Element Library

SAP 2012 http://www.bre.co.uk/filelibrary/SAP/2012/SAP-2012_9-92.pdf

Walls

Element description Source U-value (W/K.m2) K-value (kJ/K.m2)
Cavity wall
Uninsulated cavity brick The Whole House Book p180 1.30 ?
Uninsulated cavity lightweight block The Whole House Book p180 0.96 ?
Uninsulated cavity wall Historic Scotland in situ measurements p38 1.2 +- 0.1 ?
Insulated cavity wall Historic Scotland in situ measurements p38 0.3 ?
Cavity walls involving brick and block with external render (for 1919-1975) Energy Saving Trust (EST) 2004, table 2, via Historic Scotland p38 1.7 ?
Brick/block cavity walls with insulation (for 2003-present) Energy Saving Trust (EST) 2004, table 2, via Historic Scotland p38 0.3 ?
Brick/brick cavity wall with 105mm brick, 50mm airspace, 105mm brick and 13mm dense plaster CIBSE Guide (Anderson, 2006a, tables 3.49 and 3.50, via Historic Scotland p38 1.44 ?
Stone wall
Uninsulated 600mm stone wall finished with 'plaster on laths' Historic Scotland in situ measurements p38 1.1 +-0.2 ?
Uninsulated 600mm stone wall finished with 'plaster on the hard' Historic Scotland in situ measurements p31 1.6 ?
Uninsulated 600mm stone wall finished with plasterboard Historic Scotland in situ measurements p38 0.9 +- 0.2 ?
Traditional sandstone or granite dwelling with solid walls: stone thickness typically 600mm with internal lath and plaster finish (for the pre-1919 period) Energy Saving Trust (EST) 2004, table 2, via Historic Scotland p38 1.7 ?
600mm stonewall with a 50mm airspace and finished with 25mm dense plaster on laths CIBSE Guide (Anderson, 2006a, tables 3.49 and 3.50, via Historic Scotland p38 1.38 ?
Timber frame
Cavity of timber frame wall with 50mm insulation The Whole House Book p180 0.45 ?
with 100mm insulation (2002 UK) The Whole House Book p180 0.35 ?
Superinsulated 250mm insulation The Whole House Book p180 0.14 ?
Solid Brick
Solid brick 225mm The Whole House Book p180 2.20 ?
220mm solid brick wall with 13mm dense plaster CIBSE Guide (Anderson, 2006a, tables 3.49 and 3.50, via Historic Scotland p38 2.09 ?
220mm solid brick wall with 50mm airspace/battens and 12.5mm plasterboard CIBSE Guide (Anderson, 2006a, tables 3.49 and 3.50, via Historic Scotland p38 1.41 ?

Roof

Element description Source U-value (W/K.m2) K-value (kJ/K.m2)
Uninsulated loft The Whole House Book p180 2.00 ?
with 100mm insulation The Whole House Book p180 0.30 ?
Room in the roof 200mm (2002 UK) The Whole House Book p180 0.20 ?
Loft with 250mm insulation (2002 UK) The Whole House Book p180 0.16 ?
Superinsulated 300mm insulation The Whole House Book p180 0.12 ?

Floor

Element description Source U-value (W/K.m2) K-value (kJ/K.m2)
Timber floor uninsulated The Whole House Book p180 0.83 ?
with 150mm insulation The Whole House Book p180 0.25 ?
Superinsulated 250mm insulation The Whole House Book p180 0.14 ?
Solid floor uninsulated (average house) The Whole House Book p180 0.70 ?
with 100mm insulation (2002 UK) The Whole House Book p180 0.12 ?
with 100mm insulation (2002 UK) The Whole House Book p180 0.25 ?
Superinsulated 200mm insulation The Whole House Book p180 0.15 ?

