How to check the thermal insulation of the roof?
Checking the thermal insulation of the roof is an important measure that helps save energy and improve home comfort. A well-insulated roof prevents heat from escaping in winter and keeps the home cooler in summer. This article covers how to check the thermal insulation of a roof and what to look for.
Why is thermal insulation of the roof important?
The thermal insulation of the roof is one of the most important factors for a home’s energy efficiency. A well-insulated roof:
- Reduces heating costs in winter
- Improves living comfort
- Reduces the carbon footprint
- Prevents the formation of moisture and mold
Steps for checking the thermal insulation of the roof
1. Visual inspection
Start by visually inspecting the attic or roof space. Look for insulation that is flattened, uneven, sagging or shows signs of moisture or mold, and make sure the insulation layer covers the whole roof evenly and does not block ventilation ducts. Uneven or flattened insulation is usually a sign that it is no longer working as well as it should.
2. Measuring insulation thickness
Measure the thickness of the insulation, for example with a tape measure or by drilling a small hole to check it. The recommended thickness varies by climate, but in Finland roof insulation of at least 30–50 cm is generally recommended; compare the measured thickness against current building regulations and recommendations.
3. Thermal imaging
A thermal camera is an effective tool for detecting heat leaks: it shows temperature differences in color, making it easy to spot places where the insulation is insufficient. This usually requires hiring a professional with the right equipment.
4. Checking for air leaks
Air leaks can significantly reduce the efficiency of the insulation. A professional blower door test pressurizes the building to locate leaks precisely; for a simpler check, a smoke pencil or incense stick held near seams, hatches and penetrations will reveal drafts by how the smoke moves.
5. Moisture check
Moisture reduces the effectiveness of insulation and can cause mold problems. Use a hygrometer to check the moisture content of the insulation, and if you find moisture, locate the source and fix it before it causes further damage.
When to call a professional?
Many checks can be done yourself, but professional help is worth calling in when:
- You notice significant damage or moisture
- You are unsure about the condition or thickness of the insulation
- You want a thorough thermal imaging survey or a blower door test
A professional can give more detailed recommendations and carry out any necessary repairs.
