Gemini Gives No Source in 82.2% of Home Improvement Answers vs 2.2% for ChatGPT

A homeowner asks an AI assistant whether to insulate the attic before winter or when to plant a new lawn. On ChatGPT, the sources listed under the answer look like a reading list from a land-grant university: the Department of Energy, the EPA, Iowa State, NC State. On Gemini, more than eight times in ten there are no sources at all.

Contractors, retailers and home publishers compete for citations alongside those sources. A citation is the link an AI answer shows as its evidence, and it is one of the few ways an answer sends a reader to a website. If the answer has no citation, no website gets the visit, however much of its advice the answer repeats.

Gemini cites no source in 82.2% of home improvement answers, against 2.2% for ChatGPT. When answers do cite, energy.gov leads at 11.8%, and government and university websites take 39.2% of citations, nearly as much as every company, retailer and manufacturer combined.

On September 23, 2026 we asked ChatGPT and Gemini 400 home improvement questions, each twice, as part of a wider study of AI sources across 12 industries. That gave 1,600 answers, 924 of which cited at least one source, and 874 different websites were cited across them.

A website's share is the percentage of sourced answers that cite it at least once, counting all pages from the same site together. We also sorted every citation by the kind of website behind it: government and education (.gov, .edu and .mil addresses), nonprofits and associations (.org), media and reference publishers, user-generated sites such as forums, social media and video platforms, and companies and other commercial websites. The same measures were taken for the other 11 industries.

Gemini cites a source in 17.8% of home improvement answers. Only recipe questions, at 82.6%, go unsourced on Gemini more often. ChatGPT cites a source in 97.8% of home improvement answers and lists 2.8 websites on average, more than in most industries. Across both engines, 42.2% of home improvement answers cite nothing, almost all of them from Gemini.

The few Gemini answers that do cite lean on crowd and reference sites: Reddit leads at 14.1% of its sourced answers and Wikipedia follows at 11.3%. ChatGPT's leader is energy.gov at 13.6%, and the university sites that fill its list barely appear on Gemini. A home improvement business has two very different engines to plan for: one that credits experts and one that mostly credits no one.

After the Department of Energy come openstax.org (8.4%), the free textbook library run by Rice University, and the EPA (6.6%). Then comes a run of state universities: Iowa State (6.5%), NC State (6.3%), Minnesota (5.2%), Maryland (4.4%), Florida (3.9%), Penn State (3.7%) and Clemson (3.1%). Most are land-grant schools whose extension services publish practical guides on lawns, gardens, pests, insulation and home energy, and extension.org itself ranks 14th at 3.6%.

Government and university websites take 39.2% of home improvement citations, almost level with the 40.3% for companies and other commercial websites, and second only to fitness among the 12 industries. The one manufacturer in the top 25 is the HVAC maker Carrier, at 1.9%. No website reaches one sourced answer in eight, so the list is spread across hundreds of sites and open to a specialist that answers a question well.

Home improvement ranks 2nd of 12 industries for government and university citations. User-generated content, meaning forums, social media and video, takes 1.6% of home improvement citations.

The pattern is unusual for a consumer category. In travel and software, companies take three quarters of citations; in home improvement, a question about a furnace, a lawn or a leaky basement is answered first from government research and university guides, and the businesses that do the work come second.

Your pages are cited alongside university guides and the Department of Energy, not just the contractor down the road, so build pages that complement them. The extension guides explain the principle; your pages can add the cost of the job in your area, the local code or permit rules, the products you install and why, and photos of real projects. Cite the energy.gov or university guide you agree with, then add the detail only a working contractor knows.

Plan for Gemini separately. It names no source in more than eight of ten home improvement answers, so what counts there is being named in the answer: a consistent business name, service area and specialty across your website, Google Business Profile and directories. Our seo for contractors programs build the cost, code and project pages that AI answers can cite.

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