Martin Lewis’ 4pm rule could help keep your home warmer and energy bills down

With energy bills putting pressure on household budgets, many Brits are searching for simple ways to stay warm this winter without spending a fortune – and Martin Lewis has a surprisingly easy tip

With energy bills continuing to put pressure on household finances, many Brits are looking for simple ways to keep their homes warm without sending their bills soaring. Thankfully, Martin Lewis has shared a simple trick that could help households keep their homes warmer for cheaper this winter – and it involves making one small change at around 4pm.

The MoneySavingExpert founder regularly shares advice designed to help people cut their household costs, from his website and social media channels to his appearances on ITV’s Martin Lewis Money Show Live and the BBC. One of his winter tips is easy to follow and could even help delay the moment you need to switch your heating on.

Martin Lewis’ 4pm rule

Lewis previously shared his advice on his ITV show, explaining how households can use their curtains strategically to help keep heat inside their homes. His advice is simple – keep your curtains open while the sun is shining, then close them once it gets dark.

Speaking to viewers, he said: “Use tactical curtains. When the sun is shining, it is letting light and heat into the house, so you want the curtains open.

“When it gets dark, it’s not, so you want to keep the heat in by closing the curtains. I know we all know that, but doing it rigorously can help insulate, especially if you line it with a fleece.”

The tip was originally shared in November 2022, but MoneySavingExpert has confirmed that the advice remains relevant.

Why you should close your curtains at 4pm

As the days get shorter, darkness arrives increasingly early, meaning there’s less natural warmth coming through your windows. For example, sunset is around 4.14pm on November 15, while by November 30 it is closer to 3.55pm.

That means getting into the habit of closing your curtains as daylight fades could help prevent some of the warmth inside your home from escaping through the windows. Curtains act as another barrier between the warm air inside your home and the colder glass.

Warm air naturally moves around a room through convection. Air next to a cold window cools down, becomes heavier and sinks, while warmer air is drawn towards the window.

Closing the curtains helps create another layer between the room and the cold glass, reducing the movement of warm air around the window.

How to make your curtains more effective

You don’t necessarily need to splash out on expensive thermal curtains to try the trick. Lewis has previously suggested using inexpensive fleece as a lining for existing curtains, which can provide another insulating layer.

He said there are plenty of guides online showing how to do this cheaply yourself, but households should make sure any fleece or other material used is fire-resistant before attaching it to curtains.

For those who can afford to invest, thicker or thermal-lined curtains are another option. Fleece works in a similar way to layers in a winter coat, creating pockets of air that can help slow down heat transfer.

Other ways Martin Lewis suggests saving energy

The 4pm curtain trick is just one of a number of energy-saving suggestions associated with Lewis and the MoneySavingExpert team. Other tips include fitting reflective panels behind radiators to help direct heat back into the room and tackling draughts around windows and doors.

Lewis has also regularly promoted the idea of “heat the human, not the home” – using targeted ways to keep yourself warm rather than heating the entire property when you’re only sitting in one or two rooms.

Simple changes such as wearing extra layers, using blankets or heating the room you’re actually using can potentially help households avoid wasting energy on empty rooms.

With colder weather approaching and household budgets still under pressure, making small changes to how and when you use energy could help keep some of that expensive heat inside your home.

Your advice

Sharing their own tips for keeping heating costs down, one user on Reddit’s Life Hacks thread suggested using clear packing tape to tackle draughty windows.

They wrote: “If you have a draft coming from an old double hung or sliding window, simply take some clear packing tape and try to cover up the gaps that make it drafty. It’s not going to completely keep the cold out, but it will certainly slow it down considerably.

“Did this a few times to some apartment windows where the landlord was too cheap to fix the windows and you could feel the room warm up almost immediately.”

Another added: “If your home doesn’t have central heating, you can heat only the most insulated rooms where people spend most of their time.

“The first month in my house, I heated every room and spent 4x the energy I’ve been using since. Invest in a couple pairs of thermal hiking socks.

“If you’re sitting at the computer, stand up and bounce every once in a while to keep the blood flowing in your legs and feet.”

A third Reddit user suggested making the most of the heat produced when cooking, writing: “Electric ovens are not vented (not sure about gas) therefore the heat from your oven will radiate into the room whether or not the door is open.”