A Technical Guide for Floor & Roof Framing Construction

Transcription

1 A Technical Guide for Floor & Roof Framing Construction Nov 2006

2 The SIMPLE FRAMING SYSTEM TABLE OF CONTENTS The SIMPLE FRAMING SYSTEM Boise and the Building Regulations Boise and the Environment Features and Benefits Lifetime Guarantee Product Profiles Design Support: BC CALC, BC FRAMER BCI Joist Specifications BCI Joists Design Properties BCI Joists Used as Joists / Beams BCI Joists Used as Rim Joists / Bearers BCI Joists Used as Columns / Studs BCI Joists Used as Ties Allowable Nail Spacings BCI Joists Floor Applications About Floor Performance Floor Design Criteria Residential Floor Span Tables Floor Framing Details Overview Floor Details Framing Around Stair Openings Load Bearing External Cantilever Details Temporary Construction Bracing Hole Location and Sizing Ground Floor Construction Fire, Sound and Air Leakage Solutions BCI Joists Roof Applications Roof Design Criteria Roof Rafter Span Tables 400mm centres Roof Rafter Span Tables 600mm centres Roof Framing Details Overview Roof Details VERSA-LAM Products Introduction to VERSA-LAM Products VERSA-LAM Beam Specifications VERSA-LAM Design Properties VERSA-LAM Holes and Notches Allowable Nail Spacings VERSA-LAM Used as Beams Allowable Loads on VERSA-LAM Beams VERSA-LAM Used as Columns Common Framing Details Multiple Member Connectors VERSA-LAM Products Used as Rim Material Used as Rim Joists / Bearers Concentrated Load Capacities of Boise Rim Products BCI Joists Used as Wall Studs Metalwork Connectors Glossary Helpful Hints Contact Information Back Cover ABOUT BOISE The SIMPLE FRAMING SYSTEM is a comprehensive product and technical support package offering competitive floor and roof solutions for use in high performance domestic and commercial applications. Boise is headquartered in Boise, Idaho, and provides products and services to help customers work more efficiently, build more effectively, and create new ways to meet business challenges. We manufacture engineered wood products, plywood, lumber, and particleboard. Boise is a significant operator in the forest products industry worldwide. Visit us at our website at Globally, Boise is the fastest growing manufacturer of engineered wood products and is already the world s largest supplier of laminated veneered lumber (LVL) beams, lintels, columns, and posts. Boise has been supplying quality timber products to the UK and Europe since the opening of our UK office in Today, in partnership with Crown Timber plc, the country s leading provider of structural timber products to the timber engineering industry, we provide and support our SIMPLE FRAMING SYSTEM range of engineered wood products through a variety of specialist distribution facilities. Experienced and resourceful staff provide technical and distribution expertise dedicated to delivering complete and plot specific solutions nationwide. Our size and resource base ensures the stability of supply in an ever changing and evolving marketplace. Boise is a participant in the Sustainable Forestry Initiative (SFI ), a comprehensive forest management programme that is a combination of environmental responsibilities and sound business practices. The procurement systems of Boise s engineered wood product facilities have been audited by PricewaterhouseCoopers to the SFI Standard and its products will carry the SFI Label. These procurement systems provide tracking information on Boise s supply chain sources. The SIMPLE FRAMING SYSTEM is a highly efficient use of renewable timber fibre that can be tracked back to source. For more information on Boise corporate and our commitment to the environment, please visit Boise Engineered Wood Products Technical Guide Nov 2006

