The short version: no cookies, no analytics scripts, no email capture, and no account needed. What you type stays in your browser unless you send it yourself; the AI checks process your upload once and discard it, the optional last step of the journey shares an anonymous cost figure if you press the button, and the optional account holds your login, your credit and whatever you chose to save with a save button. The complete picture, including the few things I do count.
The tools remember your work in your own browser storage, so a reload does not throw it away. Nothing in this list is sent anywhere by itself. There are two exceptions, both voluntary and both described below: at the end of the renovation journey you can pass on what your project cost, and if you are signed in you can save an estimate or an impression to your own account. Each of them happens only when you press the button yourself.
renovationstart:calculator: your last calculator choices (project, size, finish, region).verbouwstart:ruimteplanner: your room planner layouts and unit preferences (the name comes from the shared planner code with my Dutch sister site).verbouwstart:droomhuis:v1: your house design from Design your own house (floor plan, storeys, roof, garden, objects and your own parts), so a reload does not throw it away; "Start over" on the drawing board clears it. The name comes from the shared code with our Dutch sister site.verbouwstart:werkplaats:v1: the piece you design on Design your own furniture, so a reload does not throw it away. The print file and the technical drawing are made in your browser; nothing goes to a server for them. With "Put it in your house" the piece waits in verbouwstart:werkplaats:naar-huis (session only) until the drawing board picks it up; that slot is empty straight after.verbouwstart:droomhuis:overdracht (session only): a hand-over slot the drawing board uses to pass a design between its own pages; emptied as soon as it is read.verbouwstart:droomhuis:naar-verbouwplan (session only): when you press "Take this house to the renovation plan", the items and amounts of the house you drew wait here for the result page. It stays in this browser tab; nothing goes to a server.verbouwstart:tekentafel:instellingen and verbouwstart:tekentafel:versies: how you set the drawing board up (what drawing snaps to, whether it aligns and how close, which panels are open, and how often it takes a snapshot), plus those snapshots themselves. Each snapshot is a copy of your design at that moment, at most as many as you set, so you can go back to how it looked half an hour ago; one you pin stays until you remove it.Nothing here goes to a server. The settings screen shows how much room it takes and clears it with "Clear versions" and "Back to defaults".
verbouwstart:wereldbol:plek: the place you last chose on the globe (city, country and, in the Netherlands, the municipality), so your next visit opens there. It is a convenience, not a fact about you; before your first choice the globe simply opens in the country of the language you are reading.verbouwstart-bouwjouwhuis-bestanden holds the STL, OBJ or glTF files you load as your own parts, and verbouwstart-productfotos holds a photo you attach to an object or the photo of your existing house (key eigenhuis:foto).Both stay in your browser; the photo of your house is sent once for a description when you press the button, and not kept.
renovationstart:gebruik_… (session only): remembers that an anonymous counter already fired this session, so nothing is counted twice.verbouwstart:mijlpalen:…, verbouwstart:wizard-verstuurd and verbouwstart:hulp-aanbod-klaar (session only): which steps of the calculator or the drawing board were already counted this visit, whether you just sent the step-by-step calculator, and whether you already closed or used the offer of Help.verbouwstart:herkomst: after a tap on a link in Help, where that tap came from and which page it led to, for at most ten minutes; it is removed as soon as that page has counted it.verbouwstart:impressie:v1: your latest AI impression (your photo, the result and the last steps), kept for up to seven days so a reload does not throw away your work; the "Clear and start over" button under the impression removes it. The photo itself is still never stored on a server, whether or not you save the result to your account.renovationstart:extras:v1: your extras log (descriptions, amounts, agreed-in-writing ticks and your contract sum).renovationstart:budget-tracker:v1: your spending tracker (budget and payment lines).renovationstart:first-fix:v1: which first-fix checks you ticked.renovationstart:snagging-checklist: which snagging checks you ticked.renovationstart:koper-scan:v1: your house-viewing comparison (the labels you typed for each house, the jobs you ticked for it and any asking price you added), kept for up to ninety days; removing a house or clearing the comparison deletes it.renovationstart:werkomschrijving:en: the sizes and choices of the schedule of works you downloaded for an extension (no amounts, no name or address), so the page for comparing quotes can find it again. Nothing about it is sent to a server.renovationstart:werkomschrijving-tekening:en: when you download the schedule of works from the drawing board, which parts of your drawing (rooms, walls, windows and doors, by their reference in the drawing) each item comes from, next to the same sizes and choices. The comparison uses it for "Show in drawing". It stays on this device and is never in the link, the QR code or anything sent to a server.renovationstart:vergelijk-keuze:v1: the quote you picked under your comparison report, when you pick one: its letter, its total and whether that includes VAT, what it asked per item, its provisional sums and its open questions, so your budget tracker and extras log can use them. Not the quote files, not the other quotes. Picking another quote replaces it; clearing your site data removes it.renovationstart:vergelijk-aankoop:en: the reference of your purchase when you pay for a quote comparison, so you can compare again with the same purchase and ask for your money back. It is a random string, with no name or amount.With the purchase itself, the server keeps its status, how many times you compared, the times, and from the payment your email address and Stripe's payment reference, to refund you and to apply the guarantee once per email address. Your quotes and the report are not kept.
