/
Restraint Straps (Domestic Floors)
Lateral restraint of the walls can be provided by the floor, the restraint must be provided parallel and perpendicular to the floor joists.
The type of restraint straps required and the centres at which they are placed depend on the joist end detail and region in which the house is built.
ROOF
3RD STOREY
The information we provide has been compiled using the minimum requirement from the Building Regulations 2010 approved document A, Scottish Building regulation domestic, NHBC standards, British Standards BS 5628-1:2005 Annex D and PD 6697:2019 Recommendations for the design of masonry structures to BS EN 1996-1-1 and BS EN 1996-2.
2ND FLOOR
2ND STOREY
1ST FLOOR
These have been issued as guidance only, the overall responsibility lies with the Building Designer.
1ST STOREY
GROUND FLOOR
3 STOREY HOUSE
For 3rd floor and above typically strap centres are reduced to 1.25m on all floors, please refer to the building standards or building designer for guidance.
All straps require a full storey of block work above to achieve the full 8kN declared load capacity.
Parallel Restraint
PSB strap with built in detail
— The strap should be nailed with a minimum of 8No 3.4x35mm Square Twist Nails into the joist bottom flange/chord
Floor Level
Detail
Region
Ground Floor
1st Floor
2nd Floor
Where joists have a minimum bearing of 90mm no additional restraint is required (additional PSB straps required each side of opening where openings exceed 600mm)
England & Wales
Built in
PSB straps required at 1.25m max centres
Scotland
As above
Please refer to page 141 for further information on PSB straps
PST strap with non–restraint hanger
— The strap should be nailed with a minimum of 8No 3.4x35mm Square Twist Nails into the joist top flange/chord
Floor Level
Detail
Region
Ground Floor
1st Floor
2nd Floor
Non–Restraint Hangers (JHI/JHIR/ RB–JHI/RB–JHIR)
England & Wales
PST or PSC required at 2m max centres
PST or PSC required at 2m max centres
PST or PSC required at 1.25m max centres
Scotland
Please refer to page 1 41 for further information on PST/PSC straps and table for the correct hanger / strap combination.
PSB strap with restraint hanger
— The strap should be nailed with a minimum of 8No 3.4x35mm Square Twist Nails into the joist bottom flange/chord
Floor Level
Detail
Region
Ground Floor
1st Floor
2nd Floor
No additional restraint required (additional PSB straps required each side of opening where openings exceed 600mm)
England & Wales
Built in
PSB straps required at 1.25m max centres
Scotland
As above
Please refer to page 141 for further information on PSB straps
The latest most up to date version will always be online and not in print or in downloaded pdf.
130
Technical support 01592 771132 / technical@itwcp.com / https://www.itwcp-offsite.co.uk
Made with FlippingBook Annual report maker