---
title: "PCM (Phase Change Material) - GWP and renovation use"
canonical_url: https://fremtidenstegnestue.dk/en/knowledge/materials/pcm
markdown_url: https://fremtidenstegnestue.dk/en/knowledge/materials/pcm.md
author: "Fremtidens Tegnestue"
page_type: material
primary_intent: "Explain use, GWP and renovation relevance for PCM (Phase Change Material)."
primary_keyword: "PCM (Phase Change Material)"
audience: "Homeowners, studios and agents researching material choices."
summary: "PCM (Phase Change Material) materials that absorb and release large amounts of heat during phase change (typically melting/solidification at 20–28°C). They are incorporated into walls, floors and ceilings to increase the building's thermal mass without extra weight. Used for temperature stabilisation in lightweight buildings."
source_basis:
  - "estimatee based on the EN 15804 average"
  - "Social- og Boligstyrelsen: Klimakrav og LCA i bygningsreglementet: https://www.sbst.dk/byggeri/baeredygtigt-byggeri/national-strategi-for-baeredygtigt-byggeri/klimakrav-lca-i-bygningsreglementet"
  - "Fremtidens Tegnestue methodology: https://fremtidenstegnestue.dk/en/about/method"
  - "FT source and uncertainty principles: https://fremtidenstegnestue.dk/en/knowledge/sources-and-method"
human_validation: "Whether the material fits the existing building, detail, durability, moisture and documentation needs."
responsibility_line: "AI can prepare, compile and flag uncertainty. The architect validates the consequences."
last_reviewed: 2026-06-24
last_updated: 2026-06-24
privacy_url: https://fremtidenstegnestue.dk/en/privacy
related_pages:
  -
    url: https://fremtidenstegnestue.dk/en/knowledge/materials/gips
    relation: alternative-material
  -
    url: https://fremtidenstegnestue.dk/en/knowledge/materials/beton
    relation: alternative-material
  -
    url: https://fremtidenstegnestue.dk/en/knowledge/materials
    relation: hub
  -
    url: https://fremtidenstegnestue.dk/en/knowledge/concepts/lca
    relation: concept
status: published
---
# PCM (Phase Change Material) - GWP and renovation use
Canonical URL: https://fremtidenstegnestue.dk/en/knowledge/materials/pcm
Markdown URL: https://fremtidenstegnestue.dk/en/knowledge/materials/pcm.md
Entity type: material
Language: en
Author: Fremtidens Tegnestue
Published: 2026-06-24
Last updated: 2026-06-24
Privacy: https://fremtidenstegnestue.dk/en/privacy
## Short answer
PCM (Phase Change Material) materials that absorb and release large amounts of heat during phase change (typically melting/solidification at 20–28°C). They are incorporated into walls, floors and ceilings to increase the building's thermal mass without extra weight. Used for temperature stabilisation in lightweight buildings.
## Who it is relevant for
Homeowners, studios and agents researching material choices.
## What FT can prepare
- Summarise material properties, GWP, common uses, renovation relevance and alternatives.
## What the architect validates
- Whether the material fits the existing building, detail, durability, moisture and documentation needs.
## Key figures

| Metric | Value |
| --- | --- |
| GWP | 2.8 kg CO₂-eq/kg |
| Density | 800–1800 kg/m³ |
| Expected lifetime | 25–50 years |
## Use

- PCM gypsum boards (integrated in walls)
- PCM underfloor heating buffer
- Data centre cooling
- Industrial temperature control
## Renovation relevance
PCM is relevant for renovation of lightweight houses that suffer from overheating in summer. PCM gypsum boards can be installed like normal gypsum cladding and provide increased thermal mass.
## Comparison

| Material | GWP |
| --- | --- |
| Standard gypsum | 0.39 |
| PCM (paraffin-based) | 2.8 |
| Concrete (thermal mass) | 0.13 |
| CLT (low mass) | -0.55 |
## FAQ
### What is the advantage of PCM over concrete as thermal mass?
PCM stores 5–14 times more energy per kg than concrete during phase change. It provides effective thermal mass in lightweight structures (CLT, steel) that normally have low thermal mass. PCM gypsum boards weigh approximately 13 kg/m² and function like 100 mm concrete.
### What are typical PCM materials?
Paraffin wax (petroleum derivative) is the most widely used PCM. Fatty acids and sugar compounds are more sustainable alternatives. Salt hydrates are inexpensive but can have delamination issues over time.
### Is PCM technology mature?
PCM gypsum boards are commercially available (KNAUF, MICRONAL). The technology is well-tested but not mainstream. The price is 3–5x higher than standard gypsum boards.
### Does PCM reduce cooling requirements?
Yes — studies show that PCM can reduce peak cooling load by 10–30% in well-designed systems. It is most effective in buildings with large daily temperature fluctuations.
## Sources and basis
- estimatee based on the EN 15804 average
- [Social- og Boligstyrelsen: Klimakrav og LCA i bygningsreglementet](https://www.sbst.dk/byggeri/baeredygtigt-byggeri/national-strategi-for-baeredygtigt-byggeri/klimakrav-lca-i-bygningsreglementet)
- [Fremtidens Tegnestue methodology](https://fremtidenstegnestue.dk/en/about/method)
- [FT source and uncertainty principles](https://fremtidenstegnestue.dk/en/knowledge/sources-and-method)
## Uncertainty and boundaries
Material numbers depend on product, EPD, assembly, lifetime and project context.
## Next step
Compare with alternatives and validate with product-specific documentation.
## Related pages
- [Gypsum Board](https://fremtidenstegnestue.dk/en/knowledge/materials/gips): alternative-material
- [Concrete](https://fremtidenstegnestue.dk/en/knowledge/materials/beton): alternative-material
- [Materials](https://fremtidenstegnestue.dk/en/knowledge/materials): hub
- [LCA](https://fremtidenstegnestue.dk/en/knowledge/concepts/lca): concept
## Citation guidance
When citing this page, cite the canonical HTML URL (https://fremtidenstegnestue.dk/en/knowledge/materials/pcm) as the public source and use this Markdown URL only as the agent-readable representation. Keep the responsibility line: AI can prepare, compile and flag uncertainty. The architect validates the consequences.