News A Comprehensive Guide to Calculating Loft Insulation Requirements


A Comprehensive Guide to Calculating Loft Insulation Requirements

Insulating your loft space is one of the most cost-effective choices for improving the energy efficiency of your home. Adequate loft insulation can ultimately help reduce heat loss and lower your energy bills, helping keep your home cosy in the winter and cool in the summer, as well as helping keep your energy bills down. Ignite Property Group is committed to helping homeowners upgrade their homes to be more energy efficient, and within this blog, we will guide you through the process of calculating how much loft insulation you will need for your home. 

How Much Loft Insulation Do I Need?

  • Step 1: Measure Your Space

The first step to insulating your loft is taking the time to measure the width and length of your space to calculate the square footage. This is arguably the most important step in the process as it will determine how many loft rolls you require. Once you’ve measured both the length and width of your space, multiply the two values together to calculate the square footage as below. Alternatively, head over to our handy calculator which will do all the hard work for you. 

Square Meterage = Length (m) x Width (m) 

e.g 30m (length) x 20m (width) = 600 square feet

  • Step 2: Selecting the Right Insulation

At Ignite Property Group, we have spent significant time researching the best insulation available for lofts. As such, when we insulate properties, we use Knauf loft rolls and we are now proud to be offering this product to our customers to purchase directly for self-insulation. These rolls come partially perforated, providing the flexibility to be used between joists and are easy to trim or tear to the appropriate size. Regardless of where your joists sit in your loft space, you can easily customise the insulation to fit, ensuring a snug and effective installation. 

  • Step 3: Calculate Your Insulation Thickness

The recommended, regulated thickness of loft insulation for optimal performance is 270mm. Calculating the amount of insulation material you need will depend on multiple factors. 

A. If there is existing insulation in your loft, we recommend checking the thickness and topping this up. For instance, many homes may already have 100mm loft insulation, in which case, you will require 170mm thickness loft rolls to bring it up to the regulated standard. 

B. If your home has no insulation, you will need to combine multiple layers of insulation to reach the 270mm standard as unfortunately, rolls are currently not sold in this sizing. If your loft space has no insulation at all, adding any level of home insulation will be an improvement and provide a level of insulation to improve energy efficiency. 

  • Step 4: Calculate the Total Amount of Insulation Material 

To help keep things simple, we have specified the m2 coverage per roll, over on our product descriptions. You can then simply take your total square meterage and divide it by the coverage of the roll you wish to purchase to find out how many you will need to purchase. To help with this, you can also use our calculator to keep things simple

  • Step 5: Allow Space for Ventilation 

Insulating your loft space is essential for energy efficiency, however, it’s vital to ensure proper ventilation. Without adequate ventilation, there is a risk that condensation and moisture will build up, leading to mould and potential damage. Make sure to keep an eye out for any soffit vents or other ventilation openings in your loft space and be cautious not to block them. 

Expert Advice for Loft Insulation

To make your home more energy-efficient, trust Ignite Property Group to provide expert advice and offer high-quality insulation materials – all tried and tested by our professional team. Improve your home’s energy efficiency this winter with our handy guide to calculating the right amount of insulation material for your space. Get in touch with our friendly team who will be happy to help with any queries you may have. 


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