STRAMIT RESIDENTIAL FLOOR FRAMING SYSTEM. p r o d u c t t e c h n i c a l m a n u a l DFF

Transcription

1 STRAMIT RESIDENTIAL FLOOR FRAMING SYSTEM p r o d u c t t e c h n i c a l m a n u a l DFF

2 STRAMIT RESIDENTIAL FLOOR FRAMING SYSTEM A suspended floor design solution for both single and two storey residential construction. C-JOIST IMPORTANT NOTICE AND DISCLAIMER The information contained within this brochure is intended for general use and information only. Before application in a particular situation, Stramit recommends that you obtain appropriate independent qualified expert advice confirming the suitability of product(s) and information in question for the application proposed. While Stramit accepts its legal obligations, be aware however that to the extent permitted by law, Stramit disclaims all liability (including liability for negligence) for all loss and damage resulting from the direct or indirect use, or reliance on, the information provided in this brochure. 2

3 CONTENTS PAGE INTRODUCTION SELECTION AND SPECIFICATION DESIGN AND CONSTRUCTION Design Load Criteria Load Areas Framing Connections and Support Balconies and Verandahs Post/Piers and Bracing INSTALLATION PROCUREMENT ADDITIONAL INFORMATION REFERENCES INTRODUCTION The Stramit Residential Floor Framing system is designed to address the needs of domestic house construction. A wide range of section sizes provides freedom in designing floor joists, bearers for most locations. The Stramit Residential Floor Framing System can easily be adapted to a variety of house designs. In addition, the Stramit Residential Floor Framing system has extended bearer options to provide larger span design possibilities. extended bearer spans available up to 8 metres Stramit C-Joist with (U-Beam shown) Extended Bearer The Stramit Residential Floor Framing System offers joist spans at 450mm centres ( metres) Stramit C-Joist Stramit C-Joist and Bearer U-Beam Extended Bearer The Stramit Residential Floor Framing System is only suitable for use in residential home construction. It is not intended, nor suitable, for use in any form of mezzaine commercial, institutional, industrial, agricultural or any other form of non-residential construction. If in any doubt contact Stramit to confirm the suitability of a given application. Stramit Joist Stramit Bearer 3

4 SELECTION AND SPECIFICATION Termite resistant Non combustible components Lightweight and easy to install Ideal for flat or sloping sites Fast track construction with engineered components Pre-cut and prefabricated components enable speedy construction, even on sloping sites Suitable for use on standard industry pier systems Dimensional stability Achieve true lines without warping Economical in materials and construction Delivers a finish without shrinkage cracks Will not warp or twist and remains stable for the life of the building Dimensions and Mass Table 1 STRAMIT C-Joist & Bearer Dimensions & Mass member section depth width lip thickness mass D W L t mm mm mm mm kg/m J J J J J J J C J Joist J J J J J J J B B B C B Bearer B B B D Stramit C-Bearer W Table 2 Materials Stramit C-Joist and Bearers are cold rolled formed sections manufactured from high strength steel in material thickness ranging from 1.0mm (G550 grade, 550 MPa minimum yield stress material) to 2.4mm (G450 grade, 450MPa minimum yield stress material), with Z350 zinc coating (350grams per square metre minimum coating mass) in accordance with Australian Standard AS1397. Other Stramit accessories, such as FCB3 brackets, extended bearer brackets and lateral end restraints, are made from 300 MPa or 450MPa steel with a minimum glavanised coating of 275 grams per square metre. Tolerances Stramit C-Joists and Bearers are supplied with a length tolerance of +0-10mm. Performance Stramit C-Joists STRAMIT Extended Bearer Range Dimensions & Mass Member Sections* Depth Width Mass D (mm) W (mm) (kg/m) 200x100x4.0 RHS RHS 200x100x6.0 RHS x150x5.0 RHS UB UB 200UB UB UB * sections supplied by others The Stramit Residential Floor Framing System has been designed to NASH Residential and Low-Rise Steel Framing manual - Part 1 (Design Criteria) to meet the performance requirement of the NCC. Use of these provisions reduces the uncomfortable bounce and vibration that may be present in other systems. The product range can be used for both single and two storey construction. Internal bearers or joists do not support any load bearing walls. Deflections under service loads are limited to a minimum of span/500 and 12mm. W L D 4