renovationstart:renovation-record: your renovation record (property address, who did each job, which documents you hold, your notes).renovationstart:journey:v1: your renovation journey (chosen project, budget, region, which steps you completed and what you filled in along the way).renovationstart:journey:corrupt-backup: a safety copy the journey keeps if its own data ever turns out unreadable, so nothing is silently lost.renovationstart:intro-seen: remembers that the opening animation has played, so it only plays once.renovationstart:hulp-plan: the steps you asked Help to set out, and which of them you opened, so they are still there when you come back to it. Your question is not kept with them. They are deleted automatically thirty days after you last used them, and the clear button under the steps removes them straight away.verbouwstart:eigen-bezoek: a flag the maker uses to exclude his own visits from the counters.To know whether the tools are used at all, I record events like "the calculator showed a result for a loft conversion today" or "the planning check ended on orange today": the tool, a project type or outcome colour, and the day. Never an amount, never a postcode, never anything you typed, no cookie and no identifier. If you tap the optional thumbs up or down under an AI impression, I count that the same way: the verdict, the style, the room and the day, nothing else. If you then pick one of the four reasons after a thumbs down, I count that reason the same way.
When your free images or checks for the month are used up, the offer to buy credit appears. I count that it appeared, whether you pressed the buy button, and whether paying stopped because you were not logged in: which offer it was, the country and the day, nothing else. The embeddable widget counts the same way, plus the partner name and the website it is embedded on; nothing about the visitor.
How far a visit gets in the calculator or on the drawing board is counted the same way too: which step was reached (for example your own result, or a first change of your own), how you started (for example with an example house), whether you came in through a route or through Help, a time band (such as "10 to 30 seconds") and the day. Each step counts at most once per visit, with no identifier, nothing you entered, no amount and no design. Whether the quiet offer of Help appeared and whether you tapped it is counted the same way.
A feature that does send something: your room photo goes to the image model over an encrypted connection, is processed in memory and is not stored by me. The image is made by OpenAI's image model, which I call through the service OpenRouter; if you then place your own product in the impression, or if that service is unavailable, Google's image model (Gemini) makes it instead. All three process outside the EU and do not use your photo for training. A moderation step rejects photos with people. The free images of the month are counted on a salted, truncated hash of your IP address that changes every month, and a daily limit on free use protects the service with a hash that changes every day; neither can be reversed. Paid credit lives on your account.
On the buying-a-house page you can type a postcode and house number to fetch the construction age band and floor area from the official EPC register. That input identifies a building, not a person; it passes through my server to the register for that one lookup, is not logged and is not stored. The result stays on your screen, and is only kept if you save the house to your comparison yourself, on your own device.
The first of the two exceptions is the last step of the renovation journey, and it only happens if you press the share button there. It sends the project type, the region you picked, the final figure you type in and the date, plus, if you gave them, my estimate for the same project, the type of house and the score out of five for how the project went.
It does not send your postcode, your name, your address, your email or the name of whoever did the work; I do not ask who did the work. The entry carries no account, no cookie and no identifier, so it cannot be traced back to you.
Your browser can write one entry and can never read the collection back; the entries are mine to read, and none of them points to a person. Skipping the step changes nothing else about the journey, and the step itself lists what travels before you press anything.
Signing in is optional and changes nothing about how the tools work. It adds one thing: a save button under a calculator result and under a finished AI impression. Press it and that single item goes to your own account, and only then.