3 Boise and the Building Regulations BCI Joist Floors and Meeting the Requirements of the Building Regulations In the UK, all building products need to meet the requirements of the Building Regulations relevant to both the products and their intended use within a building. BCI Joists used in floor construction need to meet the requirements of Part A (structure), Part B (fire), Part E (sound) and Part L1 (air leakage). Boise s engineered wood products have been assessed by the leading UK building material approval authorities including the British Board of Agrement and TRADA. For BCI Joists these include BBA Certificate 99/3620 and TRADA Q Certificate Number 036/007. VERSA-LAM has been granted BBA Certificate 99/3619. Such certification is crucial for demonstrating the products compliance with Part A of the Building Regulations. Further information on the structural properties of these products are detailed on the following pages of this guide: Pages BCI Joists , 10, 11 & 51 VERSA-LAM , 45, 47, 48, 50 & 51 It is appropriate to consider the means of meeting the requirements of Parts B, E, and L1 of the Building Regulations simultaneously, to ensure that the floor solution meets all the requirements in an efficient and cost effective way. Details of the means by which BCI Joist floor construction meets these requirements are given on the following pages: Pages BCI Joists - Fire, Sound, and Air Leakage Sound testing for Part E requirements. Nov 2006 Technical Guide Boise Engineered Wood Products

4 Boise and the Environment Engineered wood products represent a bold step forward, not only in terms of their ease of use, excellent performance, and cost saving characteristics, but in the environmental credentials that they offer to specifiers and end users who are increasingly required to prove the eco ratings of the buildings that they construct. Unlike conventional timber, the performance of engineered wood products can be accurately predicted which means we can fine-tune a design so that exactly the right amount of product is employed for any given situation. Put simply, there is no need to over-specify, saving both money and resources. In addition, the product s manufacture requires no ancient or virgin timber and leads to very little wastage since virtually the whole tree is utilized typically at least a third less trees are required than to develop the same profile conventionally. It is also worth remembering that, due to the manufacturing process, engineered wood products are stronger than the solid wood alternative. When it comes to comparisons with steel and concrete, figures for embodied energy and manufacturing emissions leave engineered wood products as the clear environmental favourite every time. Properly managed, harvesting trees and protecting the environment are indeed compatible objectives. Quite rightly, the timber industry is under the environmental microscope, and it is ever more important for us all to prove that we are responsible through third-party auditing processes. At Boise, we are justifiably proud of our record. We are a founding member of the Sustainable Forestry Initiative (SFI ) programme and the company s fibre procurement systems are certified to the SFI standards while our engineered wood products qualify under the SFI s fibre source on-product labeling programme. In August 2005, the SFI scheme has introduced a chain of custody system that suppliers to UK government departments can use to identify the percentage content of timber from SFI managed forests and so assure buyers that the timber is from a sustainable source. The SFI scheme joins the Canadian Standards Association (CSA) Forest Stewardship Council (FSC) and The Programme for the Endorsement of Forest Certification (PEFC) schemes in providing assurance of both legal and sustainable timber. We have led the UK market since January 2005 by being the first company permitted to stamp our engineered wood products with the SFI label. This label means that the facility that produced the product bearing it is part of a programme whose participants plant more than 1.7 million trees every day. The SFI programme provides a standard for integrating the sustainable growing and harvesting of trees with protection of wildlife, plants, soil, and water quality. It is the only forest certification system with both land management and wood fibre procurement performance criteria and is founded on the concept of continuous improvement. There are currently over 150 million acres of forestland in North America enrolled in the SFI programme, making it among the world s largest sustainable forestry programmes. SFI is governed by a 15-member, multi-stakeholder Sustainable Forestry Board made up of five members from the forest industry, five representatives from the environmental community, and five other stakeholders from academia, small private landowners, and other interested groups. Boise undertakes SFI certification audits annually. Trained auditors from PricewaterhouseCoopers conduct the audits with a team of technical auditors specializing in hydrology, wildlife biology, roads, harvesting, and best management practices. During its most recent audit, PricewaterhouseCoopers cited a number of good sustainable management practices. For example, Boise s advance purchasing of wood chips, which allows chip vendors to plan volumes in advance, thus reducing the possibility of harvesting in unsuitable locations or during bad weather just to fulfill a contract. Also noted was the company s high level of professional leadership on numerous local, state, and national committees and organizations. Claims about the environmental performance of building materials and products are easy to make, but their sustainability is difficult to substantiate without a universal measuring system. We believe it is important to have a full understanding of how products compare so we are now pursuing the aim of profiling our products to help designers and specifiers ensure that they are selecting the materials that will best fulfill a sustainable brief. The more participants in the various certification programmes, the faster the building green movement will grow. Timber has always been an important building material but now, with the move towards environmentally conscious building gathering momentum, we must be ready with innovative timber products that shout their environmental credentials and remove any doubt from people s minds. EcoHomes EcoHomes is an assessment method in the UK that rates the environmental qualities of new and renovated dwellings. Buildings are verified by independent assessors and rated on a scale of pass, good, very good and excellent. The scheme rewards developers who improve the environmental performance of a development through good design, rather than through high capital cost solutions. EcoHomes is designed to help tackle climate change, resource use, impact on wildlife and balance these issues against the need to provide safe and healthy living and a high quality of life. For more details about EcoHomes please visit the website During 2005 Boise commissioned the BRE to carry out a life cycle analysis, environmental profile and EcoHomes points rating on our BCI Joist products. The results and subsequent Green Guide rating can be found on line at www. redbooklive.com in the section for domestic specification or we can supply details upon request. In summary, Boise has complied with the requirements identified in the scheme SD 028 and is authorised to use the BRE Certificate Mark on all publications related to the Environmental Profiles Scheme Certificate Number ENP 340 environmental profile of our BCI Joist products. Certificate number ENP 340, issue 1, 26/06/2006 to 25/06/2009 refers. Our undertaking to carry out this assessment in conjunction with the SFI Chain of Custody certification for both our BCI Joist and VERSA-LAM beam manufacturing facilities is testament to our commitment to the UK construction industry and the evolving specification market. For more information on Boise Engineered Wood Products, please telephone , boise.ewp.eu@bc.com or visit Boise Engineered Wood Products Technical Guide Nov 2006

