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Display window definition
NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
Display window – an area of glazing, including glazed doors, intended for the display of products or services on offer within the building, positioned at the external perimeter of the building and at
non-domesticenergyglazingConservatories without thermal separation
2.26NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
Where a new building incorporates a conservatory or similar highly glazed space which does not have thermal separation from the rest of the building it should be regarded as an integral part of the bu
non-domesticenergyglazingConservatories with thermal separation - General calculation
2.27NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
Where a conservatory, constructed as part of a new building, has thermal separation from the building, the TER and BER for the building may be calculated as if the conservatory is not present and the
non-domesticenergyglazingConservatories with thermal separation - Requirements when heated or cooled
2.27NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
However, irrespective of the conservatory being ignored for the purposes of calculating the TER and BER, where the conservatory is heated or cooled by a fixed building service either taken from the ma
non-domesticenergyglazingDemonstrating compliance with solar gains limits
2.70NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
Demonstrate that, for each space in the building that is either occupied or mechanically cooled, the solar gains through the glazing aggregated over the period from April to September inclusive, are n
non-domesticenergyglazingOpening areas – maximum glazing percentages
3.20NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
The total area of windows and rooflights in an extension should not exceed the values given in Table 3.1 unless a greater percentage of glazing is present in the elevations of the adjoining part of th
non-domesticenergyglazingTable 3.1: Opening areas in the extension
Table 3.1NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
Building type | Windows and personnel doors as % of exposed wall | Rooflights as % of area of roof Residential buildings where people temporarily or permanently reside | 30 | 20 Places of assembly, of
non-domesticenergyglazingRequirements for Non-Exempt Conservatories and Highly Glazed Spaces
3.28NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
Where a building is extended by a non-exempt conservatory or a sun-room or other highly glazed space, the extension should have – (a) thermal separation; (b) new controlled fittings that comply with t
non-domesticenergyglazingAlternative Approaches for Highly Glazed Extensions
3.29NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
Alternatively, the extension may be constructed in accordance with one of the approaches given in paragraph 3.17.
non-domesticenergyglazingHigh U-Value Windows and Doors Replacement
3.35NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
Where any existing window (excluding display windows but including roof windows or rooflights) or door (excluding high usage entrance doors) that separates a conditioned space from an unconditioned sp
non-domesticenergyglazingGlazing Area Limits for Material Change of Use
3.36NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
In a building subject to a material change of use, where the area of glazing is more than 25% of the total floor area of the building, either the area of glazing should be reduced to no greater than 2
non-domesticenergyglazingDefinition of controlled fitting
3.57NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
The term "controlled fitting" in relation to a window, roof window, rooflight or door means the unit as a whole (i.e. it includes the frame). Consequently, the replacement of a broken window pane is n
non-domesticenergyglazingPerformance standards for windows, roof windows, rooflights and doors
3.58NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
Where windows, roof windows, rooflights or doors are to be provided, they should be draught-proofed units whose area-weighted average performance is no worse than that given in Table 3.2. When replaci
non-domesticenergyglazingAlternative performance standard for replacement windows in buildings requiring external appearance preservation
3.59NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
Where, because of the need to maintain the external appearance of a building, replacement windows are unable to meet the standards given in Table 3.2, the replacement windows should have a centre pane
non-domesticenergyglazingconservationU-value calculation methods
3.60NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
U-values should be calculated using the methods and conventions given in BRE Report BR 443 Conventions for U-value calculations, and should be based on the whole unit (e.g. in the case of a window, th
non-domesticenergyglazingU-value assessment position for roof windows and rooflights
3.61NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
The U-values for roof windows and rooflights given in this Technical Booklet are based on the U-value having been assessed with the roof window or rooflight in the vertical position. Where a unit has
non-domesticenergyglazingRelaxed U-value for glazing in buildings with high internal heat gains
3.62NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
In some buildings with high internal heat gains, a less demanding U-value for glazing may be an appropriate way of reducing overall CO2 emissions. Where this can be demonstrated by calculation, the av
non-domesticenergyglazingStandards for controlled fittings
Table 3.2NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
Fitting Standard Windows, roof windows and glazed rooflights(1) 1.8 W/m2.K for the whole unit Alternative option for windows in buildings that are essentially domestic in character(2) A window energy
non-domesticenergyglazingLimitations on enlarged or new windows, doors and rooflights
3.64NI-wide·Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings
If a window, pedestrian door or rooflight is enlarged or a new one created, the total area of windows, pedestrian doors and rooflights expressed as a percentage of the total floor area of the building
non-domesticenergyglazing