Remove current mailbox and post. If the post is set in concrete, that too must be dug up and removed before proceeding. Clear away all dirt and debris from the site. Mark off a 2’ square where the mailbox will be built. Excavate the area to a depth of 8”. Use tamper to level and compact soil. Add pea gravel to a height of 2” then compact and level with tamper.
Mix fast-drying cement according to manufacturer's directions to create the mailbox footer. Once the cement reaches the proper oatmeal consistency, pour on top of pea gravel until the hole is filled to ground level. Smooth and level the cement pad using a trowel and carpenter’s level. Allow cement to cure for 24-48 hours, depending on conditions.
The mailbox is built by laying courses of bricks against an interior core of stacked cement blocks. Position two 8” x 8” x 16” concrete blocks side by side on top of the mailbox footer, making sure they are centered and square. Mark their position in the footing by outlining them with a trowel or pencil. Remove the blocks. Prepare premixed mortar according to manufacturer's directions. Lay a generous layer of mortar along the marked lines where the blocks will sit, making sure there enough to support the blocks. Place the blocks onto the mortar (Image 1), pressing into place, making sure they are square, plumb and level.
Apply a layer of mortar on top of the first row of cement blocks. Press two cement blocks into the mortar bed, making sure to run this second course perpendicular to the first (Image 2). Make sure they are square, plumb and level.
Apply a generous layer of mortar on the footing around the base of the foundation (Image 1). Lay the first brick by pressing it gently into the mortar. Apply a layer of mortar to one end of the next brick before butting it against the first and pressing it into the mortar (Image 2). Remove excess mortar. Continue working in this fashion until the first course has been laid around the entire base of the foundation. Check to make sure the course is square, plumb and level, adjusting a brick by tapping with trowel handle.
For the next level, apply mortar to the top of the previous course. Lay the first brick by pressing it gently into the mortar, making sure to stagger the joints. Apply a layer of mortar to one end of the next brick before butting it against the first and pressing it into the mortar. Remove excess mortar. Continue working in this fashion until the second course has been laid around the entire base of the foundation. Check to make sure this course is square, plumb and level.
Continue this process until six courses of brick are laid, which will bring the bricks to the same height as the cement foundation blocks. After the final course is set and before the mortar has dried, “strike” the joints with a jointer to create the familiar concave depression in the mortar.
For an interesting pattern variation, replace the fourth, fifth and sixth courses of bricks with one "soldier" course (bricks placed on end). Start this course approximately 1/2" in from the edge of the third row so that the edge of the underlying brick is exposed, leaving a “reveal" (Image 3).
Before beginning the next course, lay metal strap anchors across the already laid bricks and cement blocks to secure the wall and foundation together (Image 1). Apply a generous layer of mortar on top of the previous row of cement blocks. Press two cement blocks into the mortar bed, making sure to run this third course perpendicular to the second. Check for square, plumb and level.
Apply a generous layer of mortar on the previous course of bricks and continue to lay bricks in normal fashion around entire foundation. Continue adding courses until the height of the bricks matches that of the cement block foundation. Check to make sure that each course is square, plumb and level.
After the final course is set and before the mortar has dried, strike the joints with a jointer.
If the height of the third and final cement block foundation is not as high as you’d like the mailbox, add additional levels using cement blocks and bricks as in previous steps (Image 2).
Add a large bed of mortar to secure the mailbox, treating the box as if it were a large brick. Press the mailbox into the mortar, positioning it far enough past the brick base so the door has room to open. Install a “soldier” course of bricks all around the mailbox, just in from the edge of the brick base. Fill in the gaps between the mailbox and the bricks with mortar.
Install two more horizontal levels of bricks above the mailbox. For a decorative finish, "step up" the remaining courses by extending a course of bricks over the edge of the previous layer to create a reveal, then moving each subsequent layer a little in from the edge.
After the final course is set and before the mortar has dried, strike the joints with a jointer. Wait a few hours for the mortar to dry and then use a stiff-bristle brush to remove loose particles from the mailbox.
To add an optional light fixture to the top of the brick mailbox, you'll need to run an outdoor electrical cable underground from main breaker box up through the interior of the brick structure. Hire an electrician to connect the cable to the breaker box.