Window Adjustment for Winter and Summer: Complete DIY Guide [2025]
Every homeowner knows this frustrating moment perfectly. You close the window on a cool evening, yet you still feel a subtle but distinct draught of cold air. The window handle turns with increasing resistance, and the sash begins to scrape against the frame. These are precisely the signals that your windows need seasonal window adjustment – a simple but crucial maintenance procedure.
Window adjustment for winter and summer isn't a whim, but a necessity arising from the laws of physics. In this guide, we'll show you step by step how to care for your windows independently, when it's worth doing, and when it's better to trust professionals. Thanks to practical knowledge from our 30 years of experience in the windows and doors industry, you'll learn to save on heating bills and extend the lifespan of your windows.
Why is Window Adjustment a Necessity, Not an Option?
Before you reach for tools, it’s worth understanding why window hardware adjustment is needed at all. This isn’t a product defect, but a natural consequence of physics laws acting on every building.
Physics of Temperature Changes and Material Expansion
The foundation of the problem is thermal expansion of materials. Every window element – PVC profiles, aluminium, steel reinforcements, and even window seals – changes its dimensions under temperature influence. In summer, materials expand; in winter, they contract.
PVC profiles are characterised by relatively large linear expansion. This means that a long element, such as a window frame, can extend by several millimetres in summer compared to its winter dimensions. Modern windows with Winkhaus hardware are designed to compensate for these changes through appropriate steel reinforcements and thermal breaks.
Despite advanced technology, the cyclical “working” of materials throughout the year inevitably leads to microscopic shifts of the sash relative to the frame. A window perfectly fitted in July may prove too loose in January.
Impact on Airtightness and Energy Savings
These seemingly minor, millimetre changes have a direct impact on the window’s most important winter function – window airtightness. Loss of airtightness leads to uncontrolled draughts, and even a small gap becomes a thermal bridge.
The effects are twofold. First, we experience discomfort from cold draughts. Second, the heating system must work more intensively, which directly translates to higher energy bills. Window compression adjustment, commonly called setting the winter mode for windows, allows you to regain full airtightness and minimise energy losses.
Protecting Hardware from Premature Wear
Window hardware, particularly advanced systems like Winkhaus activPilot, are precisely engineered mechanisms consisting of numerous moving elements: espagnolettes, corner drives, window hinges, and locking cams.
When a window is misadjusted, every attempt to close it “by force” causes enormous overloads within the mechanism. Locking cams strike against keeps instead of smoothly engaging them, and window hinges work at improper angles. Such operation leads to accelerated wear and can cause permanent damage to expensive components.
When Should Windows Be Adjusted? Seasonal Maintenance Calendar
The best approach is PVC window maintenance twice a year – late autumn before the heating season and early spring.
Optimal Adjustment Times (Autumn/Spring)
Window adjustment for winter should be carried out in October or November, when temperatures permanently drop below 10°C. This is the moment when materials begin to contract and we need maximum airtightness.
In spring, when temperatures consistently exceed 15°C (59°F), it’s time to switch windows to summer mode for windows. This reduces compression, enabling micro-ventilation and preventing excessive loading of window hardware during material expansion.
Signs Indicating Need for Adjustment
Don’t wait for set dates if you notice these symptoms:
Winter symptoms requiring adjustment:
- Noticeable draught with closed window
- Water vapour condensation on glass
- Increased heating bills
- Difficulty closing windows
Summer symptoms indicating excessive compression:
- Window handle turns with great resistance
- Sash “snaps” when opening
- Excessive wear of window seals
Differences Between Winter and Summer Modes
Winter mode for windows is characterised by maximum compression of locking cams against window seals. This ensures the best airtightness but increases mechanism wear.
Summer mode for windows reduces compression, enabling controlled micro-ventilation. Air exchanges through an almost invisible gap, regulating humidity levels without causing noticeable draughts.
Diagnostics: Check Your Window Condition Before Adjustment
Before proceeding with Winkhaus window adjustment, you must accurately diagnose the problem. Just as a doctor doesn’t prescribe medication without examining the patient, you shouldn’t adjust a window “blindly”.
Paper Test – Checking Compression
This is the simplest method for checking sash compression against the frame. Open the window, insert ordinary paper between the sash and frame, then close the window and try to pull out the paper.
