Why is Awaab’s Law such a significant moment for the housing sector?
The case of Awaab Ishak showed how poor housing conditions can lead to tragic consequences. The two-year-old’s death in 2020 from exposure to damp and mould prompted the introduction of Awaab’s Law under the Social Housing (Regulation) Act 2023, with the first measures taking effect in October 2025. From this point, social housing landlords will be legally required to investigate and fix dangerous damp and mould hazards within set timeframes, and tackle emergency hazards within 24 hours.[1] The law will be extended to include other household hazards, such as fire safety and excessive cold and heat, in 2026. The government is also consulting on how to apply Awaab’s Law to privately rented homes in the future.
What does Awaab’s Law mean for insulation?
Awaab’s Law has brought national and regulatory attention to the dangers of damp and mould in social housing, creating a clear obligation for landlords to provide healthier homes. At the same time, the sector is also under pressure to improve housing quality and energy efficiency. Good-quality insulation plays a crucial role, and the level of loft and wall insulation in homes in England has increased over the past decade.[2]
The challenge comes when materials are chosen purely for their ability to cut energy use, without considering how they interact with moisture, acoustics, and fire safety. In some cases, the drive for energy efficiency can unintentionally increase the risk of damp and mould. Legislation such as Awaab's Law underlines the need for thoughtful specification and planning of materials to support healthy buildings across all of these performance areas, with a particular focus on managing moisture.
Is damp an issue in England’s housing stock?
The age and condition of much of England’s housing stock make it especially vulnerable to damp. Many homes were built before 1919, and most of today’s social housing dates from between 1945 and 1980.[3] These older buildings are often poorly insulated and prone to moisture issues. The English Housing Survey,[4] commissioned by the Ministry of Housing, Communities and Local Government, found that problems with damp had increased since 2019, posing serious health risks to residents.
How does moisture become a problem?
Understanding how moisture builds up inside homes is essential to addressing the issue, and avoiding inadvertently making it worse.
Moisture levels vary between homes, depending on the age, construction, and location. A typical family of four can produce up to 10 litres of moisture per day through breathing, as well as daily activities such as cooking and washing.[5] Without adequate ventilation and heating, and suitable insulation, this moisture can become trapped, leading to persistent condensation – and ultimately, mould.
Regulating a building’s internal temperature can play an important role in managing indoor air quality and moisture levels. Temperature differences within different parts of a building affect airflow, which in turn influences how moist air moves and where it may condense. If insulation is applied unevenly or only to parts of the outside walls, ‘cold bridges’ can form – areas where warm, moist air condenses on cooler surfaces.[6]
Why does the type of insulation make such a difference?
Older buildings are often described as ‘moisture-open’, meaning they have been constructed from permeable materials like brick and stone, and typically have a lot of natural ventilation. Moisture-open materials allow moisture to move in and out of the building fabric, both as liquid and as vapour.
The most common types of insulation are typically either vapour-open or vapour-closed. Vapour-open materials can allow the movement of water vapour in moisture-open constructions. This helps to maintain the moisture balance within a building, reducing the risk of condensation. By contrast, vapour-closed materials block moisture movement, which is desirable in some applications but may lead to trapped damp in certain constructions.
Damp problems can emerge over time if older homes are retrofitted with insulation without taking their original construction into account – and the problem may be compounded if other vapour-closed materials have been installed that prevent airflow. Moisture can be trapped by retrofit systems if they are not properly designed and installed. This risk can be reduced by conducting a detailed survey before any remedial work begins, and by selecting the appropriate materials, determining whether moisture-open and vapour-open materials should be used.
What role can ROCKWOOL stone wool insulation play in moisture management?
Among the various insulation materials available, ROCKWOOL stone wool insulation – made from volcanic rock – stands out for its ability to be used effectively in constructions that are open or closed to vapour and moisture.
Our stone wool insulation is vapour permeable. Its ‘Mu-value’ – a measure of its water vapour resistance factor – is the same as that of air (µ = 1), making it vapour-open. This permeability means vapour can pass through without condensing and accumulating into moisture.
Our stone wool is also water repellent and non-hygroscopic, meaning it will not attract or absorb moisture from the surrounding environment [7].
As a result, ROCKWOOL stone wool insulation is a good candidate for retrofit applications in traditional, moisture- or vapour-open buildings.