5 Durability Ground clearance requirements Stramit steel flooring is not intended for use in applications where the clearance above the ground is less than 400mm. A reduction of ground clearance is possible in small localised areas on sloping sites to a minimum of 150mm within 2m of a ventilated external wall. In all cases the subfloor ventilation details should meet the requirements of Part of the National Construction Code, Volume 2. For application requirements regarding location, product, finish, ventilation refer to table 3. Table 3 FLOOR SYSTEM DURABILITY CRITERIA One of the following applicable criteria must be adhered to ensure satisfactory performance of the floor system. The standard system is not suitable for applications closer than 300m to calm still coastal water or closer than 1km to rough active surf. Application >10km from the coast <10km but > 1km from the < 1km but > 300m from & not in a heavy coast & not in a heavy calm still coastal water & industrial area. industrial area. not in a heavy industrial area. Ground Floor Sub-floor can be Sub-floor should be enclosed Sub-floor must be enclosed completely open and incorporate ventilators, or & incorporate ventilators, or Sub-floor painted with etch primer Sub-floor painted with high plus water-based acrylic top coat. build epoxy mastic based system Upper Floor No ceiling lining required If fully enclosed building, If fully enclosed building, of Two Storey no ceiling lining required, or no ceiling lining required, or Building If not fully enclosed, sub-floor If not fully enclosed, sub-floor painted with etch primer plus painted with high build water based acrylic top coat epoxy mastic system Balcony / Provide weather tight Provide weather tight top cover Provide weather tight top Verandah top cover protection, or protection & complete cover protection & complete For open deck or strip encapsulation, or encapsulation, or flooring sub-floor painted Sub-floor painted with etch primer Sub-floor painted with high with etch primer plus water- plus water-based acrylic top coat build epoxy mastic system based acrylic top coat Notes: The information above is current at the time of publication. Please check the NCC and BlueScope website for the latest information and guidance. If uncertain about the use of the system in an aggressive environment, please contact your nearest Stramit office for advice. 5

6 DESIGN AND CONSTRUCTION Consideration of house plans is required when designing the floor system. The Stramit C-Joist system has the extended bearer option. Extended bearers provide design flexibility and allow for large spans to be achieved in areas such as above garages, rumpus, living rooms and balconies. Design Load Criteria The Limit State Method has been used throughout this brochure. Minimum design load and load combinations are generally as per NASH Standard Part 1. Load allowances Floor live load: 1.5 kpa 2.0 kpa - for balcony areas. Concentrated load: 1.8kN Dead load: Self-weight plus partition loads, plus weight of flooring, roof, and walls if applicable. Static and Dynamic serviceability Deflection, D 1 L/500 and D 1 < 12mm load combination: dead load + 100% live load. Deflection, D 2 < 2mm load :1kN. Assumptions Tile roof mass: 92kg/m 2. Metal roof mass: 40.7kg/m 2. Ceiling mass: 10.5kg/m 2. Wall mass: 29.5kg/m 2. Definitions balcony: an external area, one or more metres above ground. All load data has been based on using 18mm fibre cement sheeting as the flooring material; this provides substantial cross bracing whilst maintaining the 2.0kPa live loading requirement. partition loads: weight of non-load bearing walls, floor underlays and floor coverings, ceilings, services through floors, are assumed to be a maximum of 0.5kPa. joist spans: the distance between the end supports of a joist, which is usually the webs of the bearers to which the joist is attached. bearer spans: the centre distance between the piers or posts supporting the bearer. Single-span bearers only have two supports, one at each end, even if there are a series of such bearers in line. Continuous-span bearers have more than two equally-spaced supports. Design Limitations The Stramit C-Joist System is suitable for suspended floor framing in single occupancy buildings which come within the scope of a Class 1a dwelling as defined by NCC. The building should conform to all limitations as set out in Clause 1.2 of AS Floor live load exceeding 1.5kPa (2.0kPa for balconies) requires engineering calculations. Floor concentrated load of more than 1.8kN requires engineering calculations. May not be suitable for heavy items such as water beds, water tanks, large plants or aquariums, heavy gym equipment or pianos etc. Seek engineering advice for such applications. Not suitable for applications closer than 1km to aggressive environments. Connections between extended bearers and the structural elements of the building are the responsibility of the building designer. Stramit C-Joists must be used between bearers, as an in-plane system shown below. The information in this brochure is applicable only to the in-plane system. The use of the products in a joist on bearer configuration can lead to an undesirable transfer of movement-related vibration within and between rooms and is not recommended. Stramit C-Joist Stramit Bearers Stramit Extended Bearer Brackets Stramit C-Joists Extended Bearer Section (by others) Applied Standards AS/NZS 4600 Cold-formed steel structures. NASH Standard, Residential and Low-rise Steel Framing, Part 1 Design Criteria, The design tables include both single and continuous span configurations. 6