Result interpretation:
- Weak compression: Paper slides out without resistance – window is leaking
- Proper compression: Paper offers clear, even resistance
- Excessive compression: Paper tears or requires great force to remove
It’s crucial to perform this test at several points around the entire sash perimeter – bottom, top, and sides.
Candle Flame Test – Detecting Leaks
This method effectively detects even the smallest draughts. On a windless day, light a candle and slowly move the flame along all edges of the closed window. If the flame flickers, wavers, or leans, you’re dealing with a leak.
Visual and Audio Inspection
Open and close the window slowly, paying attention to:
Disturbing sounds during sash movement: friction, squeaking, grinding, or knocking indicate that a sash element is scraping against the frame or hardware.
Uneven gaps between sash and frame may indicate sagging or displacement of the sash.
Handle position in closed position should be perfectly vertical, with smooth rotation.
Symptoms and Solutions Table
| Symptom | Probable Cause | Solution | Difficulty Level |
| Draught with closed window | Insufficient compression | Compression adjustment on locking cams | DIY Basic |
| Sash scrapes bottom frame | Sash sagging | Window height adjustment | DIY Basic |
| Sash scrapes side frame | Lateral displacement | Lateral adjustment | DIY Intermediate |
| Resistance when turning handle | Excessive compression or lack of lubrication | Window hardware lubrication | DIY Basic |
| Window won’t close | Significant misadjustment | Comprehensive adjustment | Professional service |
Step-by-Step Window Adjustment – Instructions for Winkhaus Hardware
After proper problem diagnosis, you can proceed with Winkhaus activPilot window adjustment. These instructions are intended for persons with experience in technical work.
Important warning: Seasonal window adjustment is a maintenance procedure for which the user bears responsibility. Improperly performed adjustment may become grounds for warranty voiding. In case of doubts, contact a professional service.
Essential Tools and Materials
Basic tools:
- 4mm Allen key – for most height and lateral adjustments
- 2.5mm Allen key – for additional compression adjustment in some hinges
- Special Winkhaus HV-11 key – dedicated for adjusting octagonal locking cams
- Screwdrivers (flat and Phillips) for removing covers
Maintenance materials:
- Hardware oil (acid-free, e.g., machine oil)
- Technical grease (technical petroleum jelly or lithium grease)
Critical warning: Never use penetrating oil products like WD-40 for window hardware lubrication. These agents flush factory grease from mechanisms, leading to accelerated wear.
Compression Adjustment (Winter/Summer Mode) – Locking Cams
This is the most common and simplest adjustment, responsible for window airtightness.
Step 1: Open the window sash. On its side edge, you’ll find several (usually 3-5) protruding, movable elements – locking cams operating on the eccentric principle.
Step 2: Each locking cam has a marker – a dot or line indicating the current eccentric position.
Step 3: How to adjust windows for winter – turn each locking cam so the marker points towards the seal (inward). The thicker part of the eccentric will press the sash more firmly against the frame. The adjustment increases compression by approximately ±0.8mm.
Step 4: Set summer mode – turn the locking cams so the marker points outward. The thinner part of the eccentric will reduce compression force, enabling micro-ventilation.
Step 5: Neutral position (spring/autumn) – marker pointing up or down ensures standard compression.
Key tip: Set ALL locking cams around the sash perimeter to the same position.
Sash Height Adjustment – Bottom Hinge
We perform window height adjustment when the sash has sagged and scrapes the bottom frame edge.
Step 1: Open the sash and locate the bottom hinge. Remove the plastic cover.
Step 2: On the top surface of the metal hinge body, you’ll find an adjustment screw with a socket for 4mm Allen key.
Step 3: Insert the key and make the adjustment:
- Clockwise rotation = raise the sash
- Anti-clockwise rotation = lower the sash
Step 4: Adjust gradually, by quarter or half turns, checking the effect after each change. The adjustment range in activPilot hardware is ±3mm.
Lateral Adjustment – Bottom and Top Hinges
We perform this adjustment when the sash scrapes the side frame edge.
Bottom hinge adjustment: Step 1: With the sash open, locate the second adjustment screw on the bottom hinge, positioned laterally.
Step 2: Use 4mm Allen key:
- Clockwise rotation = move bottom of sash towards hinge
- Anti-clockwise rotation = move bottom of sash away from hinge
- Adjustment range: ±2mm
Top hinge (scissors) adjustment: Step 1: Open the sash to 90 degrees.
