Class 2a Buildings / houses of single occupancy five storeys or less England & Wales and four storeys or less Scotland Timber Gable to Masonry fixing detail to cold roofs – raised gable wallplate
Cavity trays and firestops to be detailed by building designer Gable Panel
Breather membrane to face of gable panel
Insulation continued into gable panel
Cullen FT Timber frame wall ties Mortar bed Wallplate 38mm min- 75mm maximum depth Levels to be adjusted to ensure top of bracing inline with top of blockwork Cullen Gable Restraint Bracket (GRB) at maximum 750mm centres Cavity insulation shown for indicative purposes only - thermal bridging and SAP calculations to be plot specific
Roof insulation
Longitudinal truss bracing (depth can vary to suit blockwork level)
Level of truss wallplate
Solid blocking between truss and gable panel at horizontal restraint strap positions Gable Panel to wallplate fixing - Paslode 3.1mm dia x min 75mm long smooth shank nails at maximum 100mm centres Vertical holding down strap plugged and screwed to blockwork at maximum 1.8m centres, Cullen VRS-900-100
Cullen PFS-1500-100-B restraint straps fixed to longitudinal truss bracing / additional longitudinal bracing at maximum 1.25m centres with 8 no. 4 x 25mm steel screws
Gable Panel (with or without gable ladder)
Cullen PFS restraint straps fixed to solid timber noggins between trusses at maximum 1250mm centres with 3.4 x 35mm square twist nails, 8 no. to noggins and 4 no. to gable panel (2 no. top face & 2 no. cavity face)
Gable Panel (without gable ladder)
Truss profile
Cullen PFS restraint straps bedded in mortar joint between top of masonry and wallplate and fixed to longitudinal truss bracing maximum 1250mm centres with 8 no. 4 x 25mm steel screws
Bottom rail of gable panel
Continuous wallplate 38mm min-75mm maximum depth
1250mm max
1250mm max
1250mm max
Mortar bed
750mm max 750mm max 750mm max 750mm max
Cullen Gable Restraint Bracket (GRB) at maximum 750mm centres
Cullen VRS-900-100 fixed to top of bottom rail with 4 no. 3.4 x 35mm square twist nails
1800mm maximum
Vertical restraint strap plugged and screwed to blockwork at maximum 1.8m centres - Cullen VRS-900-100 installed to top of gable panel bottom rail
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