2.1.10 Installation of efficient windows (double glazing with wood frames)
Description
This measure consists in the replacement of inefficient windows (e.g. aluminium frame without thermal brake and single glazing) for an efficient one with double glazing and wood frames. A typical transmittance of this type of windows is between U=1.9 W/m2K and U=3 W/m2K, better performance than inefficient windows which have a typical transmittance higher than 4 W/m2K.
Benefits
Airtightness improved
Limited condensation
Sound insulation
Safety
Reduce heat losses
Wood is the most natural material and allows that the walls sweat from the inside to the outside. The same properties of wood regulate humidity naturally inside of the building.
It allows the installation of any security system for preventing theft, which applies both in the enclosures (mechanical systems in doors and windows) and those who are connected to a central.
The majority of woods used are suitably treated against fire, ensuring a greater resistance than other non-combustible materials
Limitations
Double glazing cannot be repaired
During the summer months, trapping heat inside glass panes can lead to a suffocating and uncomfortable room
Wood is the material that more maintenance requires. It is recommended to varnish the external side every two years.
It is not advisable the use of wood window frames in buildings located in areas with strong wind and rain. These climatic conditions cause heavy wear on the material, hence increase the need to be repaired.
Other enemies of wood, such as solar radiation and the emergence of organisms (fungi and insects), can be treated with components such as resin or insecticides. It should be paid special attention to the moth. There are many chemicals against the emergence of the woodworm.
Economic assessment
The price is usually high. Energy costs are reduced.
Table 1. Cost savings of wood frames. Source: Elaborated by CIRCE.
Type of frame |
Total cost (10 m2 of windows and 6 months) | % saving |
Aluminium without thermal break |
1.27 €/day 410€ |
– |
Wood | 0.87 €/day
158€ |
62% |
References and best practices
Thermal convection in double glazed windows with structured gap: www.sciencedirect.com/science/article/pii/S0378778811001551
Low heat loss double-glazed windows: www.sciencedirect.com/science/article/pii/0360544287900429
Carbon footprint versus performance of aluminum, plastic, and wood window frames from cradle to gate: www.mdpi.com/2075-5309/2/4/542/pdf
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