Energy Efficiency
Renovation Refurb and Retrofit

Winter-ready home: 5 DIY jobs to keep your house warm and energy-efficient

James Francis
James Francis
November 1, 2023

Winter is on the horizon so now is a good time to complete quick DIY jobs around your home to help keep energy bills down and your house warm and cosy as temperatures drop.

Check your loft insulation

1) Have you got enough loft insulation? How thick should loft insulation be?

According to the Energy Savings Trust, 25% of heat is lost through the roof in an uninsulated home. And while most homes have loft insulation, not all homes have enough.

The Energy Savings Trust advises homes have at least 270mm of insulation in a loft or attic which could help save up to 1310kg of CO2 per year in a detached home compared to a space that’s uninsulated.

CHECK THICKNESS - Use a tape measure to check the depth of your insulation to make sure there’s at least 270mm. You should also measure it in a few places to ensure the depth is consistent.   

2) Is your loft insulation still working?

Not all insulation is built to last so even if your home has loft insulation, it’s also important to check it’s working properly. 

For insulation to be effective and deliver the energy-saving performance that helps keep bills down, its strength and dimensional stability are key. This is because air pockets inside help prevent heat transfer.

CHECK CONSISTENCY - Squashed and sagging insulation  has less air meaning less energy-saving capabilities. 

To prevent this, it’s important to consider a product that’s going to keep its strength and in turn, its thermal performance. ROCKWOOL stone wool is ideal for this as it  maintains its shape and density over time. In tests, it is proven to provide consistent performance – even up to 65 years – without a drop in its thermal properties. 

To check whether your loft insulation is working as it should, look for areas that might have sagged and as described above, check that the depth is consistent throughout the loft or attic. 

3) Are there gaps in your loft insulation?

Heat can escape through gaps and open joints so when inspecting your loft insulation look for areas where it might escape.

CHECK FOR GAPS 

4) Is there condensation in your loft? 

To prevent condensation, it’s important that ventilation is maintained at the eaves where loft insulation has been installed in buildings with cold roofs at ceiling joist level.  If there are signs of excessive condensation, seek advice from a professional tradesperson.

CHECK FOR CONDENSATION 

5) Is your loft access draught-proof?

As well as checking for gaps in your loft insulation, consider draught-proofing your loft access too as it is a cost-effective way to ensure you prevent heat loss. Consider insulating the loft hatch or door itself to fully seal the loft.

CHECK FOR DRAFTS

How to improve your loft insulation

If there are gaps, signs of sagging in your loft insulation and/or there’s less than 270mm, it is a good idea to install new loft insulation. 

The first layer (generally of 100 mm thickness) is rolled between the ceiling joists, which are normally spaced at 400mm or 600mm centres and two layers of 100mm thickness are then cross layered over the ceiling joists for a total thickness of 300mm. 

Products such as ROCKWOOL Thermal Insulation Roll are designed to make this installation process more straightforward as it is supplied as a pre-split twin roll, with two 100mm layers for coverage in between and over the rafters. This means upgrading a customer’s loft can be as quick as a morning’s work but with energy savings that are shown to last for over half a century. 

Trade Range - Thermal Insulation Range

How to install loft insulation

Watch how to install ROCKWOOL loft insulation to improve the energy performance of your home.

Looking for more loft / attic insulation advice? Visit our loft insulation section 

Article History

Our experts continually review and update our articles when legislation changes or new information becomes available. 

First published: 20/11/2020