Most WikiHouse files and information are licensed under a Creative Commons–Sharealike licence, so you are free to use, distribute or modify them, including commercially.
All WikiHouse information is shared 'as is', without warranties or guarantees of any kind. You are responsible for checking it and using it in a safe and responsible way, for example, getting it checked by a structural engineer.
You are responsible for making sure your project complies with all relevant local regulations, including planning, building codes and health & safety legislation. If in doubt, seek professional advice.
If you make any improvements to the system, you must publish your files under the same type of open licence. However, you do not need to publish the plans and specifications for individual projects unless you wish to.
Do not call your company, organisation or any marketed product or service 'WikiHouse'. However, you may use the term WikiHouse to talk about the system, and you may describe your project, product, service or organisation as, for example, "using WikiHouse", "based on WikiHouse", "contributing to WikiHouse", or similar.
Do not remove any licence notices from files if you are re-sharing them.
Do not give the impression that you are endorsed by, or affiliated with WikiHouse or Open Systems Lab (unless you are, by written agreement), and do not claim to represent the WikiHouse project or community as a whole.