5 The SIMPLE FRAMING SYSTEM 5 Feature Laminated Veneer Lumber (LVL) Tight manufacturing tolerances Wide range of products Clean appearance Stiff and strong Light in weight Eased edges Pre-stamped knock out holes High performance OSB web BC CALC and BC FRAMER Full layout drawings Precise component packages Installation guide Technical guide Technical support team Site trimming Materially efficient Quality assured BBA approved Lifetime guarantee Benefit Stable, strong and reliable engineered wood product that will not shrink, twist, cup, or bow like solid timber. Accurate product sizes for installation into service class 1 & 2 environments. No shrinkage - no squeaks. Competitive and compatible solutions. Inspires product confidence for the builder, inspector, and home buyer. Quiet, flat floors even ceilings. No herringbone strutting / blocking required at the mid span. Easy to handle. Reduces potential splinter injuries. Easy access for wiring and plumbing. Accommodates holes for larger services if necessary in accordance with guidelines detailed in this technical guide. Computer-aided design. Full supporting calculations and layout drawings. Easy-to-read, job-specific joist layout plans. Easy to install, no waste. Easy-to-read installation instructions. Comprehensive technical details. Expert help is on hand. Easy to cut on site using basic hand tools. Wise use of natural resources. The peeling process in the manufacture of LVL is a very efficient use of round log raw materials. The BCI Joist is a very efficient structural shape. Clean, consistent, reliable products. Instills confidence in the products and the construction. BCI Joists and VERSA- LAM Products are approved for use by the BBA. Lifetime Guaranteed Quality and Performance Boise warrants its BCI Joist, VERSA-LAM, and ALLJOIST products to comply with our specifications, to be free from defects in material and workmanship, and to meet or exceed our performance specifications for the normal and expected life of the structure when correctly stored, installed and used according to our Installation Guide. Engineered Wood Products Certificate Number 036/007 Nov 006 Technical Guide Boise Engineered Wood Products