7 Load Areas ROOF-LOAD AREA Single or Upper Level of Two Storey Single span bearer - Tables 7 to 10 Continuous span bearer - Tables 11 & 12 roof-load area (tables 7-12) balcony & verandah area (tables 17-18) roof-load area (tables 13-16) non-roof-load area (tables 4-6) roof-load area (tables 13-16) OH roof-load area -single or upper level x Design Tables Data for the design of members can be found in Tables 4 to 18 and for connections and supports in Tables 19 to 24. Non-Roof-Load Areas These are defined as any floor areas within the internal confines of a residential building structure that supports 1.5 kpa live load, 0.5 kpa partition loading and are not supporting load-bearing walls or large concentrated loads (greater than 1.8kN). Internal areas can include bearers or joists at the sides of openings (eg. stairwell) OH ROOF-LOAD AREA Lower Level of Two Storey Single span bearer - Tables 13 & 14 Continuous span bearer - Tables 15 & 16 x NON-ROOF-LOAD AREA Any Floor level Single span bearer - Tables 4 & 5 Continuous span bearer - Table 6 roof-load area -lower level non-roof-load area Roof-Load Areas These are defined as areas that support combined roof, wall and floor loads within the residential building structure. They work as the combined load system of roof and floor areas. Balcony & Verandah Areas These are defined as floor areas that are external to the habitable building structure, and are located one or more metres above the ground. BALCONY AND VERANDAH NON-ROOF-LOAD AREA All Levels Single span bearer - Table 17 Continuous span bearer - Table 18 balcony & verandah area 7

8 NON-ROOF-LOAD AREA STRAMIT BEARERS - SINGLE SPAN Table 4 FLOOR SYSTEM - Non-Roof-Load Areas Maximum Joist Span 1.9mm thick SINGLE SPAN bearers bearer B11519 B18219 B23519 B28319 span J11510 J11512 J11515 J11519 J18210 J18212 J18215 J18219 J18224 J23512 J23515 J23519 J23524 J28319 J28324 <1.2* mm thick SINGLE SPAN bearers bearer B18224 B23524 B28324 span J18210 J18212 J18215 J18219 J18224 J23512 J23515 J23519 J23524 J28319 J28324 <1.4* Notes: only for joists at 450mm centres suitable for 19mm or 22mm thick particleboard floors not suitable for roof loading not suitable to support load bearing walls, or large concentrated load not suitable for balcony areas (*) for bearer of less than that span, or bearers sitting along the span on a bearing wall. extrapolation not permitted deflection L/500 and 12mm 8

9 Table 5 FLOOR SYSTEM - Non-Roof-Load Areas Maximum Joist Span SINGLE SPAN extended range bearers 200 UB 18 bearer span J11510 J11512 J11515 J11519 J18210 J18212 J18215 J18219 J18224 J23512 J23515 J23519 J23524 J28319 J UB 22 bearer span J11510 J11512 J11515 J11519 J18210 J18212 J18215 J18219 J18224 J23512 J23515 J23519 J23524 J28319 J UB 25 bearer span J11510 J11512 J11515 J11519 J18210 J18212 J18215 J18219 J18224 J23512 J23515 J23519 J23524 J28319 J bearer 310 UB 32 span J11510 J11512 J11515 J11519 J18210 J18212 J18215 J18219 J18224 J23512 J23515 J23519 J23524 J28319 J Notes: only for joists at 450mm centres suitable for 19mm or 22mm thick particleboard floors not suitable for roof loading not suitable to support load bearing walls, or large concentrated load not suitable for balcony areas extrapolation not permitted deflection L/500 and 12mm EXTENDED BEARERS - SINGLE SPAN NON-ROOF-LOAD AREA 9

