Hidden Storage Step

Introduction
Here is a project a friend asked me to help build. The design was to have a compartment in the stairs with access by lifting the tread, simple enough. After reviewing his idea, I suggested we install it on the bottom step and add a second compartment below the first compartment, surely if they found the first compartment who will look for a second? They would be proud and pat themself on the back after finding the first compartment.

This instructable is building a hidden compartment inside of a hidden compartment.

Next Tools and Supplies

Tools:
Screwdriver,
Drill & Bits,
Tape,
Pencil,
Combination Square,
Saw and
Hammer.

Supplies:
2x6x1’ Pine Board,
1x8x3’ Pine Board,
Floating Floorboard (or other thin material),
Cabinet Latch,
Cable Staple,
2 in Finish Nails,
4d (Penny) Wood Nails and
3 Plastic Boxes.

Next 1st Compartments

Here is where you will add bottoms for your divided hidden compartments. We used the Floating Flooring Board, use or buy a thin board to conserve on space.

1) Remove Step,
2) Measure inside bottoms (Left and Right),
3) Cut inside bottoms (Left and Right) and insert.

Next 2nd Compartment

Here is where you will create you hidden compartment accessible through the bottom of the first hidden compartment. We used the Floating Flooring Board, use or buy a thin board to conserve on space.

1) Measure between Landing Joist and Landing Frame,
2) Cut 2nd Compartment bottom,
3) Hammer Cable Staples in the Landing Frame and Landing Joist to support 2nd Compartment bottom,
4) Insert Box and add False top cover to hide Box.

Next Back Board

Here is where you will add your back board. The back board is from the 1x8x3’ Pine Board and the triangle fillers are from the 2x6x1' Pine Board.

1) Measure inside between the outer Stair Stringers (Left and Right) and cut the 1x8x3' Pine Board,
2) Measure inside between Middle Stair Stringer and outer Stair Stringers for the notch,
3) Cut a notch in the Back Board at the "middle" so the Back Board will be flush with the frame of the landing,
4) Drill a pilot hole and nail the Back Board to the Middle Stringer,
5) Cut the triangle filler out of the 2x6x1' Pine Board to cover the gap between the Back Board and the Stringers (Left and Right),
6) Drill a pilot hole and Nail the triangle filler to the Stringers (Left and Right) and the Back Board.

Next Lock

Here is where you will add a lock. We chose a simple Cabinet Latch after deciding against a magnetic or bar locking mechanism.

Align and attach the Cabinet Latch to the riser and step.

Next Observations & Summary

Observations
This is a low-cost, no new parts build, everything was resourced from what we had on hand. While this build is a retrofit in a place not frequently visited, most sizes (measurements) are not square, e.g. the "middle" riser is not in the middle, there is more space on the right side than the left side. The landing is not square with the stairs or level with the basement floor. There were adjustments made along the way to compensate to make this work.

Your compartments will vary in size, but persevere.

Summary
I am satisfied with the results especially having to make adjustments due to the quality of the original stairs and landing installation.