Terms of Use

Effective 5 August 2026

These are the terms for using Tiang, the home design and simulation app made by Tiang (“Tiang”, “we”, “us”). By installing or using the app you accept them. If you do not, please do not use the app. Like the privacy policy, this is written to be read.

What Tiang is — and what it is not

Tiang is a design and estimation tool, not professional advice. The temperature, humidity, electricity, solar and WiFi results it produces are estimates, produced by simplified physical models from the building you drew and the weather data available for the place you pinned. They are there to help you compare choices — this wall against that one, this much insulation against more — and to show you which direction a decision moves things.

They are not a substitute for an architect, an engineer, an electrician or a building surveyor, and they are not a compliance calculation. Do not use them as the basis for structural, electrical, thermal or safety decisions, for building control or permit submissions, or for anything where being wrong has a cost. Real buildings differ from drawings, weather differs from forecasts, and materials differ from their datasheets. Have anything that matters checked by a qualified professional for your jurisdiction.

We do not warrant that the results are accurate, complete or suitable for any particular purpose, and we are not liable for decisions taken on the strength of them.

Your account

You can draw without an account. Signing in with Google turns on backup, sharing and subscriptions. You are responsible for the Google account you sign in with; do not share it with people you would not want reading your projects.

You must be at least 13 years old to use Tiang.

Your designs are yours

You own what you draw. We claim no rights over your projects. We store and transmit them only to run the service you asked for — backing them up, syncing them to your other devices, running the simulations, and sharing them with people you invite. We do not use them to train anything, we do not show them to anyone you did not invite, and we do not sell them. See the privacy policy for the detail.

The free tier and Tiang Pro

Drawing is free and unlimited. Simulations, timelapses and PDF export have a monthly allowance on the free tier; the current numbers are shown in the app. We may change those allowances — they exist to keep the server affordable, and what one run costs us is not fixed forever.

Tiang Pro is a subscription sold through Google Play. Payment, renewal, price changes and refunds are handled by Google under their terms, not by us: manage or cancel it in Google Play → Subscriptions. A subscription renews until you cancel. Deleting your Tiang account does not cancel it — cancel in Play first, or you will keep being charged.

If a subscription lapses, your projects stay where they are. You keep everything you drew; the paid features stop.

Using it fairly

Please do not: work around the free-tier allowance, whether by rotating accounts or otherwise; attack, overload or probe the service; reverse-engineer the app except where the law says you may; resell access to it; or use it to break the law. We may suspend an account that does these things.

The service can change

Tiang is developed by one person and it changes often. Features may be added, altered or removed, and the app requires a working version to reach the server — very old builds stop being supported. We will not remove your ability to open and export designs you have already made without warning.

We do not promise the service will be uninterrupted. It runs on a single server and it will occasionally be down.

Ending it

You can stop at any time: delete your account inside the app under Profile → Delete my account, which removes everything synced to it, or simply uninstall. We may suspend or close an account that breaks these terms, or if we have to stop running the service — in which case we will give what notice we reasonably can.

Liability

Tiang is provided “as is”. To the extent the law allows, we exclude implied warranties, and we are not liable for indirect or consequential loss, lost profits, lost data, or the cost of building work. Where liability cannot be excluded, it is limited to what you have paid us in the twelve months before the claim — which, if you have never subscribed, is nothing.

Nothing here limits liability that cannot be limited by law, including for death or personal injury caused by negligence, or for fraud. If you are a consumer, you keep every right your local law gives you, and nothing in these terms takes those away.

Other people’s services

Tiang uses Google sign-in, Google Play, RevenueCat, and the weather and map services listed in the privacy policy. Their terms apply to their parts, and we are not responsible for them being available or correct.

Law

These terms are governed by the laws of the Republic of Indonesia, where Tiang is made. If you are a consumer somewhere else, this does not deprive you of the protection of the mandatory consumer law where you live.

Changes

We may update these terms. When something material changes, the effective date at the top changes with it. Continuing to use the app after that means you accept the new version.

Contact

Questions about these terms: tiangbuildingapp@gmail.com.