Cainz completes its takeover of building-materials trader Sonitec

Cainz Corporation said on October 19 that it has completed the acquisition of all issued shares of Sonitec Co., Ltd., a Tokyo-based trader of building materials for wooden-house construction, finalising a deal whose share purchase agreement the two companies had signed on October 6. The seller was NMC No. 4 Investment Limited Partnership, an investment vehicle backed by Nippon Mirai Capital Co., Ltd.

Sonitec was founded in July 1967 and is headquartered in Nihonbashi Honmachi, Chuo-ku, with capital of ¥66.4 million and 266 employees, including part-time and dispatch staff, as of March 2026, according to Cainz. Its business is the comprehensive sale of subsidiary building materials for wooden-house construction, run through offices and distribution centres stretching from Tohoku to Kyushu, serving housemakers and builders with estimation services and delivery scheduled by house and by construction stage. Sonitec's chief executive, Tokuya Ikeguchi, remains in place; financial terms of the acquisition were not disclosed.

Cainz said the purpose of the deal is to strengthen Sonitec's procurement, estimation, ordering and logistics capability by applying its own digital expertise, building what it called "a unique supply chain that contributes to improved construction productivity for building professionals," spanning new construction through renovation. Sonitec becomes one company within the Cainz group, the company said. The acquisition reads as vertical integration rather than diversification: Cainz is already Japan's largest home-improvement chain by store count, and a building-materials trader with its own distribution network gives Cainz a direct line into the professional-contractor side of the renovation market that its retail floors alone don't reach -- the same logic behind its recent run of small urban renovation-focused shops.