10 NON-ROOF-LOAD AREA STRAMIT BEARERS - CONTINUOUS SPAN Table 6 FLOOR SYSTEM - Non-Roof-Load Areas Maximum Joist Span 1.9mm thick CONTINUOUS SPAN bearers bearer B11519 B18219 B23519 B28319 span J11510 J11512 J11515 J11519 J18210 J18212 J18215 J18219 J18224 J23512 J23515 J23519 J23524 J28319 J28324 <1.2* mm thick CONTINUOUS SPAN bearers bearer B18224 B23524 B28324 span J18210 J18212 J18215 J18219 J18224 J23512 J23515 J23519 J23524 J28319 J28324 <1.4* Notes: only for joists at 450mm centres suitable for 19mm or 22mm thick particleboard floors not suitable for roof loading not suitable to support load bearing walls, or large concentrated load not suitable for balcony areas (*) for bearer of less than that span, or bearers sitting along the span on a bearing wall. extrapolation not permitted deflection L/500 and 12mm 10

11 Table 7 Maximum Bearer Span, Single/Upper Storey Tiled Roof Single Span Bearers B11519 joist span nom B18219 joist span nom B18224 joist span nom Maximum Bearer Span, Single/Upper Storey Tiled Roof Single Span Bearers B23524 joist span nom B28319 joist span B28324 joist span nom STRAMIT BEARERS - SINGLE SPAN TILED ROOF B23519 joist span nom Notes: only for joists at 450mm centres with 19mm or 22mm thick particle board floors not suitable to support other load bearing walls, or large concentrated loads not suitable for balcony areas nom in table above refers to a floor load width less than 500mm linear interpolation is permitted extrapolation not permitted deflection L/500 and 12mm OH y = Roof Load Width = x 2 + OH joist span = y x ROOF-LOAD AREA - SINGLE / UPPER STOREY 11

12 ROOF-LOAD AREA - SINGLE / UPPER STOREY META L ROOF STRAMIT BEARERS - SINGLE SPAN Table 8 Maximum Bearer Span, Single/Upper Storey Metal Roof Single Span Bearers B11519 joist span nom B18219 joist span nom B18224 joist span nom B23519 joist span nom Notes: only for joists at 450mm centres with 19mm or 22mm thick particle board floors not suitable to support other load bearing walls, or large concentrated loads not suitable for balcony areas nom in table above refers to a floor load width less than 500mm linear interpolation is permitted extrapolation not permitted deflection L/500 and 12mm Maximum Bearer Span, Single/Upper Storey Metal Roof Single Span Bearers B23524 joist span nom B28319 joist span B28324 joist span OH y = Roof Load Width = x 2 + OH joist span = y x 12

13 Table 9 Maximum Bearer Span, Single/Upper Storey Tile Roof Single Span Bearers 200x100x4.0 RHS joist span x100x6.0 RHS joist span x150x5.0 RHS joist span Maximum Bearer Span, Single/Upper Storey Tile Roof Single Span Bearers 200UB22.3 joist span UB25.7 joist span UB32.0 joist span EXTENDED BEARERS - SINGLE SPAN TILED ROOF UB18.2 joist span Notes: only for joists at 450mm centres with 19mm or 22mm thick particle board floors not suitable to support other load bearing walls, or large concentrated loads not suitable for balcony areas nom in table above refers to a floor load width less than 500mm linear interpolation is permitted extrapolation not permitted deflection L/500 and 12mm = Roof Load Width = x 2 + OH joist span = y ROOF-LOAD AREA - SINGLE / UPPER STOREY 13

