The site is built with plain HTML and CSS. Pages use a clear heading order, text alternatives for images, readable color contrast, form fields with labels, and layouts that work on phones, tablets and desktops. The cost calculator, quiz and area check run in the browser and can be used with a keyboard. Questions and answers are shown as open text rather than hidden panels.

The goal is to meet the Web Content Accessibility Guidelines 2.1 at level AA. Some parts may still fall short, and the site is checked and improved over time.

If any page, tool or form is hard to use, send a note through the contact form describing the page and the problem, plus the browser or assistive tool you use if you know it. If you can't use the form, say so in any message you are able to send, and another way to share your request will be worked out.