# Part J4 Info - [J4D3 Thermal construction — general](https://docs.betterbuilding.io/user-guide/workflows/energy-efficiency/part-j4-building-fabric/part-j4-info/j4d3-thermal-construction-general.md) - [J4D4 Roof and Ceiling Construction](https://docs.betterbuilding.io/user-guide/workflows/energy-efficiency/part-j4-building-fabric/part-j4-info/j4d4-roof-and-ceiling-construction.md) - [J4D5 Roof Lights](https://docs.betterbuilding.io/user-guide/workflows/energy-efficiency/part-j4-building-fabric/part-j4-info/j4d5-roof-lights.md) - [J4D6 Walls and glazing](https://docs.betterbuilding.io/user-guide/workflows/energy-efficiency/part-j4-building-fabric/part-j4-info/j4d6-walls-and-glazing.md) - [NCC 2019 Façade Calculator and Better Building](https://docs.betterbuilding.io/user-guide/workflows/energy-efficiency/part-j4-building-fabric/part-j4-info/j4d6-walls-and-glazing/ncc-2019-facade-calculator-and-better-building.md) - [Specification 37](https://docs.betterbuilding.io/user-guide/workflows/energy-efficiency/part-j4-building-fabric/part-j4-info/j4d6-walls-and-glazing/specification-37.md) - [J4D7 Floors](https://docs.betterbuilding.io/user-guide/workflows/energy-efficiency/part-j4-building-fabric/part-j4-info/j4d7-floors.md) --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.betterbuilding.io/user-guide/workflows/energy-efficiency/part-j4-building-fabric/part-j4-info.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.