Cold Roof Height Myth?

Always contact me if you need help
📤[email protected]
📞Pick up the phone 07802300099

🏠 This is something that comes up all the time when people are having loft conversions or rear extensions built.

A customer will call me and say:
“We’re doing a cold roof because the builder said we’ll gain more height.”
Straight away, alarm bells start ringing.
In this video, I explain the real difference between a properly built warm roof and a properly built cold roof, using real examples and real measurements.
📏 The truth is, the height difference between warm roof and cold roof construction is often far smaller than people are led to believe.
And once you take into account correct ventilation voids, detailing, and skylight requirements, the so-called “height saving” can disappear completely.
What this video covers:

✅ The real height build-up of a proper warm roof construction
✅ The real height build-up of a proper cold roof construction
✅ Why cold roofs are harder to build correctly
✅ Why cold roofs usually cost more
✅ Why ventilation is critical (and where it often goes wrong)
✅ The common mistake builders make at wall plate height
✅ Why skylights make cold roof detailing even more complicated
✅ Why Building Regulations generally favour warm roof construction

Key point:

⚠️ A cold roof is NOT the easy option.
It is more complicated, more time-consuming, and far easier to get wrong.
If it’s not built perfectly, you can end up with:
❌ condensation issues
❌ poor airflow and blocked ventilation
❌ damp timbers
❌ mould risk
❌ expensive future repairs

This is exactly why I regularly see problems with cold roof constructions during roof inspections and roof surveys.

If you’re planning a loft conversion or extension:

📌 Don’t just accept “cold roof is better because it saves height” without seeing the actual measurements and understanding the construction details.
A warm roof is often the simpler and more reliable option when built correctly.

Need advice?

📸 If you need help, feel free to get in touch and send me photos, drawings, or measurements.
I carry out professional roof surveys, roof inspections, drone roof surveys, and roof reports across London.
I also provide advice on roof repairs, new roofs, flat roofing, and leak investigations.

Contact details

For London Flat Roofing:
Always contact me if you need help
📤 [email protected]

📞 Pick up the phone 07802 300099
👤 Steven Dickinson

0:00 Cold Roof vs Warm Roof Explained
0:29 Why People Choose a Cold Roof
0:45 Warm Roof vs Cold Roof Height Comparison
1:48 Warm Roof Construction Build-Up (Measurements)
2:55 Cold Roof Construction Build-Up (Measurements)
3:52 The Real Height Difference (Warm Roof vs Cold Roof)
4:05 Why Cold Roofs Are Harder and More Expensive
4:38 Where Builders Go Wrong (Wall Plate Height Mistake)
5:20 Cold Roof Problems With Skylights and Ventilation
6:02 Why Building Regulations Prefer Warm Roofs
6:22 Final Thoughts and Advice / Get in Touch