Winter Mode in Windows – How to Set It and Why It Matters

Do your windows feel slightly drafty on cold days?

Or does your home stay cool even though the heating is running? This could be a sign that your windows are still set to summer mode instead of winter 
mode.

The good news: Most modern windows are equipped with an easy adjustment feature that allows you to increase or reduce the sash pressure against 
the gasket.

A small adjustment — but one that can noticeably improve indoor comfort and help reduce heating costs significantly.

1. What is the winter mode on windows and how does it work?

Modern windows are equipped with adjustable locking cams, commonly referred to as “mushroom cams.” These determine how firmly the sash presses against the frame. By simply rotating these cams, you can switch the window to winter mode (stronger sealing pressure) or summer mode (slight ventilation).

  • Winter mode – the cam is rotated so that the wider side faces the gasket → the sash presses more tightly against the frame, allowing less air to enter the interior.
  • Summer mode – the cam is rotated so that the narrower side faces the gasket → a small airflow is allowed, improving natural ventilation.

2. Why is it worth switching your windows to winter mode?

Benefits of winter mode:

• comfortably warm interiors without drafts,
• reduced heat loss → lower heating costs,
• no unpleasant cold sensation near the windows,
• improved overall comfort – especially in winter, when more time is spent indoors.

Summer mode, on the other hand, allows for natural ventilation without having to fully open the windows – ideal for hot days or in homes where moisture tends to build up quickly.

Why is it worth switching your windows to winter mode?
How can you check which mode your windows are set to?

3. How can you check which mode your windows are set to?

You can check this in just a few seconds:

Open the window and look at the side of the sash – you’ll find a slightly oval-shaped metal cam there.

Check which side of the cam is facing the gasket.

• wider side → winter mode
• narrower side → summer mode

Alternative method – on a cold day, place your hand near the edge of the window. If you feel a draft, the window is most likely set to summer mode.

How to switch your window to winter mode step by step?
It’s really simple – it takes less than a minute per window!

What you’ll need:

  • Allen key or Torx (sometimes… your fingers or a pair of pliers are enough),
  • Flashlight (to get a better view of the cams).

Instructions:

  • Open the window.
  • Locate the round locking cam (mushroom cam) on the hardware.
  • Gently rotate the cam by 90° until it changes position.
  • Close the window and press it lightly – it should close with slightly more resistance.
  • Important: Adjust all cams – in most cases, there are several along each side of the sash.

4. Do all windows have a winter and summer mode?

Even though most people focus on heating during winter, summer mode is just as important:

Benefits of summer mode:
• improved air circulation – especially on hot days,
• reduced risk of moisture buildup indoors,
• fewer allergens and dust mites – important for allergy sufferers and children,
• fresher indoor air without having to keep windows fully open all the time.

When should you call a professional?

Even though the adjustment is simple, it’s worth getting a specialist involved if:

• you have many windows or some are difficult to access (e.g. at height),
• the windows remain leaky despite adjustment,
• visible deformation or sash misalignment is noticeable.

The cost of such a service is low, and at the same time you receive 
a complete inspection of the hardware and seals.

FAQ – Answers to the Most Common Questions

Yes – each cam works independently. It’s worth checking and adjusting all pressure points.
No – this function is provided by the manufacturer and has no negative impact on the warranty.
Ideally twice a year – in autumn and spring.
No – the cams have a limited range of movement. In the worst case, the window will press too tightly or too loosely, but this can be easily corrected.

Switching your windows to winter mode is one of the quickest home hacks for a warmer living space and lower heating costs. It only takes a moment, and the difference is immediately noticeable.

It’s a good habit to make seasonal adjustment part of your routine – just like changing car tyres or swapping out seasonal clothing in your wardrobe.

Do all windows have a winter and summer mode?