Before and after: This BILLY bookcase is now a bespoke built-in with a minimalist aesthetic

This BILLY has a new life, in the shape of a boutique built-in – kissed with botanics, books, and beautiful brassy tones

IKEA BILLY bookcase hack close details
(Image credit: Kaari Sommer)

Our love for a certain Swedish powerhouse is far from subtle, especially when it comes to stylish flatpack makeovers. And our latest IKEA BILLY crush is worthy of all the excitement – and more.

While BILLY is already one good-looking bookshelf, designer Kaari Sommer took the staple another step further and turned the unit into a beautiful built-in – complete with brass-hued swing lighting and an array of art books – because this is a BILLY, after all. 

Her IKEA hack is among our most favorite to date – combining everything we admire about the Swedish chain with a boutique hotel aesthetic. Here, Kaari walks you through the design process.

IKEA BILLY – before the hack

IKEA BILLY lifestyle shot

BILLY styled by IKEA

(Image credit: IKEA)

After building and moving into their home, Kaari and her husband wanted to create a wall of built-in bookshelves in their den. So, they turned to IKEA – who made it possible. 

‘I got a bid from the cabinet shop that did our kitchen. It was outrageous and definitely not in the budget. I had heard of an IKEA Billy Bookcase hack being done before, so I got on Google, formulated my plan, filled my husband in, and we got to work,’ Kaari shares. 

In her blog (opens in new tab), Kaari outlined the intricacies of the design process, beginning firstly with purchasing 4 BILLY (opens in new tab) bookcases. They also picked up a BILLY height extension (opens in new tab) and the OXBERG (opens in new tab) doors. Kaari then bought MDF – and Benjamin Moore’s Simply White (opens in new tab) for the trim. 

Kaari then designed a wooden platform and was careful to evenly space the BILLY units against the wall. Crucially, the space between the left bookcase and the wall and the right bookcase and the wall remained consistent – along with the distance between each shelf.

IKEA BILLY – after the hack

IKEA BILLY

(Image credit: Kaari Sommer)

Once the four shelves were in place, Kaari added trim to the top and sides of the bookcases. After completing the structure, she used wood filler and sanded the units – ensuring they appeared as though they were originally one bespoke piece. The result is the modern living room idea your home deserves. 

Finally, Kaari filled the famous IKEA holes to remove its flatpack origins and revisited Benjamin Moore’s Simply White, which further removed the units from their heritage. After the paint dried, she added the statement brass handles before filling the new furnishing with equally sophisticated books, pottery, and some curated greenery. 

IKEA BILLY hack

(Image credit: Kaari Sommer)

If you’re looking to mirror this modern home decor idea in your home, Kaari’s blog has an in-depth tutorial, while her Instagram (opens in new tab) has footage of the makeover. Let the BILLY transformation projects begin. 

Megan is a News Writer across Future Plc’s homes titles, including Livingetc and Homes & Gardens. As a News Writer, she often focuses on micro-trends, wellbeing, celebrity-focused pieces, and everything IKEA. 


Before joining Future, Megan worked as a News Explainer at The Telegraph, following her MA in International Journalism at the University of Leeds. During her BA in English Literature and Creative Writing, she gained writing experience in the US while studying in New York. Megan also focused on travel writing during her time living in Paris, where she produced content for a French travel site. She currently lives in London with her antique typewriter and expansive collection of houseplants.