Step 2: Locate the adjustment screw on the scissors arm attached to the sash.
Step 3: Adjust the top corner position of the sash with appropriate key rotation.
Important note: Often corrections must be made to both bottom and top hinges so the entire sash moves parallel.
Hardware Lubrication and Maintenance – Secret of Longevity
Window hardware lubrication is as important an element as the adjustment itself. It ensures smooth mechanism operation for years and protects against corrosion.
Annual Maintenance Plan
Carry out comprehensive PVC window maintenance once a year, preferably in autumn before difficult winter conditions.
Four steps of annual maintenance:
- Hardware cleaning with dry, soft cloth or brush
- Fastening check – tightening loosened screws
- Moving parts lubrication with appropriate agents
- Seal care – cleaning and maintenance
Lubrication Points in Hardware
Hardware oil (one drop) apply to:
- All locking cams – pins and rolling surfaces
- Scissors mechanism (top hinge)
- Window hinges – rotation axes
- Corner drives and espagnolettes – moving metal elements
Technical grease (thin layer) apply to:
- Keeps on the frame that locking cams engage
After applying lubricants, open, close, and tilt the window several times to distribute the grease evenly.
Selecting Appropriate Lubricants
Use exclusively acid-free and resin-free oils – machine oil, sewing machine oil, or specialist hardware oil. For keep lubrication, lithium grease or technical petroleum jelly is ideal.
Seal Care
Window seals made from EPDM rubber require regular care:
- Cleaning with soft cloth with water and mild detergent
- Maintenance with silicone preparation that creates a hydrophobic layer protecting against moisture and UV radiation
When DIY Isn’t Enough? Problems Requiring a Specialist
Skillful recognition of your competence limits protects against costly errors and warranty loss.
Signs of Serious Faults
Red flags requiring professional intervention:
- Adjustment in extreme positions doesn’t help – possible installation error or window deformation
- Visible profile deformation – frame or sash bending
- Broken hardware elements – necessary replacement of damaged parts
- Window “falls” from top hinge – locking mechanism failure
- Completely worn seals – professional replacement required
Consequences of Improper Adjustment for Warranty
Seasonal window adjustment is treated as a maintenance procedure belonging to user obligations. The phenomenon of misadjustment from normal operation doesn’t qualify for free warranty repair.
Improperly performed adjustment may become grounds for warranty voiding of the entire product. If you damage hardware during self-adjustment, the manufacturer may refuse warranty repair.
Value of Professional BWS Service
An experienced technician with our 30 years of industry experience brings value extending far beyond mere adjustment:
Comprehensive diagnostics – identifying the original cause of the problem, not just the symptom Early wear detection– assessment of invisible component condition Access to original parts – guarantee of compatibility and reliability
We specialise in Winkhaus and MACO systems, offering professional service based on thorough knowledge of these technologies.
Savings and Comfort – Benefits of Regular Adjustment
An investment of several minutes in seasonal window adjustment brings measurable benefits throughout the year.
Real Impact on Heating Bills
Properly adjusted windows in winter mode can reduce heat losses by up to 15-20%. For an average home, this means savings reaching several hundred dollars annually on heating.
A leaky window is like a small window left wide open – cold air constantly flows inside, and the heating system must work more intensively, consuming more energy.
Improved Living Comfort
Window airtightness means not only savings but primarily comfort. Eliminating draughts means:
- Even room heating
- No unpleasant draughts
- Reduced condensation on glass
- Better acoustic insulation
Summer mode for windows ensures controlled ventilation, regulating humidity levels without causing noticeable draughts.
Extended Window Lifespan
Regular PVC window maintenance and window hardware lubrication can extend mechanism lifespan by up to 50%. Winkhaus hardware with proper care serves trouble-free for decades.
Neglecting maintenance leads to:
- Accelerated wear of locking cams
- Problems with window handles
- Premature hardening of window seals
- Costly repairs or replacement of entire mechanisms
Summary
Window adjustment for winter and summer is a foundation of home care, on par with heating system maintenance. Thanks to practical knowledge from this guide, you can independently ensure window airtightness, energy savings, and comfort for your family.
Remember the key principles:
- For serious problems, trust professionals
- Perform seasonal window adjustments twice yearly
- Regularly carry out window hardware lubrication
- Don’t delay PVC window maintenance
