Engineering English
R-value
Energy Engineering · Last updated: July 30, 2026 · How this entry was written
Definition: The R-value is a measure of thermal resistance used in building construction to indicate how well a material resists heat flow. Higher R-values provide better insulation and reduce heat loss through walls, roofs, and floors.
Example in context
“Installing attic insulation with an R-value of 38 will significantly reduce heat loss and lower the building's heating demand.”
“R-değeri 38 olan çatı katı yalıtımı monte etmek, ısı kaybını önemli ölçüde azaltacak ve binanın ısıtma talebini düşürecektir.”
Where engineers use it
R-values are used in building energy codes, insulation product specifications, and energy audit reports. Engineers check R-values to design efficient building envelopes and to evaluate retrofit upgrades that reduce heating and cooling loads.
Synonyms: thermal resistance value, R-value insulation
Antonyms: U-value
Practice: can you use “R-value” at work?
You are auditing an older home. The owner says the walls feel cold in winter. You measure the insulation depth and find only R-11. Recommend a target R-value for the climate zone and explain the energy savings potential.
Show a model answer
“Check the R-value of the existing attic insulation to determine if additional layers are needed for energy efficiency.”
“R-value” in 21 languages
| English | R-value |
|---|---|
| Turkish | R-değeri |
| French | valeur R |
| German | R-Wert |
| Spanish | valor R |
| Chinese | R值 |
| Arabic | قيمة R |
| Portuguese | valor R |
| Russian | R-значение |
| Japanese | R値 |
| Italian | valore R |
| Vietnamese | giá trị R |
| Hindi | R-मान |
| Thai | ค่า R |
| Indonesian | nilai R |
| Korean | R값 |
| Bengali | R-মান |
| Dutch | R-waarde |
| Swedish | R-värde |
| Finnish | R-arvo |
| Ukrainian | R-значення |
Frequently asked questions
What does R-value mean in engineering?
The R-value is a measure of thermal resistance used in building construction to indicate how well a material resists heat flow. Higher R-values provide better insulation and reduce heat loss through walls, roofs, and floors. In Energy Engineering, the term carries a usage-frequency rating of 10/10 in the Engineering English library.
How do you pronounce R-value?
R-value is pronounced /ɑːr ˈvæljuː/ (IPA). The Engineering English app plays audio for the term and checks your pronunciation with speech recognition.
How is R-value used in a sentence?
Example from an engineering context: “Installing attic insulation with an R-value of 38 will significantly reduce heat loss and lower the building's heating demand.”
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