Under-sink Cabinet Fixer-uppers

Ok, this is not as fancy as a media center, but as a solution to the messy, saggy particleboard covered with peeling self-stick paper inside a bathroom sink cabinet it's quick and easy with a Kreg Jig. It took less than half an hour per cabinet, and I wasn't working very fast.

NOTE: If it's moldy and crumbling, you are going to have to replace the bottom shelf, not cover it up. (I'll post that when I get that bath fixed).

The problem with replacing the shelf under a sink is that the base was built into the cabinet and you can't easily insert a new one. Also, the center support in a cabinet prevents you from getting a single piece of material into position. The solution is 2 pieces, held snugly together with pocketholes and optional caulk.

1 – Measure the inside width and depth of the cabinet. If there is an open back, measure inside the wood framing, not to the wall.

2 – Select any combination of MDF shelf widths that will fill the cabinet from front to back.

My bath cabinet was 20", so I bought 10-inch shelving. You could also use a 12 and an 8, or whatever works

3 – Cut the shelf lengths to fit the space side to side. Square cuts, precisely measured!

4 – In the shelf that will be the FRONT piece, drill 3 or 4 pocket holes. One a couple inches from the end and one or two more spaced in the middle.

5 – Align the edges and clamp them.

6 – Insert the pocket screws.

7 – MARK the the rear board with something so you know which is the top side. I used masking tape with "TOP" written on it.

8 – Remove the pocket screws.You have just created alignment holes so you don't have to clamp the boards inside the cabinet.

9 – Clean the inside of the cabinet! You don't have to be hospital sterile, but you don't want dust and glooby stuff in there.

10 – Put the front board in, with the pocket holes on top.

11 – Place the rear board (the one without the pocketholes) into the rear of the sink cabinet, with the holes facing toward you.

12 – (optional) Run a thin line of bathroom caulk along the edge of the rear board.

13 – Align the ends of the boards and screw them together with the pocklet screws.

14 – If you use caulk, wipe off the excess.

15 – Put the white plastic cover plugs into the pocket holes.

16 – (optional) Attach 1/4 round molding to hide the slight gap between cabinet and boards.

    Tah DAH! Clean and cleanable cabinet innards! Picture will follow as soon as I figure out how.


    Oh heck - here's the link:




    Wed, 11/03/2010 - 07:52

    Brilliant!  One of those smacking-the-forehead moments of 'why didn't I think of that?'  it's so simple!

    Tsu Dho Nimh

    Wed, 11/03/2010 - 13:42

    You could also drill on the sides to hold the shelf to the board it is covering up, but gravity works and it's free.


    These bath cabinets were old, but hadn't had major water damage ... the particle board was saggy towards the back more from old age than anything else.

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