Bracing requirements for trussed rafter roofs.
Nhbc roof truss bracing.
7 2 08 bracing of mono pitch roof trusses 7 2 09 pitched roofs bedding verge undercloaks 7 2 10 attic trusses bracing 7 2 11 pitched roofs to garages holding down straps 7 2 12 roofng underlay at eaves level 7 2 13 ventilation of small roofs.
Additional bracing may be needed in exposed areas.
Nhbc standards chapter 7 1 flat roofs and balconies.
Details of bracing requirements.
List of chapters index.
Fixing to longitudinal bracing members using eight 25mm x 4mm steel screws evenly distributed along the length of the strap figure 2.
7 2 15 ventilation vapour control and insulation.
7 2 9 bracing for trussed rafter roofs.
7 2 11 support for equipment.
Chapter 7 2 2003 amendments to the standards 2003 source.
The layout of trusses and associated items.
Balcony drainage timber balconies and terraces revised october 2018 nhbc standards chapter 7 2 pitched roofs.
Appendix 7 2 f sizes and spacing of tile battens.
Nhbc standards 2020.
7 2 9 bracing for trussed rafter roofs trussed rafters shall be suitably braced to support applied loads and self weight without undue movement.
Appendix 7 2 e tank support details.
7 2 10 strutting for attic trusses and cut roofs that form a floor.
The roof should be braced using at least 100mm x 25mm timber.
To accommodate hatch openings or chimneys spacing may be increased to a maximum of twice the nominal spacing.
Trussed rafter roofs should be braced in accordance with table 1 in appendix 7 2 c unless the roof is designed and braced in accordance with bs 5268 3 or pd 6693 2 when published.
All bracing should be twice nailed with 3 35mm 10 gauge x 65mm long galvanized round wire nails to every trussed rafter it crosses and to the wallplate.
Diagonal bracing to double hipped roof plasterboard fire resisting ceiling in contact with single leaf masonry use of nail guns for fixing trussed rafter bracing.
Vertical and suitably located where necessary temporary bracing should be used to maintain spacing and to keep trusses vertical evenly spaced at maximum 600mm centres.
The minimum bracing requirements are shown in appendix 7 2 c.
Hips and valleys details of girder trusses multiple trusses and diminishing trusses including how they are to be fixed together and supported on truss shoes layboards or similar.
All timber bracing to trussed rafters should be at least 100mm x 25mm in section and twice nailed to each trussed rafter and to the wallplate.
For the purposes of this chapter the guidance and use of standard trussed rafter bracing does not apply to homes on or near exposed sites e g.
Alternatively 100mm x 25mm timber members fixed over four trusses and nailed in accordance with clause 7 2 9 can be used where the position of the strap does not coincide with a longitudinal binder.
7 2 14 underlay and sarking.
Where the maximum 600mm spacing cannot be achieved e g.
