Housing conditions and energy efficiency Households according to whether they have made improvements to thermal insulation or the heating system, by tenure status of the housing. Unidades: Horizontal percentages. ;Has made improvements to thermal insulation or the heating system;No improvements have been made and it is warm enough during the cold months;No improvements have been made and it is not warm enough during the cold months; Total;14,1;60,8;25,1; Property;16,1;61,9;22; Lease at market price;6,4;58,3;35,4; Lease below market price;8,7;53,5;37,8; Free assignment;12,4;57,2;30,3; Notas: Fuente: Instituto Nacional de Estadística