procedure with the other door.

The finishing touches on the project include painting,
fixtures, and the backsplash. This can take about a day as well.

The backsplash is attached to the wall by applying a
generous amount of caulk/adhesive to the back and then sealing the joints with
additional caulk (I used clear caulk for the joints).

I also glued some of the laminate to a piece of MDF to
use as a skirt under the open portion of the vanity top. It helps to hide the
underside of the sink and other plumbing. I choose a height of about 6 inches to
be even with the facade on the other portion of the vanity base.

Finally, the walls were painted a nice blue to match
the vanity top, the towel fixtures were replaced to match the faucets and a new,
larger light fixture replaced the old (again, to match everything else).
Finished for now, but what about that old stinky tub…



Another Vanity Idea:


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