Built-in shelves can be created easily by attaching the shelving unit you build directly to the wall. This will give the appearance that the shelves have been incorporated more fully into the wall and the room's décor. To create a more high-end look, use only hardwood. Keep the wood's natural appearance, rather than painting it, to make the shelves appear even more high-end. With the right tools, this project can be complete within a day.
Pry off pieces of the base trim to give you room to attach the shelves directly to the wall. This is what will give you that high-end built-in look.
Cut four pieces of 2-by-4s to length with a miter saw to create the bottom frame for the shelves. Two long pieces match the length of the shelves, while two short pieces match the depth. Attach the pieces to each other with a power nailer.
Attach the frame directly to the wall using the power nailer.
Purchase boards that are at least one inch thick to create the sides of your shelving unit. For a more high-end look, be sure the panels bring the shelving unit almost to the top of the ceiling with just enough space leftover for the top piece. Measure out where the shelves will be installed and drill at least two holes at each end of the lines, placing them on top of each other while drilling so that the holes with be level. These will be peg holes to install the shelves.
Secure a board to the top of the two side panels with carpentry glue and then increase the hold with your power nailer. Then, place the side panels on top of the bottom frame and nail them to the frame to complete the entire shelving frame.
Add another board to the bottom frame and nail it in place to conceal the frame.
Attach a decorative trim around the top and bottom of the shelving unit. Use the trim that you removed from your wall along the front of the shelf to make it look more built-in. If you need extra trim, you can use your miter saw to cut it from an extra piece of lumber.
Insert pegs into the pre-drilled holes along the inside of the side panels. Cut shelves to fit with your miter saw and set them on top of the pegs.
Cover all exposed nails on the built-in shelves with putty to conceal them and complete the high-end look of the shelves.