# U-Value Meaning in Green Building

> The U-value measures how much heat passes through a wall, roof or window. See a hotel glazing example and how SuperWise holds the specification.

Canonical: https://superwise.site/glossary/u-value-thermal/
Last updated: 2026-11-01

A measure of how much heat passes through a wall, roof or window, where a lower figure means better insulation.

## What is U-Value (Thermal Transmittance)?

A U-value is the rate of heat transfer through a structure, such as a wall or a glass window, divided by the temperature difference across it. It is also called thermal transmittance and is measured in W/m²K. A lower U-value means better insulation. In the hot Indian climate, a low U-value cuts the electricity that air conditioning uses.

## Practical example

An architect designing a luxury hotel in Dubai or Delhi rejects standard single-pane glass, which has a U-value of 5.8 and lets a large amount of heat in. The architect specifies a double glazed unit (DGU) with a Low-E coating instead, which brings the U-value down to 1.8, keeps the interior cooler and cuts the [HVAC](https://superwise.site/glossary/hvac/) electricity bill.

## In SuperWise

In SuperWise a U-value requirement can be written in the specifications of an RFQ line and again on the purchase order line, where it prints on the PO. A resource such as facade glass can also carry a quality checklist that the site team fills at delivery, with number and photo fields for the rated value on the manufacturer's data sheet.

[Quality and safety checklists](https://superwise.site/features/construction-quality-safety/)

## Related terms

- [HVAC (Heating, Ventilation, and Air Conditioning)](https://superwise.site/glossary/hvac/)
- [XPS Insulation (Extruded Polystyrene)](https://superwise.site/glossary/xps-insulation/)

## Related
- [HVAC (Heating, Ventilation, and Air Conditioning)](https://superwise.site/glossary/hvac/)
- [XPS Insulation (Extruded Polystyrene)](https://superwise.site/glossary/xps-insulation/)
- [Quality and safety checklists](https://superwise.site/features/construction-quality-safety/)