• 2 available credits
• Credits worth 1.33% points each
• Mandatory Element: No

Aim: To promote the most efficient use of a building’s footprint by ensuring that land and material use is optimised across the development.

Assessment Criteria:

Full ECO5 2010 Issue

• 2 available credits
• Credits worth 1.33% points each
• Mandatory Element: No

Aim:To promote the most efficient use of a building’s footprint by ensuring that land and material use is optimised across the development.

Assessment Criteria: This issue is assessed on a site wide basis. Credits are awarded where the ratio of combined net internal floor area to footprint area (as measured by the total net internal ground floor area of all dwellings on the site) meets the requirements defined below: Individual dwellings (i.e. detached, semi-detached and terraces, not individual flats) that are not subject to a Code assessment, can be excluded from the assessment of this issue

Full ECO5 2009 Issue

CIRIA

Government Planning Department

1. Where there is a mixture of houses and flats, to calculate the area weighted target ratio for the site, use the following formula:

For one credit:

Area Weighted Target Ratio = (Total NIFA Houses × 2.5) + (Total NIFA Flats × 2.5) / Total NIFA of all Houses and Flats

For two credits:

Area Weighted Target Ratio = (Total NIFA Houses × 3.2) + (Total NIFA Flats × 4.0) / Total NIFA of all Houses and Flats

2. The site wide ratio should then be calculated using the following formula and assessed against the above target ratio. Credits can be awarded where the ratio calculated using the following formula is greater than the target area weighted ratio as described in point 1 above. Site Wide Footprint to Floor Area Ratio = ( Total NIFA of all Dwellings / Total NIGFA of all Dwellings )

"Code for Sustainable Homes Technical Guide November 2010"

Net internal floor area The area of all habitable spaces, including the area taken up by halls, stairwells, cupboards, internal partitions, habitable loft spaces and basements. This also includes common areas of blocks of flats and apartment buildings, including stairwells, circulation spaces and entrance lobbies.

For semi-detached or terraced dwellings, this excludes the area of the party walls.

For flats, the floor area includes the party walls and separating walls to common areas.

Where residential accommodation is constructed above other occupied space such as shops or offices (garages or car parking would not be included), the floor area Eco 5: Building Footprint | 263 Eco of these spaces can be included within the net internal floor area of the dwelling provided the areas are directly beneath the residential space.

"Code for Sustainable Homes Technical Guide November 2010"

Also referred to as the building footprint, this is the area of land that is taken up by the permanent foundations of the dwelling (including any other outbuildings with permanent foundations that are associated with the dwelling), within the external walls of the building.

For this issue, this is measured as the total net internal floor area of the ground floor, excluding the area taken up by the external walls.

In blocks of flats, this also includes the area taken up by party walls and separating walls to common areas, with the exception of party walls to adjoining buildings.

For staggered dwellings, the footprint area equals the total net internal floor area of the floor with the largest plate.

Areas that normally count towards the footprint include conservatories, garages, permanent outhouses, fully enclosed permanent waste storage areas, communal garages or storage rooms and any other permanent buildings used by the occupants

• Areas that will NOT normally count towards the footprint include hard landscaping, semi-enclosed external spaces, pergolas and carports
• Garden sheds will not count unless they are built on a permanent solid foundation and are fitted out as habitable space with heating, lighting and power
• If a dwelling is raised above ground level on columns or other structures, the net internal ground floor area must be measured from the lowest floor of the dwelling
• Where other occupied spaces (e.g. non-domestic spaces such as retail and offices etc) form the ground floor or lower floors under a block of flats, the net internal ground floor area must be measured as the net internal floor area of the lowest floor of the block of flats.

"Code for Sustainable Homes Technical Guide November 2010"