The site is served by Google Firebase Hosting. Like any host, the infrastructure keeps short-lived technical logs (such as IP addresses) to run and secure the service; I do not use them to identify visitors.
Questions? Email info@verbouwstart.nl (English is fine). This page describes the site as it works today, last updated 20 October 2026; if the way something works changes, this page changes with it. How the cost figures are built is a separate story: how we price.
No. The site sets no cookies at all, which is also why there is no cookie banner. Everything the tools remember lives in your own browser storage, listed on this page, and clearing your browser data removes it completely. If you sign in to the optional account, Firebase keeps your session in browser storage too, not in a cookie.
No. The calculator, the quote check on amounts you type, the planning check, the budget planner and the room planners run entirely in your browser. Amounts, postcodes, layouts and answers are never sent to a server on their own. Two things are voluntary exceptions, and both need a button press from you.
The last step of the renovation journey lets you pass on what your project actually cost; it goes without your postcode, your name and your email. And if you are signed in, the save button under a calculator result or an AI impression keeps that one item in your own account. The sections on this page say exactly what each of them contains.
It travels encrypted, is read once by the AI model to produce your report, and is discarded. It is not stored, not linked to you and never used for training. If you compare two or three quotes against your schedule of works, the text of each quote goes the same way, together with the items of that schedule, to find the price per item; nothing of it is stored, and the comparison stays only in the tab where you opened it.
If you first have quote A read for free, only that one quote goes the same way and the first point comes back; nothing of that is stored either. Between that reading and paying, your files stay only in the storage of your own browser, so you do not have to choose them again after paying; after the report, and in any case after a day, they are gone from there.
The comparison stays in your tab unless you pick one of the quotes: then the part of the report about that quote stays on this device (renovationstart:vergelijk-keuze:v1 in the list of what is stored on your device). To give one free check per month fairly, I keep a salted monthly hash of your IP address with a counter; it cannot be traced back to you and resets every month.
The company number you picked goes to my server in Europe, which reads the public Companies House register for that company and its directors. The findings from the register, and nothing about you, then go encrypted to Anthropic's language model, which writes the questions to ask. Nothing is stored: not the company, not the report. To give one free full check per month fairly, the same salted monthly hash of your IP address with a counter is used as for the quote check.
Your question and a short summary of your design (how many storeys, rooms and openings there are and which tool you are holding; no measurements and no address) travel encrypted to my server in Europe and from there to Anthropic's language model, which writes the answer. If you ask through the question mark at the top of a page, your question goes with the web address, title and heading of that page, and nothing you entered on the page.
If you had steps set out earlier or used one of the tools, at most a few words about that go along from a fixed list (calculate, permission, draw, quote, builder, renovation journey): which you already did and which step is still open, so Help does not send you back to what you have just done. No measurement, no amount, no address and nothing you entered goes with it, and anything not on that list does not get through. None of it is stored. I only count, with nothing that leads back to you, how many questions come in per day, on which topic, and whether an answer was found. To limit use per visitor I keep a salted, truncated hash of your IP address that changes every day.
If you ask Help to set out the steps for you, the same travels as with an ordinary question. Help then picks from a fixed list of tools on this site and does nothing in your account. Your browser remembers the steps (localStorage), so they are still there when you come back from a step and when you pick it up later; it does not keep your question with them. They are deleted automatically thirty days after you last used them, and the clear button under the steps removes them straight away. I only count how often steps were asked for and which kind of step was opened.
Your email address and password (the password encrypted by Firebase Authentication), your Renovation Pack credit (three counters, AI images, quote checks and full builder checks, plus the payment session ids that booked them) and anything you saved yourself with a save button: the estimates and the impressions listed on your account page.
Payment itself runs through Stripe; I never see your card details. The email address is used for signing in and password recovery, nothing else. You can delete each saved item, and the account itself, on the account page; that removes it permanently.
Your photo travels over an encrypted connection to the image model, is processed in memory and is not stored by me. The result comes back to your browser. If you are signed in and press save under the result, that result image is stored in your own account until you delete it; your original photo is never stored, saved or not.
To count your free images of the month, and to keep a daily limit on free use, I keep salted, truncated hashes of your IP address, one that changes every month and one that changes every day; they cannot be traced back to you and lose their meaning when the period ends.