How to Make Your Windows Warmer: 5 Proven Methods

Introduction

Cold windows aren’t just uncomfortable — they also increase heating costs. Studies show that up to 40% of indoor heat is lost through poor-quality or old windows. In Kyiv, where winters can be harsh, this problem is especially relevant for apartment dwellers.

Fortunately, in most cases, you can improve window thermal insulation without a complete replacement. In this article, we’ll explore 5 proven methods to make your windows warmer in Kyiv.

Method 1: Replacing Seals

Rubber seals are the first line of defense against cold. Over time, they lose elasticity, crack, and stop providing a tight seal.

Signs of Worn Seals:

• Rubber has become hard or sticky
• Cracks or tears have appeared
• There are gaps between the seal and frame
• The sash doesn’t press tightly against the frame
• There are drafts when the window is closed

How to Replace Seals:

1. Determine the seal type

• D-shaped: most common, suitable for most windows
• P-shaped: has an adhesive base, easier to install
• Extruded: more durable, suitable for heavy loads

2. Measure the length

Measure the length of the channel where the seal goes, around the entire perimeter of the sash and frame.

3. Remove the old seal

Carefully pull the old seal out of the channel. If it’s glued, use a mild solvent to remove residual adhesive.

4. Install the new seal

Insert the new seal into the channel, starting from a corner. Don’t stretch it too tightly. Cut off excess length with scissors.

Tip: When buying a seal, bring a sample of the old one to match the identical profile. The wrong size won’t provide a tight seal.

Method 2: Hardware Adjustment

Often, drafts are caused by incorrect hardware adjustment rather than worn seals. Modern hardware allows adjusting the sash pressure against the frame.

What You Need for Adjustment:

• Hex key (usually 4 mm or 6 mm)
• Pliers (for some hardware types)
• Instructions from the hardware manufacturer (Roto, Maco, Siegenia)

How to Adjust:

1. Find the adjustment screws

Adjustment screws are located on the sash edge (usually in the lower and upper parts of the hinge).

2. Vertical adjustment

To move the sash up or down, use the screw in the lower part of the hinge. Turn clockwise to raise, counterclockwise to lower.

3. Horizontal adjustment

To move the sash left or right, use the screw in the upper part of the hinge.

4. Pressure adjustment

Some hardware types have an additional screw for adjusting pressure strength. Turn it to increase or decrease the sash’s pressure on the frame.

5. Check the result

After adjustment, close the window and check the seal. Place a sheet of paper between the sash and frame — if the paper pulls out easily, the pressure is insufficient.

Important: Don’t overtighten screws. Excessive tightening can damage the hardware or deform the sash.

Method 3: Applying Energy-Saving Film

Energy-saving films are an affordable and effective way to improve window thermal insulation without replacing the glass unit.

Types of Films:

1. Infrared (ITO) Film

• Reflects infrared heat back into the room
• Reduces heat loss through glass by 30-40%
• Doesn’t darken the room (transparent)
• Price: from 500 UAH per m²

2. Membrane Film

• Creates an additional air gap
• Improves thermal and sound insulation
• Can have tinting
• Price: from 300 UAH per m²

3. Regular Polyethylene Film

• Budget option for temporary insulation
• Creates an air gap between the film and glass
• Price: from 50 UAH per m²

How to Apply Film:

1. Surface preparation

Thoroughly wash the glass and frame. Remove dirt, dust, and grease. The surface must be dry and clean.

2. Cutting the film

Cut the film with a 2-3 cm margin on each side.

3. Application

• For adhesive films: remove the protective layer and carefully apply to the glass, smoothing bubbles with a soft cloth or rubber spatula.
• For non-adhesive films: use double-sided tape or magnetic strip for perimeter attachment.

4. Trimming excess

Cut off excess film with a sharp knife or scissors along the frame edge.

Tip: Apply film in the room at temperatures above +10°C. At lower temperatures, the film may not adhere well to the glass. If you need help with window insulation or glass unit replacement, contact UWS professionals in Kyiv.

Method 4: Slope Insulation

Slopes are the wall areas around the window. If they’re not insulated, cold penetrates through the wall and cools the window frame, even if the window itself is of good quality.

Why Slopes Matter:

• Heat loss through uninsulated slopes can account for up to 30%
• Cold slopes lead to condensation and mold
• Overall room microclimate deteriorates

Slope Insulation Methods:

1. Mineral Wool + Plaster

• Most effective method
• Use basalt wool 30-50 mm thick
• Cover with plaster and paint
• Cost: from 800 UAH per window

2. Foam Board + Plaster

• Cheaper option
• Use foam board 20-30 mm thick
• Cover with plaster reinforced with mesh
• Cost: from 600 UAH per window

3. Thermal Plaster

• Simplest method to execute
• Special plaster with thermal insulation additives
• No additional insulation needed
• Cost: from 500 UAH per window

4. PVC Panels

• Fast installation
• No plastering or painting needed
• Cost: from 1,000 UAH per window

Method 5: Glass Unit Replacement or Addition

If your window has a single-chamber glass unit without energy-saving coating, replacing it with a double-chamber unit with a low-emissivity coating will significantly improve thermal insulation.

Improvement Options:

1. Glass Unit Replacement

• Replace single-chamber with double-chamber glass unit
• Add energy-saving coating (ITO or Low-E)
• Can add noise-reducing glass
• Cost: from 3,000 UAH per glass unit

2. Installing an Additional Glass Unit

• An additional frame with glass is installed on the existing window
• Creates a “triple glazing” effect
• Doesn’t require replacing the main window
• Cost: from 5,000 UAH per window

3. Applying Energy-Saving Film

• Cheapest option for improving the glass unit
• Reduces heat loss by 30-40%
• Cost: from 500 UAH per m²

Efficiency Comparison:

Tips for Choosing a Method

For those who want to save money:

• Start with changing seals and adjusting hardware
• Add energy-saving film
• Insulate the slopes

For those who want maximum effect:

• Replace the glass unit with a double-chamber energy-saving one
• Insulate slopes with mineral wool
• Install ventilation valves

For those planning renovation:

• Do comprehensive insulation: seals + hardware + slopes + glass unit
• Consider replacing the entire window if it’s old (over 15-20 years)

Conclusion

Making windows warmer can be done in various ways — from budget options (seal replacement, film) to major work (glass unit or full window replacement). The method you choose depends on the condition of your windows, your budget, and the desired result.

Key recommendations:

• Start with diagnostics: identify exactly where heat is being lost
• Use a comprehensive approach
• Don’t skimp on materials
• Consult specialists when needed

UWS offers window diagnostics and insulation services. Our specialists will help determine the optimal method and perform work with a warranty. Contact us for a free consultation in Kyiv. We perform window installation, window repair, balcony services, and door closer installation.