Window replacement programme, Basque Country, Spain


The object of the project promoted by the Basque Government is to replace old and inefficient windows in residential buildings through grant programs, covering a maximum of 22% of the replacement cost. In any case, the maximum subsidy for each house is 1,200 Euro. The replacement program has been implemented in 6,765 households during 2010-2011.

Results and impacts

Start Date: 2010
End Date: 2011

Cumulative investment made by stakeholders: 8,250 kEuro/year
The replacement program has been implemented in 6,765 households
Heat savings: 11,200 MWh/yearElectricity savings: 4,800 MWh/year
Reductions of greenhouse gas emissions 4,754 t CO2e/year
Average grant: 22%

Aims and objectives of this sustainable energy action

The aim of the project is the promotion of the renovation of glazed enclosures in residential buildings with new elements with high-efficiency thermal performance. Glazed enclosures would be those windows and glass doors which separate heated rooms from the outside. The final objective, therefore, is the reduction of the energy consumption in the household sector. This project has also managed to stimulate the window manufacturer sector and carpenter's workshops.

This action is aimed at private owners. It has to be taken into account that most of the dwellings in the Basque Country are privately owned and most of them belong to the user.

Technical and financial implementation

The specific features of the new windows are designed to reduce energy consumption. In the technology based on double-glazing windows, the air or gas between the panels stops the conductive thermal energy from passing through the glass.

Two types of window frames can be installed: metal frame with thermal break and non-metal frame: wood-framed window, polyvinyl chloride (PVC), hybrid frame designs, polyurethane frames,...

On the other hand, the heat loss rate of the installed windows must be lower than 1.5 W/m2K for glasses with metal frames and lower than 2 W/m2K for glasses with non-metal frames.

Finally, the CE marking is required for the installed new windows.

Both the owners and the tenants of houses are able to accede to the grant. The dwelling must be located in the Basque Country and needs to be the main residence of the applicant.

Lessons learnt

In some cases window’s replacements are not carried out properly and there are also situations of people asking the subsidy without having any intention of changing windows. To avoid these failures in the conditions to access the subsidy, inspections are necessary to ensure that the replacement is done correctly.

The offered grant have proved to be enough to motivate an important number of owners to make the decision of facing the investment required to replace the window, achieving a reduction in the consumption of energy and an increase of the level of comfort.

How this action could be replicated

The renovation of windows and other glazed enclosures provides reductions of energy consumption but it also improves the comfort of the user, so it is not difficult to involve the citizens in this activity. The main barrier is the cost; the user sees the grants as an opportunity to improve his quality of life at a reduced cost, even if the grant is just 22% and the return of investment is low.

To carry out this program it has been necessary to make an adequate campaign for advertising. The consumers are provided with guidance in making decisions on how to choose energy-efficient windows and information on the benefits of efficient windows (energy and cost savings, comfort improvement, condensations...).


The project is aimed at private household owners, and the promoter is the Basque Government through the Basque Energy Agency-EVE.

Contact details

Ente Vasco de la Energía - EVE
Alameda de Urquijo, 36 - 1º. 48011, Bilbao, Spain
T: (34) 944 035 600

Álvaro Pérez de Laborda;

Further information