You've probably seen them on business cards, T-shirts, brochures, and other marketing materials. QR (quick response) codes are two-dimensional bar codes that take users to an online address via smartphone, tablet computer, or other device programmed to read them. Pioneered in Japan, QR codes are slowly catching on with U.S. merchants.

A recent survey of 700 Boston-area stores by mobile tech researcher Nellymoser found that 23 store brands — 7.2% of stores visited — had incorporated QR codes into their marketing.

EXPERIMENTAL STAGE But only a few home improvement companies have experimented with QR codes, and the results have been mixed.

Brian Elias, president of 1-800-hansons, a Michigan window, siding, and roofing company, says Hansons created a landing page for a QR code, but so far the company “hasn't had much luck” in generating responses via the page. “When [homeowners] are researching a project,” Elias says, “[it] seems they're sitting down somewhere rather than being on their phone.” Renaissance Conservatories, in Leola, Pa., included a QR code on a recent postcard mailer. P.J. Fitzpatrick, in Newark, Del., flashes a QR code in an electronic ad for its repair services posted in the Philadelphia public transit system.

ANOTHER TOOL IN THE TOOLBOX Last fall, A-Team Home Improvements, in Alexandria, La., had its webmaster, Vickie Romero, create a QR code taking viewers to the company's website. About 14% of A-Team site traffic now originates from mobile users, and Romero is in the process of creating a promo page advertising current discounts so homeowners can scan and show coupons to salespeople.

Romero notes that few home improvement companies use QR codes but that the code is “a great tool to have in your marketing toolbox,” especially as smartphone use grows and more people “use them as their main source of connecting to the Internet.”