Making a Christmas faux fireplace from two boxes that --standing upright-- are the width of the fireplace you want to make.
Step 1: Starting Point
With two large boxes and matching covers --these were from desks shipped in pieces.
Removed staples and stickers where needed. Taped the two bottoms side by side to get a rough idea of the total. We cut a section about 8 inches in width from one of the box tops, opening up one corner for a little extra length, then taping it to fit on top as a mantlepiece.
At this point the inside is taped at top and bottom only with a similar piece of duct tape on the outside, top and bottom.
Step 2: Cutting the Interior Out and Making a Back for the Inside
We cut from the inside of the two box bottoms:
Right side: six inches from the top going outward from the center, leaving about six inches from the edge. Repeat on the bottom, outward from the center. To make it easier to bend, I scored a vertical line down at the six inch mark and again six inches (or so) and at the next six inch point cut off the remainder. The three panels held only by one side of the cardboard folded into a column which was then taped to the right edge for structure.
Left side repeat, cutting to about six inches from the edge, then scoring down along that line, again scoring six inches out, then cutting at six inches further to make a column on that side.
By purest of luck the top of one of the boxes FIT like it was made to go there from the back side. We taped that into position, giving the whole thing a good solid structure.
The mantle just sits on top, sticking forward a little to give depth. (Taped into position with duct tape)
Step 3: Base Coat
One can of white spray paint later ( well two cans that had already been partly used, one of them off white) to hide the black duct tape and writing on the boxes. I used an old tarp to keep spray off from killing the grass.
Step 4: Bricks
We made two brick templates from some thin spongy packing material hot glued to cardboard rectangles cut from scraps. Mixed a paper plate of acrylic paint with red, darker red, and whatever we could find that approximated red from the crafting stuff at the house. The offset pattern and irregularity of the sponge worked out well. Not saying both sides are exact or anything.
My daughter started this whole mess so she got the drudge work of painting the interior black. I had thought she was going to leave the mantle and bottom edge white, but she managed to pull out wood grain on those that I forgot to take a picture of but can be seen in the final assembly.
The wood grain is a light brown coating (acrylic) with darker lines added while wet so they wash a little. It worked.
Step 5: Logs
While she was waiting on things to dry I added some rolled up scraps to serve as logs, glue gun to hold them rolled. Here shown I was seeing how a set of Poinciana (solid red, no blink) lights worked as embers in the fire. The logs are glue gunned into position at the angle.
When she was adding the wood grain, she also painted in some wood grain on the visible log pieces.
Tried to make some waxpaper flames with acrylic, and a cutout of fire. Doesn't really sell the idea --so might skip that. (It was me, I take responsibility for the fail that is the paper flame)
Add some stockings, lights and things on the mantle. Bow on front.
If there is any weight involved, you may want to fasten the "fireplace" to the wall. In our case, we used 3M hangers on the light strings and used the cord of the lights to rope the whole thing to the wall.
My daughter gets all the credit for the idea, I only 'helped' with execution and providing of the junk filled garage and some paints. ;)