How Rooflights Perform in Winter? Secrets You Need to Know!
Many homeowners worry that rooflights might let precious warmth escape during colder months. The reality? Modern rooflights keep homes cosy whilst flooding rooms with natural daylight, but only when you select the proper specifications.
Do Rooflights Make Homes Colder in Winter?
Not when properly specified. Quality rooflights with double or triple glazing achieve U-values ranging from 0.8 to 1.6 W/m²K. UK Building Regulations require a maximum of 2.2 W/m²K, so well-specified rooflights easily meet these standards.
What Makes Rooflights Energy Efficient in Winter
Double or Triple Glazing
Double glazing features two layers of glass with a gap between them. Triple glazing adds a third pane. These gaps contain argon gas, which prevents thermal loss far more effectively than standard air.
Triple glazing can reduce thermal loss by up to 40% compared to standard double glazing, making it an excellent investment for homes in colder climates.
Thermal Breaks in the Frame
Aluminium frames offer strength and slim profiles, but aluminium conducts warmth quickly. Without protection, thermal energy escapes directly through the frame.
Thermal breaks solve this problem. They are strips of polyamide material built into the frame that block thermal transfer. Quality rooflights feature multiple thermal breaks plus foam insulation between them, keeping the interior surface warm whilst the exterior stays cold (exactly what you want).
Low-E Glass Coating
Low-E (low-emissivity) glass features an invisible coating that reflects thermal energy back into your room whilst permitting daylight through. Think of it as an invisible thermal blanket on your rooflight.
How to Prevent Condensation on Rooflights
Condensation occurs when warm, moisture-laden air contacts cold glass. You'll notice it most after cooking or showering.
Why It Matters
Water droplets are not merely annoying. Over time, they damage paint, plaster and timber around your rooflight.
Simple Solutions
Use extractor fans. A single shower releases 1.5 litres of water vapour into the air. Extract it before it reaches your rooflight.
Maintain thermal breaks. They prevent glass from becoming too cold, stopping condensation from forming in the first place.
Passive Solar Heating Benefits of Rooflights
South-facing rooflights capture sunlight and convert it to passive solar warmth. This natural heating works even on cloudy days and rooflights provide at least twice as much daylight as same-sized vertical windows.
Position matters. South-facing rooflights capture the most winter sun. East-facing installations catch morning rays. North-facing rooflights deliver steady illumination but less passive warmth.
Choosing the right position is essential for maximising both warmth and following current rooflight trends.
Winter Maintenance Checklist for Rooflights
Clean Your Glass (September/October)
Dirt blocks up to 25% of natural daylight. Less illumination means your room feels darker and colder. Clean both surfaces before winter sets in.
Check the Seals
Look for gaps or cracks around the frame. Push gently on the rubber seals (they should spring back). Worn seals permit draughts in and warmth out.
Clear Gutters Nearby
Blocked gutters overflow during heavy rainfall. Water can pool around your rooflight and seep through tiny gaps in the flashing.
Choosing the Right Rooflight for Winter Performance
- Whole-unit U-value below 1.6 W/m²K (request the complete unit value, not just the glass)
- Argon gas filling between glass panes
- Multiple thermal breaks in the frame
- Low-E coating on the glass
- Quality weatherproof seals
Professional installation matters. Poor fitting creates gaps where thermal energy escapes, undermining even the best rooflight's performance.
Final Thoughts
Modern rooflights will not make your home cold when you choose wisely. Look for triple glazing, thermal breaks and Low-E coating. Maintain proper airflow to prevent condensation. Clean glass and inspect seals before winter arrives.
Done right, rooflights bring natural illumination and passive warmth into your home throughout the coldest months. For guidance on specifications suited to your property, trusted UK providers such as Rooflights and Skylights UK can help you make the right choice.