The sustainable development tax credit has been modified by the 2014 finance law for certain work carried out in individual houses.

Expenditures for the acquisition of thermal insulation materials for glass walls are only eligible for the tax credit if they are carried out as part of a package of work, regardless of the taxpayer's income. These expenses must cover at least half of the glazed walls of the dwelling.
Expenses incurred for the acquisition of insulating shutters or entrance doors opening onto the outside will only be eligible for the tax credit if they are carried out as part of a package of work and by people of modest means.

For these expenses, a distinction must be made between those carried out in isolation and those carried out as part of a package of work.

Expenditures made in isolation

The tax credit is no longer available to taxpayers who carry out, in their individual house, work relating solely to the thermal insulation of glass walls or insulating shutters or entrance doors, except for people of modest means.
This restriction applies to expenses paid as of January 1, 2014.

Expenditures made as part of a package of work

The tax credit is open to taxpayers carrying out the expenses concerned, plus other work (strictly enumerated) carried out in the same year.
In order to benefit from this tax advantage, the taxpayer must carry out expenses falling into at least two of the following categories:

• - Expenses for the acquisition of thermal insulation materials for glass walls;
• - Expenses for the acquisition and installation of thermal insulation materials for opaque walls in order to insulate the walls;
• - Expenses for the acquisition and installation of thermal insulation materials of opaque walls for the insulation of roofs;
• - Expenses for the acquisition of boilers or heating equipment or hot water production running on wood or other biomass;
• - Expenses for the acquisition of equipment for the production of domestic hot water using a renewable energy source;
• - Expenses for the acquisition of condensing boilers, micro-cogeneration gas boilers mentioned and equipment for energy production using a renewable energy source or heat pumps, and expenses for the acquisition of equipment for electricity production using the radiative energy of the sun.