14 ROOF-LOAD AREA - SINGLE / UPPER STOREY META L ROOF EXTENDED BEARERS - SINGLE SPAN Table 10 Maximum Bearer Span, Single/Upper Storey Metal Roof Single Span Bearers 200x100x4.0 RHS joist span x100x6.0 RHS joist span x150x5.0 RHS joist span UB18.2 joist span Notes: only for joists at 450mm centres with 19mm or 22mm thick particle board floors not suitable to support other load bearing walls, or large concentrated loads not suitable for balcony areas nom in table above refers to a floor load width less than 500mm linear interpolation is permitted extrapolation not permitted deflection L/500 and 12mm Maximum Bearer Span, Single/Upper Storey Metal Roof Single Span Bearers = Roof Load Width = x 2 + OH joist span = y 200UB22.3 joist span UB25.7 joist span UB32.0 joist span

15 Table 11 Maximum Bearer Span, Single/Upper Storey Tile Roof Continuous Span Bearers B11519 joist span nom B18219 joist span nom B18224 joist span nom Maximum Bearer Span, Single/Upper Storey Tile Roof Continuous Span Bearers B23524 joist span nom B28319 joist span B28324 joist span STRAMIT BEARERS - CONTINUOUS SPAN TILED ROOF B23519 joist span nom Notes: only for joists at 450mm centres with 19mm or 22mm thick particle board floors not suitable to support other load bearing walls, or large concentrated loads not suitable for balcony areas nom in table above refers to a floor load width less than 500mm linear interpolation is permitted extrapolation not permitted deflection L/500 and 12mm = Roof Load Width = x 2 + OH joist span = y ROOF-LOAD AREA - SINGLE / UPPER STOREY 15

16 ROOF-LOAD AREA - SINGLE / UPPER STOREY META L ROOF STRAMIT BEARERS - CONTINUOUS SPAN Table 12 Maximum Bearer Span, Single/Upper Storey Metal Roof Continuous Span Bearers B11519 joist span nom B18219 joist span nom B18224 joist span nom B23519 joist span nom Notes: only for joists at 450mm centres with 19mm or 22mm thick particle board floors not suitable to support other load bearing walls, or large concentrated loads not suitable for balcony areas nom in table above refers to a floor load width less than 500mm linear interpolation is permitted extrapolation not permitted deflection L/500 and 12mm Maximum Bearer Span, Single/Upper Storey Metal Roof Continuous Span Bearers B23524 joist span nom B28319 joist span B28324 joist span OH y x = Roof Load Width = x 2 + OH joist span = y 16

17 Table 13 Maximum Bearer Span, Lower Level of 2 Storey Tile Roof Single Span Bearers 200x100x4.0 RHS upper level joist span + lower level joist span x100x6.0 RHS upper level joist span + lower level joist span x150x5.0 RHS upper level joist span + lower level joist span Maximum Bearer Span, Lower Level of 2 Storey Tile Roof Single Span Bearers 200UB22.3 upper level joist span + lower level joist span UB25.7 upper level joist span + lower level joist span UB32.0 upper level joist span + lower level joist span EXTENDED BEARERS - SINGLE SPAN TILED ROOF UB18.2 upper level joist span + lower level joist span Notes: only for joists at 450mm centres with 19mm or 22mm thick particle board floors not suitable to support other load bearing walls, or large concentrated loads not suitable for balcony areas nom in table above refers to a floor load width less than 500mm linear interpolation is permitted extrapolation not permitted deflection L/500 and 12mm OH y = Roof Load Width = x 2 + OH upper level joist span = x lower level joist span = y x ROOF-LOAD AREA - LOWER STOREY 17

18 ROOF-LOAD AREA -LOWER STOREY META L ROOF EXTENDED BEARERS - SINGLE SPAN Table 14 Maximum Bearer Span, Lower Level of 2 Storey Metal Roof Single Span Bearers 200x100x4.0 RHS upper level joist span + lower level joist span x100x6.0 RHS upper level joist span + lower level joist span x150x5.0 RHS upper level joist span + lower level joist span UB18.2 upper level joist span + lower level joist span Notes: only for joists at 450mm centres with 19mm or 22mm thick particle board floors not suitable to support other load bearing walls, or large concentrated loads not suitable for balcony areas nom in table above refers to a floor load width less than 500mm linear interpolation is permitted extrapolation not permitted deflection L/500 and 12mm Maximum Bearer Span, Lower Level of 2 Storey Metal Roof Single Span Bearers 200UB22.3 upper level joist span + lower level joist span UB25.7 upper level joist span + lower level joist span UB32.0 upper level joist span + lower level joist span OH y x = Roof Load Width = x 2 + OH upper level joist span = x lower level joist span = y 18

