Your uninsulated loft is responsible for 25% of the heat escaping through the attic. Loft insulation can save energy depending upon the type of insulation you use for insulating your loft space. Whether you use blanket insulation, spray foam insulation or insulation board it depends on whether you need a cold loft or a warm loft.
As the suitability of insulation depends on your requirements, choosing the right type of loft insulation becomes more complicated. In this guide, we will help you identify your property needs and choose the suitable type of insulation and insulation material.
What Is the Best Type of Loft Insulation for Your Home?
According to a research briefing published in the House of Commons Library, 33% of UK homes (8.5 million) have less than 125mm of loft insulation.
This is far lower than the standard minimum limit of 270mm attic insulation. Choosing the right type of insulation type and material will determine how energy-efficient your house is.
Here are a few Types of thermal insulation for your loft:
Blanket Insulation
The blanket is one of the most commonly used loft insulation materials. This insulation roll is made of rock, glass, or mineral fibre which are the most effective and environment friendly.
Banket insulation is the most cost-effective insulation and serves as all-purpose insulation, especially for joists. It is usually suitable for underneath the loft floor and can be a messy choice for the underside of the roof.
Loose-Fill Insulation
Materials like cellulose fibre, mineral wool, cork granules, and recycled newspaper make this lightweight insulation material. It’s usually not considered really secure so it’s commonly used to top-up the existing insulation. Loose fill can also be used as its own but that can be messy.
Sheet Insulation
Made of synthetic or natural materials, sheet insulation includes firm boards. this firm board makes the best insulation material for the underside of the loft roof.
These boards insulate your attic space effectively and can be decorated over. This insulation type can be on the expensive side though, so if you have budget constraints, pick accordingly.
Blown-In Insulation
Loose materials like fibre are blown in joists and other hard-to-reach places. Blown-fibre insulation is perfect for draughty roofs but might not serve as a complete solution. It can be on the expensive side and needs professional installation, and can’t be installed by DIY methods.
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How to Decide Whether You Need Cold Loft or Warm Loft?
First, you need to understand their differences. Both the cold and warm lofts are the process of insulating your loft but for different purposes. Cold lofts are installed when you use your loft for storage. whereas, a warm loft is insulated when you are using the loft space as a living area.
In cold lofts, only the underneath of the loft floor is insulated to improve the household temperature. While in warm lofts, the underside of the roof, rafters, studs, and all the areas are insulated with draught proofing to prevent heat from escaping through the loft.
If you are using your space for storage, you should go for a cold loft or go for a warm loft otherwise.
What are Suitable Materials for Loft Insulation?
Let’s explore why choosing the right loft insulation material is absolutely crucial for your home! When it comes to making your living space cosy, using the best loft insulation isn’t just about ticking boxes – it’s scientifically proven to boost energy efficiency, slash heat loss, and keep your home wonderfully warm during those chilly months!
Fiberglass Insulation
Let’s talk about the superstar of loft insulation materials! Fibreglass insulation has earned its spot as one of the most popular choices for loft insulation and for good reason!
Available in both batts and loft insulation rolls, this type of loft insulation is perfect for fitting between the joists of your loft floor.
Benefits of Fiberglass Insulation:
- That impressive R-value! We’re talking top-notch heat flow resistance that’ll make your heating costs bow down in respect.
- Comes with built-in flame-retardant properties – safety first, folks!
- Amazing soundproofing abilities – those acoustical properties make it a champion at sound insulation.
- Non-combustible nature makes it stand out from other insulating materials.
Pro installation tip: When installing insulation between your exterior walls and walls and floors, think of it like a perfect puzzle – no voids allowed! Those gaps are just sneaky heat thieves!
Mineral Wool Insulation
Say hello to the dynamic duo of the insulation world – glass wool and rock wool! This type of loft insulation is particularly fantastic for loft insulation between rafters, bringing some serious thermal insulation performance to the party.
Why Choose Mineral Wool Insulation?
- Handles condensation like a pro – perfect for roof insulation.
- Non-combustible and flame-retardant properties make it a good choice for safety.
- Durability that makes other insulation products jealous.
For cold loft insulation in the UK, this ceiling insulation option is hard to beat!
Cellulose Insulation
Here’s an insulation superstar for our eco-conscious friends! When it comes to blown-in insulation, cellulose insulation is like the superhero of sustainable building insulation. Made from bonded, recycled paper materials, it’s changing the game in loose-fill insulation!
Advantages of Cellulose Insulation:
- Sustainable home insulation that Mother Earth gives a thumbs up to!
- Those air-sealing properties? Simply outstanding for tackling those sneaky leaks.
- Top-notch fire resistance thanks to clever retardant treatments.
Installation tip: As blown fibre insulation, it’s like magic dust for your loft spaces – filling every nook and cranny, from the tiniest cavities to those tricky gaps!
Spray Foam Insulation
The spray foam insulation is available in both rigid foam and foam board versions. It can be installed in impossible-to-reach areas as compared to batt insulation and caulk.
Key Features of Spray Foam Insulation:
- Boasts an R-value that’ll make your energy bills do a happy dance.
- Says “goodbye” to moisture problems in crawl spaces and masonry areas.
- Acts as an air barrier that seals gaps like nobody’s business, minimizing energy use.
Foil Insulation
Last but definitely not least, let’s shine a light on foil insulation! This reflective insulation is the clever cousin in the family of loft insulation materials, using aluminium layers to create a radiant barrier that’s perfect for loft insulation boards.
Why Use Foil Insulation?
- Works as a radiant barrier that reflects heat like a mirror.
- Perfect for warm loft insulation when you want to keep that loft living space cosy.
- Installation’s a breeze – whether you’re attaching it to the inner roof of the loft or the joists of your loft floor.
How To Choose the Best Loft Insulation for Your Needs
When selecting the best type of loft insulation, consider the following factors:
- R-value (thermal resistance): The higher the R-value, the better the insulation is considered.
- Energy-efficiency: Some insulation types, such as rigid insulation, provide better efficiency than others.
- Cost: Blanket insulation and blown-in insulation are more budget-friendly than spray foam insulation.
- Moisture resistance: Some insulation materials help prevent condensation and humidity issues.
If you want to use your loft for storage, you may need loft legs to elevate the flooring above the insulation.
Final Thoughts
Choosing the best loft insulation is crucial for improving home insulation. It also reduces heat loss and lowers heating costs. Multiple insulation options are available, including blanket insulation, blown-in insulation, rigid insulation boards, and spray foam insulation.
Ensuring there are no voids, maintaining adequate ventilation, and using vapour-barrier materials where necessary can significantly enhance energy-efficiency. If you’re unsure, hiring professional loft insulation services can help you land the best insulation for your needs.
FAQs
Your old insulation might have lots of dust and dampness. So, it’s wise to remove the old insulation before installing the new one. Plus, who knows what your old loft has been carrying over the years. Additionally, your new insulation also needs room to expand at its best.
No, you should only put the recommended amount of insulation material in your loft. Otherwise, you might face inadequate temperature and lack of ventilation. So, you should keep the insulation within the required limit which is 270mm.
No, you should never push the insulation up to the eaves of your loft. It will mess with the airflow and ventilation. This will not only cause inadequate temperature but also might cause moisture damage to the material. Issues like damp formation are common to surfaces.
It depends on your choice of materials. Different materials have separate durability and lifespan. It also depends on how you maintain the loft, keep it safe from moisture and provide proper ventilation.
Over insulation can cause humidity and moisture in your loft space due to lack of ventilation and air flow. This might lead to dampness and mould formation in your loft. These damages can reduce the lifespan of your insulation, requiring you to replace it earlier.


