Did you know that the average home loses up to 26 per cent of its heat through an un-insulated roof? A properly insulated loft prevents the heat from escaping and can reduce energy bills by as much as £175 per year*, whilst instantly boosting a property’s green credentials. Installing your own loft insulation is one popular job which can be completed in a day, no matter how amateur your DIY skills.
Here, energy saving advice website thinkinsulation.com proves just how simple it is to install loft insulation with a five-step plan.
1. Prepare – Before you start, work out how much insulation you’re going to need by measuring the loft space and the required depth by putting a ruler or tape measure down the side of the joists. Make sure you take into account any existing insulation. The government recommends installing insulation to a minimum depth of 270mm to ensure optimal performance. Don’t forget to measure the size of loft hatch, check that the loft is properly ventilated and consider pipes and wires within the space to ensure there are no potential dangers.
2. Dress for the job and make sure you have all the tools – As lofts can be dusty places before you begin it is best to cover your skin by wearing long sleeve clothing, gloves and a mask. Ensure you have the correct tools to hand – you’ll need a flat wooden board that you can lay across the joists and kneel on when laying insulation. Don’t forget to make sure you have a sharp utensil such as a large bladed knife available to cut the insulation blanket or loft roll to size if required.
3. Start Insulating – Now you’re ready to begin insulating! Start at the corner furthest away from the loft hatch ensuring that the wall plate is covered and work towards the centre of the loft. Tuck the ends of the roll into the eaves but don’t completely block them. You will need to lay a base layer to a depth of 100mm between the joists and leave an air gap of at least 5cm at the eaves (between the insulation and the roof felt) to ensure that there is sufficient airflow across the loft space to prevent condensation forming.
4. Layer Up – Once you’ve laid the initial layer of insulation (100mm), you’ll need to lay an additional layer (170mm) to give a total depth of at least 270mm. This second layer should be laid at right angles at the joists – this is called ‘cross layering’ and really makes a difference to the overall thermal performance. At this stage take extra care, working across the loft, it’s also important to remember that you will be covering joists, so be careful not to lose your footing as you go!
5. Review your work – Once the insulation is laid stand back and critique your job. Make sure that electric cables are lifted up and placed on top of the insulation and that recessed lights have a minimum 75mm clear airspace all around them to prevent them from overheating. If you have a water tank in the loft make sure that there isn’t any insulation underneath it – instead wrap around an insulated tank jacket around it.
*Based on an un-insulated loft being insulated to a depth of 270mm