19 Table 15 Maximum Bearer Span, Lower Level of 2 Storey Tile Roof Continuous Span Bearers B11519 upper level joist span + lower level joist span nom B18219 upper level joist span + lower level joist span nom B18224 upper level joist span + lower level joist span nom Maximum Bearer Span, Lower Level of 2 Storey Tile Roof Continuous Span Bearers B23524 upper level joist span + lower level joist span nom B28319 upper level joist span + lower level joist span B28324 upper level joist span + lower level joist span STRAMIT BEARERS - CONTINUOUS SPAN TILED ROOF B23519 upper level joist span + lower level joist span nom Notes: only for joists at 450mm centres with 19mm or 22mm thick particle board floors not suitable to support other load bearing walls, or large concentrated loads not suitable for balcony areas nom in table above refers to a floor load width less than 500mm linear interpolation is permitted extrapolation not permitted deflection L/500 and 12mm OH y = Roof Load Width = x 2 + OH upper level joist span = x lower level joist span = y x ROOF-LOAD AREA - LOWER STOREY 19

20 ROOF-LOAD AREA -LOWER STOREY META L ROOF STRAMIT BEARERS - CONTINUOUS SPAN Table 16 Maximum Bearer Span, Lower Level of 2 Storey Metal Roof Continuous Span Bearers B11519 upper level joist span + lower level joist span nom B18219 upper level joist span + lower level joist span nom B18224 upper level joist span + lower level joist span nom B23519 upper level joist span + lower level joist span nom Notes: only for joists at 450mm centres with 19mm or 22mm thick particle board floors not suitable to support other load bearing walls, or large concentrated loads not suitable for balcony areas nom in table above refers to a floor load width less than 500mm linear interpolation is permitted extrapolation not permitted deflection L/500 and 12mm Maximum Bearer Span, Lower Level of 2 Storey Metal Roof Continuous Span Bearers B23524 upper level joist span + lower level joist span nom B28319 upper level joist span + lower level joist span nom B28324 upper level joist span + lower level joist span OH y = Roof Load Width = x 2 + OH upper level joist span = x lower level joist span = y x 20

21 Table 17 FLOOR SYSTEM - Non-Roof - BALCONY Loads Maximum Joist Span 1.9mm thick SINGLE SPAN bearers single bearer B11519 B18219 B23519 B28319 span J11510 J11512 J11515 J11519 J18210 J18212 J18215 J18219 J18224 J23512 J23515 J23519 J23524 J28319 J28324 <1.2* mm thick SINGLE SPAN bearers single bearer B18224 B23524 B28324 span J18210 J18212 J18215 J18219 J18224 J23512 J23515 J23519 J23524 J28319 J28324 <1.4* STRAMIT BEARERS - SINGLE SPAN Notes: only for joists at 450mm centres suitable for 15mm thick fibre-cement flooring. not suitable for roof loading not suitable to support load bearing walls, or large concentrated load (*) for bearer of less than that span, or bearers sitting along the span on a bearing wall. extrapolation not permitted deflection L/500 and 12mm BALCONY AREA 21

22 BALCONY AREA STRAMIT BEARERS - CONTINUOUS SPAN Table 18 FLOOR SYSTEM - Non-Roof- BALCONY Loads Maximum Joist Span 1.9mm thick CONTINOUS SPAN bearers bearer B11519 B18219 B23519 B28319 span J11510 J11512 J11515 J11519 J18210 J18212 J18215 J18219 J18224 J23512 J23515 J23519 J23524 J28319 J28324 <1.2* mm thick CONTINOUS SPAN bearers bearer B18224 B23524 B28324 span J18210 J18212 J18215 J18219 J18224 J23512 J23515 J23519 J23524 J28319 J28324 <1.4* Notes: only for joists at 450mm centres suitable for 15mm thick fibre-cement flooring. not suitable for roof loading not suitable to support load bearing walls, or large concentrated load (*) for bearer of less than that span, or bearers sitting along the span on a bearing wall. extrapolation not permitted deflection L/500 and 12mm 22