Insulating your loft - what materials to use

Installing energy-efficient loft insulation could reduce your fuel bills by hundreds of pounds.

It’s also a DIY job you could tackle yourself. But what’s the best material to use to help keep your home cosy without breaking the bank?

Fibreglass and mineral wool insulation are both budget-friendly options with good thermal performance. What are the pros and cons?

Fibreglass

Fibreglass insulation is the kind of ‘glass wool’ blanket roll you’re probably most familiar with – we sell a lot of Knauf loft roll for example. It’s cost-effective, lightweight and easy to handle – but can irritate skin, eyes and lungs, so wearing protective gear is a must. It’s resistant to mould and provides an extra layer of fire protection to your home – but becomes less effective as it settles over time.

Mineral wool

Mineral wool insulation is made from natural or synthetic minerals, such as basalt, diabase or slag. Superior long-term thermal performance comes at a cost, but the extra density of a product like Rockwool, for example, can provide soundproofing too. As well as being fire-resistant, mineral wool is ‘hydrophobic’, meaning it’s resistant to moisture and prevents mould growth. Heavier than fibreglass, it can be awkward to handle – so installation is often a job for a professional.