Evidence-Based Building Science • BS 5250 & PCA Guidelines

UK Damp & Mould Technical Guides

Unbiased, building-physics-backed guidance on identifying condensation, enforcing Awaab's Law, sizing dehumidifiers for solid-brick Victorian homes, and avoiding chemical damp-proofing misdiagnosis.

Showing 4 of 4 guides

Damp Diagnostics

8 min read

Condensation vs Rising Damp: How to Tell the Difference & Avoid Misdiagnosis

Learn how to accurately distinguish condensation from rising damp. Compare tide marks, black mould spores, dew points, and hygroscopic salt symptoms.

Key Takeaway:Over 75% of domestic damp complaints in UK pre-1930 homes are misdiagnosed as rising damp. If black mould is present, it is almost exclusively condensation: true rising damp contains nitrates and chlorides that inhibit mould spore germination.

Updated 4 Oct 2026Read Guide

Legal & Regulations

7 min read

Awaab's Law Explained: 2026 UK Landlord Damp & Mould Timelines & Legal Rights

Understand Awaab's Law and the Social Housing Regulation Act 2023. Mandatory 14-day investigation timescales, emergency hazards, and tenant legal rights.

Key Takeaway:Under Awaab's Law, UK landlords must investigate reported damp and mould hazards within 14 calendar days, provide written findings within 48 hours, and begin repairs within 7 days. Emergency hazards threatening respiratory health must be tackled within 24 hours.

Updated 4 Oct 2026Read Guide

Mitigation & Technology

6 min read

Best Dehumidifier Capacity for UK Victorian & Solid Wall Homes

Calculate the exact dehumidifier capacity needed for Victorian and solid-wall homes. Compressor vs desiccant, extraction litres per day, and running costs.

Key Takeaway:Do not buy a compact 500ml or 2L peltier dehumidifier for a Victorian house. Pre-1930 solid wall homes require an extraction capacity of at least 12L to 20L per day to maintain relative humidity between 50% and 55% during British winters.

Updated 4 Oct 2026Read Guide

Surveys & Property

7 min read

Pre-Purchase Damp Surveys: How to Avoid Mortgage Retentions & Chemical DPC Scams

Avoid costly mortgage retention clauses and £4,000 chemical injection scams. How independent PCA damp surveys protect homebuyers and mortgage approvals.

Key Takeaway:Never accept a 'free damp survey' from a remedial contractor with a financial incentive to sell chemical injections. Always commission an independent CSRT surveyor who does not sell building works to produce an unbiased mortgage-grade report.

Updated 4 Oct 2026Read Guide