2.1.5 Adding or increasing external insulation in roofs
Description
This measure consists in adding a layer of insulation to the exterior face of the roofs with the object of reducing their thermal transmittance. The measure is of great interest for 1 or 2-storey buildings. It should be initially rejected for high-rise buildings roofs or for which have a thermal buffer space, as lumbers or no conditioned spaces.
Benefits
Minimum interference to the users of the building
The height of the rooms on the top floor is not reduced
Surface temperature higher than the dew point of the indoor environment, sufficient to avoid condensation
All the thermal inertia is used
In sloping roofs, the external insulation enables the recovery as habitable of the under roof spaces, increasing the useful surface of the building
In flat roofs the insulation is useful to protect the waterproofing sheet, so the durability of waterproofing increases considerably.
Limitations
Normally, executing the intervention through the outside, it will affect all of the building not just a flat in particular. Therefore it will be required, prior to the intervention, the express agreement of the community of neighbours.
Economic assessment
Initial investment: around 15 €/m2
Payback: around 2 years
References and best practices
- Determination of optimum insulation thicknesses of the external walls and roof (ceiling) for Turkey’s different degree-day regions:
www.sciencedirect.com/science/article/pii/S0301421507001826 Tips for roof insulation: energyquarter.com/energy-saving/insulation/tips-for-roof-insulation/
CHARACTERIZATION
Environment or playable world:
Residential
Academic
Offices
All
Carried out by:
Public building users
Owners
Operators
All
Reduce consumption of:
Heating
Cooling
DHW
Lighting
Electric devices
Type of driver:
Physical environmental
Contextual
Psychological
Physiological
Social
Time framework:
- Short term
- Long term
Type of measure:
- Envelope
- HVAC
- DHW
- Lighting
- Electrical devices
- Other