How To Insulate A Loft

Looking to insulate your loft? Read our useful guide on how to insulate a loft with useful tips to help you stay safe while doing so

Everything You Need to Know on How to Insulate a Loft

Insulating your loft space comes with many benefits, such as:

  •  Significantly lowering your energy bills
  •  Helping to keep your home warm
  •  Being kinder to the environment
  •  Quick and easy installation

An uninsulated loft can lose over a quarter of the heat generated within your home. If it is not insulated correctly, the hot air rises to the roof's top to easily escape. This can lead to a vicious and expensive cycle of constantly losing heat and needing to turn the heating on to replace that warm air that's lost. Having to keep your heating on in colder months can lead to costly energy bills; it also sucks the moisture out of the air and can cause dehydration, dry skin problems, and even sinusitis.

Insulating your loft, attic, or roof space is a simple and effective solution to trapping air in the home. It is also very long-lasting with good quality insulation having a 40+ year lifespan. The savings you'll make on your energy bills over this period means that insulating your loft pays for itself and then saves you money year upon year.  


Find out how to insulate a loft with our simple recommendations and considerations

Which Loft Insulation Should you Choose?

Insulating your loft should be a straightforward process providing it is accessible, and there are no issues with dampness or condensation. While you can hire a professional to insulate your attic, you don't need any special skills or tools, so many choose to do this themselves.

Rolls of mineral wool insulation are a common choice for those with regular loft joists. The insulation can be rolled out between joists in layers. The primary layer is placed between the joists, with a second layer added perpendicular to this, covering the joists and ensuring that the insulation is at the correct depth.

An alternative method is warm loft insulation. Here the insulation is fitted between and over the rafters rather than between the joists. For this process, rigid insulation boards are cut to size and slotted in, or foam insulation can be sprayed between the rafters. This is not a job recommended for someone without experience, and you will likely need to hire a professional to help you.

Insulating your loft- Some Considerations


Using your attic space for storage can be very handy. However, to do so, boards will be placed between the joists. If there are boards already in your loft or plan to do this, you will need to raise the floor level before insulating. This is so you can fit enough of the insulation between joists to make it useful. When raising the floor, make sure that there is ventilation between the insulation and the boards to ensure that condensation doesn't build up underneath the boards and cause damp and rot problems. The insulation shouldn't be squashed down either, as this will negatively affect its ability to prevent warm air from escaping. 


 An Additional Room

If you plan to use the loft or attic as an additional room in your home, then the walls between the room and the unheated space must be properly insulated. Otherwise, the room will be extremely cold. You can insulate sloping ceilings and vertical walls in much the same way as you would a warm roof with an additional layer of plasterboard inside the insulated area. If the ceiling is flat, this can be insulated in the same way as a regular loft. This should be done by a professional. 


Hard to Access Spaces

Suppose your attic or loft isn't easily accessible. In that case, it is possible to hire a professional who will use special tools to blow the insulation into the right spaces to be effective. Options for insulation materials using this method include mineral wool fiber, treated cellulose, or polyurethane foam.


Flat Roofs

While insulating a flat roof from underneath can be done, this may lead to condensation issues. Therefore if you want to insulate a flat roof, it is best to tackle this from above. Rigid insulation boards can be put on top of the roof, either on the timber roof surface or the weather-proof layer. Timing this for when the flat roof needs replacing can be the most efficient way of doing this as now insulation must be completed in line with building regulations. 


Cold Lofts

Because insulation acts as a barrier between warm living spaces and the colder roof area, installing insulation will make your loft space colder. If you already know of damp problems in the area, it is vital to consider adding additional ventilation not to worsen after the insulation has been installed. Fixing damp problems before insulating is the best course of action.

It is also essential to be aware of your water tank and pipes, which could freeze in the colder space. Insulating around the pipes and tank will prevent this from occurring. Cold draughts could also escape into your home via the loft hatch, so adding some material around hatch edges to avoid this is also a good idea. 


Final Considerations for Insulating Your Loft

Remember, insulating your loft yourself can be a great DIY project. However, this is only a smart move if you are confident about the job, can access your roof space easily, and aren't aware of any problems that could make installation difficult. Our tips and guide on how to insulate your loft are only a guide, it's always best to employ a professional's help and can find a lift of experienced professionals who follow a strict code of practice via The National Insulation Association.