How I made Built-in IKEA Bookshelves with a Window Seat for under $350

IKEA window seat hack with BILLY bookcases and TV unit as a bench turning it into a reading nook
Photo Credit: Theresa Novak

We wanted built-in bookshelves, and I have always loved the idea of a cozy window seat to curl up in while reading a book.

The wall we wanted to build the shelves on was 158″ wide, with a slightly off-center window. We decided to use the BENNO TV Bench as the window seat.

Two 31″ wide bookcases on each side would be too wide, and one 31″ and one 15″ would be too narrow.

How we made our IKEA window seat hack with bookshelves

Materials:

  • BILLY bookcase
  • BENNO TV Bench (The BENNO TV bench is discontinued, you can try this hack with a BESTÅ TV bench)

1. Hacking the BILLY bookcases

IKEA window seat hack with BILLY bookshelves and TV unit as a bench turning it into a reading nook
Photo Credit: Theresa Novak

Due to the space we had, we had to cut two 31″ BILLY bookcases down to size and then drill our own holes in the end of the shelf that we cut so that we could use the adjustable shelf pegs.

We decided not to use the backing board for the bookcases; we filled the track in with joint compound.

Paint color matching the BILLY

I brought a shelf to Home Depot, and they matched the paint color very well–although I got semi-gloss, and the IKEA finish has slightly less of a sheen, but the line for the track is invisible after being filled and painted.

We removed the baseboard trim behind the bookcases and on the side. We measured from the rear wall to where the studs were on the wall.

Securing the bookcases to the wall

Once the bookcases were in place, we measured from the rear wall to where we knew the studs were and screwed the bookcases to the studs.

We then screwed the sides of the abutting shelves to each other. Then my husband screwed ferring strips to the beam above the shelves and into the top of the shelves, so they are securely attached at the top and sides.

2. Turning the TV unit into a Bench

We decided the top of the BENNO TV Bench was not deep enough, so we made a brace for the wall, screwing a 2X4 into the beam. We bought a 24 x 48 piece of alder, which we sanded and stained, then affixed to the brace we made on the wall, as well as the top of the BENNO.

3. Finishing touches to our window seat hack

Finally, we nailed 2″ lattice to cover the space between where the bookcases meet. We replaced the baseboard and picked out nice crown molding for the top of the bookcases.

We filled the nail holes and painted everything with the paint we had custom mixed to match the shelf we brought to the home improvement store. We bought some drawer pulls for the front of the Benno so it looks less modern and more traditional.

We love our new built-in bookshelves with a bench. The window seat has become a favorite reading nook!

~ by Theresa Novak