Timber Windows

Element description Source U-value (W/K.m2) K-value (kJ/K.m2)
Single glazed The Whole House Book p180 4.80 ?
Double-low-E 12mm airspace (2002 UK) The Whole House Book p180 2.00 ?
Double-low-E Argon fill 16mm airspace The Whole House Book p180 1.70 ?
Triple-low-E Argon fill or double super low-E The Whole House Book p180 1.30 ?

Table 1e: Heat capacities for some common constructions (k-values) kJ/m2K

page 197: http://www.bre.co.uk/filelibrary/SAP/2012/SAP-2012_9-92.pdf)

Element description K-value (kJ/K.m2)
Ground floors
Suspended timber, insulation between joists 20
Slab on ground, screed over insulation 110
Suspended concrete floor, carpeted 75
Exposed floors
Timber exposed floor, insulation between joists 20
External walls - masonry, solid, external insulation
Solid wall: dense plaster, 200 mm dense block, insulated externally 190
Solid wall: plasterboard on dabs or battens, 200 mm dense block, insulated externally 150
Solid wall: dense plaster, 210 mm brick, insulated externally 135
Solid wall: plasterboard on dabs or battens, 210 mm brick, insulated externally 110
External walls - masonry, solid, internal insulation
Solid wall: dense plaster, insulation, any outside structure 17
Solid wall: plasterboard on dabs or battens, insulation, any outside structure 9
External walls - cavity masonry walls, full or partial cavity fill
Cavity wall: dense plaster, dense block, filled cavity, any outside structure 190
Cavity wall; dense plaster, lightweight aggregate block, filled cavity, any outside structure 140
Cavity wall: dense plaster, AAC block, filled cavity, any outside structure 70
Cavity wall: plasterboard on dabs or battens, dense block, filled cavity, any outside structure 150
Cavity wall; plasterboard on dabs or battens, lightweight aggregate block, filled cavity, any outside structure 110
Cavity wall: plasterboard on dabs or battens, AAC block, filled cavity, any outside structure 60
External walls – timber or steel frame
Timber framed wall (one layer of plasterboard) 9
Timber framed wall (two layers of plasterboard) 18
Steel frame wall (warm frame or hybrid construction) 14
Roofs
Plasterboard, insulated at ceiling level 9
Plasterboard, insulated slope 9
Plasterboard, insulated flat roof 9
Party walls
Dense plaster both sides, dense blocks, cavity or cavity fill (E-WM-1)* 180
Dense plaster both sides. lightweight aggregate blocks, cavity or cavity fill (E-WM-2)* 140
Single plasterboard on dabs on both sides, dense blocks, cavity or cavity fill (E-WM-3)* 70
Single plasterboard on dabs both sides, lightweight aggregate blocks, cavity or cavity fill (E-WM-4)* 110
Single plasterboard on both sides, dense cellular blocks, cavity (E-WM-5)* 70
Plasterboard on dabs mounted on cement render on both sides, AAC blocks, cavity (E-WM-6 or E-WM-7)* 45
Double plasterboard on both sides, twin timber frame with or without sheathing board (E-WT-1 or E-WT-2)* 20
Steel frame (E-WS-1 to E-WS-3)* 20
Party floors (k from above / k from below)
Precast concrete planks floor, screed, carpeted (E-FC-1)* 40/30
Concrete floor slab, carpeted (E-FC-2)* 80/100
Precast concrete plank floor (screed laid on insulation) ,carpeted (E-FC-3)* 40/30
Precast concrete plank floor (screed laid on rubber),carpeted (E-FC-4)* 70/30
In-situ concrete slab supported by profiled metal deck, carpeted (E-FS-1)* 64/90
Timber I-joists, carpeted (E-FT-1)* 30/20
Internal partitions
Plasterboard on timber frame 9
Dense block, dense plaster 100
Dense block, plasterboard on dabs 75
Floor/ceiling/between floors in a house (k from above / k from below)
Carpeted chipboard floor, plasterboard ceiling 18/9