Loft Insulation

ROCKWOOL loft insulation is made from stone wool, harnessing the benefits of naturally abundant stone to create insulation which is:

• Thermally efficient – tiny pockets of air trapped within the physical structure of stone wool help to regulate indoor temperature and prevent heat loss, keeping buildings warmer in the winter and cooler in the summer.
• Fire resilient – ROCKWOOL stone wool insulation is certified Euroclass A1 non-combustible. This means it is not flammable, and capable of withstanding temperatures in excess of 1,000°C.
• Sound reducing – stone wool insulation absorbs vibrations and traps unwanted sounds to reduce nuisance noise both to and from the home, and has been proven to reduce up to 40% of incoming noise near airports².
• Breathable – allows air vapour to pass through its structure and escape, reducing the risk of damp and mould which are common in lofts, and the remedial works they bring.
• Robust & adaptable – stone wool is dimensionally stable, yet able to be shaped, compressed and adapted to all kinds of loft designs, retaining its structure and performance without sagging.
• Durable – ROCKWOOL stone wool insulation has proven to last throughout a building’s lifetime without any reduction in its thermal properties³.
• Sustainable – ROCKWOOL stone wool insulation is made from an abundant natural resource and performs to the same high standard for decades. ROCKWOOL stone wool insulation is recyclable and can be transformed into new ROCKWOOL products. Over its lifetime, ROCKWOOL building insulation sold in 2023 will save 100 times the energy consumed in its production. Find out more about our sustainability credentials.

How to insulate a loft

Depending on loft usage and budget, there are many ways of insulating a loft space. Material options include spray foam, foils, foam boards, and mineral wool insulation which traps air within its structure to prevent heat transfer. The depth of insulation you need depends on your thermal performance target, and which material you choose.

A warm loft, designed as living space, needs insulation in the top rafters as well as the floor. A cool loft only insulates the lower joists or floor, and can be used for storage.

Cool lofts are the most common in the UK, as it is much easier, quicker, and therefore less costly to insulate only the joist, rather than between the rafters in the ceiling, and heating an unused space is impractical.

Many loft insulations can be carried out as a DIY project, but there is also the option to work with a recognised tradesman depending on the size, scale and complexity of works.

Loft or attic insulation can be installed by a local professional for optimal performance and peace of mind, but many installations can also be carried out as a DIY project.

If you are installing yourself, be sure to closely follow the guidelines for the products you’ve chosen – ROCKWOOL installation guidelines can be found through our website.

If you’re thinking about how to insulate a loft, here are some key considerations:

• Ensure you have accurate measurements of the area you are insulating
• Inspect all joists, structural elements and electrical cabling to ensure proper condition
• If rot, damp or moisture is present, consult a professional contractor to perform an investigation before progressing
• Evenly distribute insulation material and avoid open joints between products
• Avoid squashing loft insulation, as crushed air pockets within the insulation can affect thermal performance

_{[1] https://energysavingtrust.org.uk/home-insulation/roof-and-loft}

_{[2] https://www.rockwool.com/uk/advice-and-inspiration/why-stone-wool/acoustic-capabilities/}

_{[3] FIW, Durability Project Mineral Wool (2016), p. 29, Chapter 7 “Conclusions and Outlook.”}

_{[4] https://energysavingtrust.org.uk/advice/roof-and-loft-insulation/}