6 6 The SIMPLE FRAMING SYSTEM BCI Joists A world leader in high quality engineered wood products, Boise Engineered Wood Products offers a wide range of BCI Joists. BCI Joists are manufactured to precise specifications using VERSA-LAM laminated veneer lumber flanges bonded to an orientated strand board (OSB) web. The use of VERSA-LAM as the flange material avoids the inherent problems that plague solid timber such as shrinking, twisting, cupping, and bowing, all of which contribute to squeaking floors. Light in weight, yet immensely strong, the long-length BCI Joists are quick and easy to install. Delivered to site in precise precut component packages, the SIMPLE FRAMING SYSTEM dramatically reduces installation times and the potential for error. Straight and true, BCI Joists create flat floors and even ceilings. Pre-stamped holes in the OSB web allows speedy installation of wiring and plumbing. Other holes can be made in the web to accommodate larger services. VERSA-LAM VERSA-LAM provides the foundation for the SIMPLE FRAMING SYSTEM. Manufactured by bonding high-specification rotarypeeled timber veneers to create huge billets of engineered wood, VERSA-LAM is one of the strongest and most reliable engineered wood products available in the UK today. Available in a wide range of sizes, VERSA-LAM is an excellent partner for BCI Joists in the SIMPLE FRAMING SYSTEM and can also be used for a variety of purposes including floor and roof beams, lintels, purlins, columns, studs, door stock, and more. VERSA-LAM is popular amongst timber frame designers and manufacturers with a range of sizes suitable for timber frame as well as masonry construction. Boise leads the world in new veneer technology. Our Product Development Team continuously researches new veneer species and bonding techniques to further push the boundaries of engineered wood products. Boise Engineered Wood Products Technical Guide Nov 2006

7 The SIMPLE FRAMING SYSTEM 7 VERSA-LAM as Rim VERSA-LAM is available in a 38mm width for use as a high grade rim board in timber frame applications. It can also be used as a stairwell closue and in certain beam applications. VERSA-LAM has been specially developed to withstand high compressive stresses perpendicular to the grain. This makes it ideal as a rimboard in timber frame construction ot transmit the vertical loads from load-bearing walls through the floor construction to the load-bearing walls below. The use of VERSA-LAM can reduce the need for squash blocks in high load applications. VERSA-LAM is available in a range of depths to suit the other components in the SIMPLE FRAMING SYSTEM. I-bloc UK Patent GB B I-bloc is a specially profiled LVL joist cap designed to enable BCI Joists to be built into masonry external and party walls whilst meeting all current Building Regulation and NHBC technical requirements. There is no need for extensive propping as the I-bloc allows decked floors to be used as a safe working platform. There is also no need for additional restraint straps parallel to the joists as they sit on the wall with a minimum 90mm bearing. Using the I-bloc stops air leakage around the joist ends in compliance with Building Regulations, Part L1 (air leakage). Once installed, it eliminates the need for a silicone sealant finish at the joist ends on the inner blockwork leaf, subject to good workmanship when keying with mortar. The I-bloc is quick and easy to use; it is simply a push fit with no mechanical fixings or glue required. It can be used on perimeter and party walls in compliance with Building Regulations, Part B (fire) and Part E (sound) requirements. Nov 2006 Technical Guide Boise Engineered Wood Products

8 8 Design Support BC CALC Software BC CALC is our software program for sizing BCI Joists and VERSA-LAM beams and operates within Microsoft Windows 95, 98, NT, 2000, ME and XP. BC CALC is simple to use, yet flexible enough to analyze a wide variety of joist and beam applications. Span, load and hole information entered by the user is used by the program to analyze the SIMPLE FRAMING SYSTEM range of engineered wood products. Easy to read design reports may be printed after analysis has been run. This report clearly shows all span and load information as well as the analysis results. BC CALC is available to designers, architects and engineers on CD-ROM. For more information, call Boise Engineered Wood Products on BC FRAMER Software Floor and roof framing layouts are quickly and expertly created by our skilled designers using our powerful and flexible BC FRAMER software package. Working in conjunction with BC CALC, the software allows prompt detailing of walls, framing areas, stairwell openings and joist layouts creating cost effective design solutions. 3D views, large scale details, full product and price schedules are all at our designers fingertips. BC FRAMER software provides full working drawings for design approval and for site installation. The software can also interface with other CAD systems to ensure full compatibility and flexibility for the Building Designer. Boise Engineered Wood Products Technical Guide Nov 2006

