What ChatGPT and Perplexity recommend for waterproofing in Singapore (25 Oct 2026)
In short (25 Oct, 1 run per prompt: 5 questions, each asked once on ChatGPT and once on Perplexity, 10 answers):
- ChatGPT named 3 to 5 firms in each answer (19 mentions, 12 different firms). Perplexity named 1 to 3 (9 mentions, 7 different firms).
- The two tools mostly named different firms. Across the 10 answers, 18 different firms were named, and only 1 of them was named by both tools. That firm appeared in 5 of the 10 answers.
- Our run log records a sponsored ad in 4 of ChatGPT's 5 answers; Perplexity showed none. Ads aren't counted as firms named.
Source: weCDEF check of ChatGPT (signed out) and Perplexity (free account, signed in), 25 Oct 2026, 09:54–10:05 SGT, from a Singapore connection. 25 Oct, 1 run per prompt. Prompts in the exact wording of our prompt set.
This study checked ChatGPT and Perplexity, asking each question once from a Singapore connection. Our client audits check ChatGPT and Google AI Overviews instead, asking each question 3 times from a Singapore connection (how we run each check). Perplexity isn't part of client audits, and Google AI Overviews weren't part of this study.
One answer per question per tool is a snapshot. AI answers change from one run to the next, so read these figures as a description of these 10 answers, not as a ranking.
What we asked
The 5 questions
These come from our fixed waterproofing prompt set. They're written the way homeowners type: lowercase, casual, no firm names. Each was pasted exactly as written.
| ID | Type of question | Prompt |
|---|---|---|
| WP-01 | best | best waterproofing contractor in singapore |
| WP-02 | best | which company is good for toilet waterproofing in singapore? need someone reliable |
| WP-03 | near-area | waterproofing contractor near tampines, singapore |
| WP-04 | near-area | roof leak repair for landed house near bukit timah, singapore |
| WP-13 | best | recommend a waterproofing specialist for condo balcony leak singapore |
Source: weCDEF prompt set v1.1; wording as run on 25 Oct 2026.
How we ran them
Each question was asked once on ChatGPT, signed out, and once on Perplexity, on a free account, from a Singapore connection. We saved a screenshot of every answer, logged the time in Singapore time, and counted only firms named in the answer itself, not in sponsored ads. There's more on how we work in how we run each check.
What the tools returned
How many firms each answer named
| WP-01 | WP-02 | WP-03 | WP-04 | WP-13 | Mentions | Different firms | |
|---|---|---|---|---|---|---|---|
| ChatGPT | 5 | 3 | 4 | 4 | 3 | 19 | 12 |
| Perplexity | 3 | 1 | 1 | 2 | 2 | 9 | 7 |
Source: weCDEF check, 25 Oct, 1 run per prompt, Singapore connection. A "mention" is a firm listed in the answer text (one item per page showed no name and is identified by its link); sponsored ads are excluded.
How much the answers overlapped
- 18 different firms were named across the 10 answers. 11 were named once.
- 1 firm (call it firm 1) was named by both tools: in 3 of the 5 Perplexity answers and 2 of the 5 ChatGPT answers.
- 7 firms were named in 2 or more answers. Apart from firm 1, each of those was named by one tool only.
Source: as above. With 28 mentions, we don't give percentages.
Which sources they cited
| ChatGPT (5 answers) | Perplexity (5 answers) | |
|---|---|---|
| Terris (listing and editorial site) | 0 answers | 3 answers |
| BCA's website (government) | 0 answers | 2 answers |
| "Best of" list sites | 0 answers | 2 answers |
| MoreBetter (editorial site) | 1 answer | 1 answer |
| Bumble Scoop (lifestyle site) | 2 answers | 0 answers |
| Google (Maps and business listings) | 1 answer | 0 answers |
| Other sites, each referenced in one answer (a directory, a classifieds site, a job-matching platform, a blog, a property-price site) | 1 site | 4 sites |
Perplexity lists about 10 sources with every answer; ChatGPT shows a few source chips. The table counts the answers in which each source appeared, as far as our screenshots show. Counts aren't clicks. Sponsored ads aren't counted as sources.
Source: weCDEF check, 25 Oct, 1 run per prompt, Singapore connection.
Screenshots
What this does and doesn't show
This is a small sample: 2 tools, 1 run per prompt, 5 prompts, on the morning of 25 Oct 2026, from a Singapore connection. AI answers change between runs, so a firm named once here might not be named next time, and the reverse. Signed-in ChatGPT users, other Perplexity accounts, other places and other days may see different answers. Google AI Overviews weren't checked. An IP lookup service classed the connection as a privacy or VPN address; we don't know whether either tool treated it differently. This shows what was returned that morning, not how either tool ranks firms, and not what any firm should expect.
What a waterproofing firm can check for itself
The two tools drew on different sources: Perplexity referenced listing and "best of" sites more often. That's what they cited on one morning, not how they choose. Still, these are reasonable things to check:
- Your own website. Does it state your price ranges and answer common homeowner questions (how long the job takes, whether tiles need hacking, what the warranty covers) in plain text, not only in images?
- Your listings. Where you're listed on directories or "best of" pages, are your name, phone number and services correct and the same as on your website?
- Your Google business listing. Is the category right, and do your details match your website exactly?
- Your reviews. Are they genuine, recent and replied to? Never buy, swap or write reviews, and don't offer anything in exchange for them.
None of these will guarantee that an AI tool names you. If you'd like us to check them for your firm and record what AI tools say today, see how we run each check or request a free audit below.
FAQ
Do ChatGPT and Perplexity recommend specific waterproofing contractors in Singapore? In our sample, yes. Every one of the 10 answers named at least 1 firm: ChatGPT 3 to 5 per answer, Perplexity 1 to 3.
Do they recommend the same firms? Mostly not. Of the 18 firms named, only 1 was named by both tools.
Where do they get these recommendations? In our sample, Perplexity referenced a listing site in 3 of its 5 answers and BCA's website in 2. That's what they cited, not proof of how they decide.
Are the sponsored results counted? No. Our run log records a sponsored ad in 4 of ChatGPT's 5 answers. We left ads out of every count.
Why don't you name the firms? This is a study of patterns, not a ranking or an endorsement.
How can I check what AI tools say about my firm? Request a free audit. We run your trade's questions on ChatGPT and Google AI Overviews and send you dated screenshots, how often you were named, who was named instead, and a fix list.
Data and method notes
- Source: weCDEF check of ChatGPT (signed out) and Perplexity (free account, signed in), 25 Oct 2026. Waterproofing answers recorded 09:54–09:57 SGT (Perplexity) and 10:03–10:05 SGT (ChatGPT), from a Singapore connection. Some times are approximate.
- Runs: 1 run per prompt per tool, 10 answers in total.
- Prompt wording: exactly as written in our prompt set.
- How we counted: a mention is a firm listed in the answer text. Sponsored ads are excluded. Different spellings of the same firm's name are counted as one firm; two firms with similar names are counted separately. One ChatGPT list item showed no firm name but linked to a firm's website; we counted it as that firm. Source references include source chips shown without a web address.
- No firms named: we publish counts and source types only. Platforms and public sources are named; contractors aren't.
- Earlier check: a first pass on 18 Oct used a different connection and setup, so it isn't combined with these figures.
- Data file: not published yet. If we publish it, it will contain counts only.
Related: what ChatGPT and Perplexity recommend for renovation and interior design in Singapore · how we run each check · how we're testing our audit on our own sites first · weCDEF home