Single family house 1930

The design and basic starting data of the reference building for existing sin-gle family house from 1930 is described in the annex.

In the table below are listed the relevant insulation thickness and the related U-values. The cost for the different solutions is shown in the next table.

Single family house 1930. Insulation thickness in the building elements and the related U-value of the construction.

Level Loft Walls, cavity Walls, external Floor slap

mm W/m² K mm W/m² K mm W/m² K mm W/m² K

For district heating the price includes the removal of the old heating unit, the installation of the district heating unit and also the connection to the main pipes inclusive of meter.

New gas boiler

The new condensing gas boiler has an efficiency of 0,98 at full load and 1,07 at part load. The new boiler also includes new, well insulated DHW tank and new efficient control of the heating.

New air to water heat pump

The prices available are based on heat pumps tested at 7/35 °C. The figures in brackets in the table are for the normal test temperature set of 0/35 °C. In accordance with DS469 an air to water heat pump is required to cover the total heat demand down till an external temperature of -7 C without addi-tional heating from an electric heating element. If connected to a radiator heating system with a design supply temperature of 70 °C the nominal heat-ing power of the air to water heat pump at test temperatures should be at least 100 % higher than the design heat loss of the building at an external temperature of -12 C inclusive of the heating power needed for heating of domestic hot water.

The air to water heat pump has a COP at normal test temperatures of 4,10.

The heat pump is with on-off control. The relative COP at 50 % part load is 0,93 for the actually used 16 kW heat pump.

Loft

Prices are inclusive of removal of existing insulation. This is more cost effi-cient than relining of partly damaged, existing insulation.

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Windows

Windows are energy class B and A in accordance with the requirements in BR 18 for 2018 and 2020.

Natural ventilation

Air exchange rates in the case of natural ventilation are 0,30 l/s per m² gross floor area inclusive of infiltration.

Mechanical ventilation

The mechanical ventilation has an basic mechanical air exchange rate of 0,30 l/s per m² gross floor area. The heat recovery efficiency is 0,85 and the minimum inlet temperature is 18 ^oC. The specific power for air transportation, SEL is 1,00 kJ/m³.

Existing single family house 1930. Investment in the energy saving measures, maintenance costs and life time of the elements. Investments and cost in the table are exclusive of VAT. 25 % VAT is added in the calculations of financial perspective.

Building element Size, insulation or type

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In combination with mechanical ventilation the infiltration is 0,13 l/s per m² gross floor area.

Airing at summer

The air exchange rate in relation to airing at summer time is 3,00 l/s per m² gross floor area in average.

Solar cells, PV

The solar cell, PV system has a peak power of 165 Wp/m² and a system effi-ciency, Rp of 0,75. The cells are mounted at the roof with a slope of 20^o and a horizontal cut off of 10^o. The need to change the inverter due to shorter lifetime of the inverter compared to the solar panels is treated separately in the cost calculations.

The tables below and on next page list the packages of energy saving measures calculated for the existing single family house from 1930. Each package includes additional insulation on the loft, additional insulation on the external walls, additional insulation in the basement slap, windows with specified energy class and PV. For each of the packages the primary energy demand, the macro economical net present value and the financial net pre-sent value is shown.

Mechanical ventilation is not tested as measure in the single house from 1930, because it is known from the analysis of the new single house, that mechanical ventilation is not cost efficient.

For the single family house from 1930 with district heating there is a gap of 5

% between the renovation class 2 requirement in BR18 and the point of cost optimal. In relation to renovation class 1 PV is needed and there is a nega-tive gap of - 58 %

Existing single family house from 1930 with district heating. Energy saving measures, primary energy consumption, macro economical and financial net present value.

Code Loft

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For the single family house from 1930 with natural gas heating there is a gap of 4 % between the renovation class 2 requirement in BR18 and the point of cost optimal. In relation to renovation class 1 PV is needed and there is a negative gap of - 46 %

For the single family house from 1930 with heat pump heating there is a gap of 10 % between the renovation class 2 requirement in BR18 and the point of cost optimal. In relation to renovation class 1 PV is needed and there is a negative gap of - 49 %

Existing single family house from 1930 with natural gas heating. Energy saving measures, primary en-ergy consumption, macro economical and financial net present value.

Code Loft

Existing single family house from 1930 with heat pump air - water heating. Energy saving measures, pri-mary energy consumption, macro economical and financial net present value.

Code Loft

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