Summary

To use the loft as a habitable ‘warm space’, insulation can be installed in between and either above or below the rafters.

Cost/difficulty

MEDIUM COST

MEDIUM DIFFICULTY – Although this is a relatively simple measure, it is recommended to appoint a competent tradesperson to carry out these works.

Applicability in Letchworth

Applicable – No specific requirements.

Other things to consider

“Consider using a natural, breathable insulation such as wood fibre as these types of materials provide better moisture control, reducing the likelihood of condensation issues.

In addition, higher density insulations such as wood fibre absorb sound very effectively and provide good ‘thermal mass’ benefits, helping to minimise overheating in the summer months and keep the building warm in the winter.”

Case study

Links to further information

• Energy Efficiency Guide for Letchworth Garden City residents (2024), page 5
• The Surrey Home Energy Improvement Guide (2025), page 52

Image credits – Steico

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This guidance is part of Roofs, Ceilings and Loft Spaces

See more guidance notes on this topic below:

• Insulation between joists
• Photovolatics {link}