9 2006 European BCI Product Joists Profiles 9 BCI 5000s 28mm 9.5mm 241mm 302mm 356mm BCI 6000s 28mm 9.5mm 241mm 302mm 356mm 406mm BCI 6500s BCI 60s BCI 90s 28mm 9.5mm 241mm 302mm 356mm 406mm 38mm 9.5mm 241mm 302mm 356mm 406mm 38mm 9.5mm 241mm 302mm 356mm 406mm 51mm 59mm 65mm 59mm 89mm BCI Joist Specifications Materials and Manufacture BCI Joists are manufactured with VERSA-LAM LVL flanges, oriented strand board (OSB) webs and waterproof structural adhesives. The OSB web sections are glued together at 1220mm centres to form a continuous web. The webs are glued into a 12mm deep groove in the centre of the wide face of the flange members. All components are machineassembled and pressed in one continuous operation. Boise operates the two largest and fastest I-joist plants in the world. Quality Assurance BCI Joists are approved for use in the UK by the British Board of Agrément and are manufactured under a factory production control system audited on a monthly basis by a third-party inspection agency. Sizes Five joist series, BCI 5000s, 6000s, 6500s, 60s and 90s, are available. Each joist is available in a range of depths as detailed in the product profile illustration above. Joists are manufactured up to 20m long. Tolerances The tolerances (in mm) on member sizes are: Joist length... ±3.2 Joist height... ±0.76 Flange thickness... ±1.27 Flange width to Moisture Content BCI Joists will arrive on-site with a moisture content of 8% to 10%. In a service class 1 environment (as defined in BS5268 2:2002), BCI Joists will remain at an equilibrium moisture content of approximately 10%, whilst in a service class 2 environment, they will absorb a little moisture from the atmosphere and attain a final equilibrium moisture content of 12% to 14%. NOTE: The corresponding equilibrium moisture contents of solid timber in service classes 1 and 2 will be approximately 12% and 18%, respectively, having typically been delivered to site at a moisture content of 18% to 24%. Preservative Treatment BCI Joists are untreated products with a natural durability sufficient to ensure a minimum design life of 60 years when installed in a service class 1 or 2 environment and not subject to mechanical damage or insect attack. Differences in the swelling characteristics of the materials used in BCI Joists mean that preservative treatment should not be undertaken without consulting Boise Engineered Wood Products s as this may affect the structural integrity of the component. BCI Joists are approved for use under the UK Building Regulations by British Board of Agrément BBA Certificate No. 99/3620. BBA certification is recognised by: N.H.B.C. Zurich Municipal UKTFA TRA Building Contractors Building Control Officers Engineered Wood Products Certificate Number 036/007 Nov 2006 Technical Guide Boise Engineered Wood Products

