Latent heat
When heat energy is added to a substance, its temperature generally rises, and when heat energy is removed, its temperature generally falls. This is referred to as ‘sensible heat’.
However, when a substance changes state, such as from a solid to a liquid, a liquid to a gas or vice versa, this change requires the addition or removal of heat energy, but does not result in a change in the temperature of the substance. This is referred to as latent heat.
There are three categories of latent heat:
- Latent heat of fusion: When a substance changes from solid to liquid (or back).
- Latent heat of vaporisation: When a substance changes from liquid to gas (or back).
- Latent heat of sublimation: When a substance changes solid to gas (or back).
Specific latent heat refers to the heat required to change the state of 1 kg of a substance without a change in temperature, expressed in joules per kilogram.
NB: This should not be confused with the term ‘specific heat’ which refers to the heat energy per unit mass required to raise the temperature of a substance by one degree Celsius.
[edit] Related articles on Designing Buildings
Featured articles and news
A call for prevention and sensitive re-use.
The CIAT principal designer register
Providing assurance and verification of the capability and competence of registered ATs.
Building Safety recommendations and Northern Ireland
The NI roadmap to improving safety in high rise residential.
BSA residential sector competence standards guidance
BSAS 01:2024 Organisational Capability Management System Standard - Competence Assurance.
Specifying rendered external wall insulation for fire safety
How to interrogate the evidence provided to the specifier.
The benefits of writing articles for your organisation
How to create a profile for your organisation and publish for free.
No Falls Week. The importance of safe working at height
What to expect and what is on offer to avoid accidents.
Scottish Government action to reach net-zero targets
Retrofit expert group highlight critical actions needed.
A forward thinking, inclusive global community of members.
From engineered product life-spans, to their extension.
Circular economy in the built environment
A brief description from 2021. Where are we now?
CLC publishes domestic retrofit competency framework
Roadmap of Skills for net zero.
Understanding is key to conservation.
Open industry engagement survey seeks responses
Institutions and the importance of engagement.