10 10 BCI Joists are intended for use as structural members such as floor or roof joists, beams, rafters, wall studs or ceiling ties, in service class 1 or 2 environments as defined in BS5268 2:2002. Design properties for BCI Joists in these internal conditions are given in the table below for long-term loading. Design properties for shorter load durations may be determined by applying the appropriate value of the k 3 modification factor given in BS5268 2:2002. BCI Joists Used as Joists / Beams Long-Term Design Properties of BCI /1, /2 Joists in Bending (k 3 = 1.0) Service Class 1 Conditions (20 o C / 65% rh) Joist Depth Service Class Joist Type 5000s 6000s 6500s 60s 90s 5000s 6000s 6500s 60s 90s 5000s 6000s 6500s 60s 90s 6000s 6500s 60s 90s Long-Term Design Properties of BCI /1, /2 Joists in Bending (k 3 = 1.0) Service Class 2 Conditions (20 o C / 85% rh) Joist Depth Service Class Joist Depth Joist Type 5000s 6000s 6500s 60s 90s 5000s 6000s 6500s 60s 90s 5000s 6000s 6500s 60s 90s 6000s 6500s 60s 90s Joist Weight (kg/m) 5000s 6000s 6500s 60s 90s BCI Joists Design Properties Bending Shear End Reaction (kn) Intermediate Reaction (kn) Moment Resistance 45mm Bearing 89mm Bearing 89mm Bearing 133mm Bearing Capacity (knm) Flexural (kn) Rigidity Shear Web Stiffeners Web Stiffeners Web Stiffeners Web Stiffeners (El) Rigidity Load Non- (Nmm 2 x (GA) Sharing Load Load Non- No Yes No Yes No Yes No Yes No Yes No Yes No Yes No Yes Sharing 10 9 ) Sharing Load Sharing (Nx10 6 ) Load Sharing Non-Load Sharing Load Sharing Non-Load Sharing Load Sharing Non-Load Sharing Load Sharing Non-Load Sharing Bending Shear End Reaction (kn) Intermediate Reaction (kn) Moment Flexural Resistance 45mm Bearing 89mm Bearing 89mm Bearing 133mm Bearing Capacity (knm) Rigidity (kn) (El) Shear Web Stiffeners Web Stiffeners Web Stiffeners Web Stiffeners (Nmm 2 x Rigidity Load Non ) (GA) Sharing Load Load Non- No Yes No Yes No Yes No Yes No Yes No Yes No Yes No Yes Sharing Sharing Load Sharing (Nx10 6 ) Load Sharing Non-Load Sharing Load Sharing Non-Load Sharing Load Sharing Non-Load Sharing Load Sharing Non-Load Sharing Notes /1 The properties given above are applicable to long-term load duration. Permissible strength values for other load durations may be obtained by multiplying by 1.25 for medium-term loading or 1.5 for short-term loading as detailed in BS5268-2:2002. /2 The properties given above presuppose adequate lateral restraint is provided to the compression flange via continuous boarding or discrete restraints applied at maximum centres of 400mm. /3 For web stiffener specifications and fixing details, see page 18. /4 The maximum deflection of a uniformly loaded joist can be calculated from the following equation : d = (5wL 4 /384EI) + (wl 2 /8GA) where : w is the uniform load (kn/m) L is the span (m) EI is the flexural rigidity obtained from the table GA is the shear rigidity obtained from the table Boise Engineered Wood Products Technical Guide Nov 2006

11 BCI Joists Design Properties 11 BCI Joists Used as Rim Joists / Bearers Maximum Long-Term Load on BCI Joists Subject to Uniform Compression Perpendicular to the Joist Direction (Service Classes 1 and 2) Joist Depth Maximum Load per Metre Run (kn/m) BCI Joists Used as Columns / Studs The maximum axial compression capacity of BCI Joists used as struts should be based upon the capacity of the flange cross-section only: BCI Joists Used as Ties P c = σ c,adm x A f x k 12 x k 3 Where: P c = maximum axial compression load (N) σ c,adm = 19.5 N/mm 2 for Service Class 1 = 17.5 N/mm 2 for Service Class 2 A f = Total cross-sectional area of the flanges (mm 2 ) 12 k = Slenderness modification factor from BS5268 2: k = Load duration modification factor from BS5268 2:2002 The maximum axial tensile capacity of BCI Joists used as struts, where both flanges are equally loaded, should be based upon the capacity of the flange cross-section only: Allowable Nail Spacings P t = σ t,adm x A f x k 3 x (2440 ) L Where: P t = maximum axial tension load (N) σ t,adm = 15.0 N/mm 2 for Service Class 1 = 13.5 N/mm 2 for Service Class 2 A f = Total cross-sectional area of the flanges (mm 2 ) 3 k = Load duration modification factor from BS5268 2:2002 L = Member length (mm) [min. value = 2440 mm] Nailed joints in VERSA-LAM flanges of BCI Joists should be designed using the permissible nail values given in BS : 2002 for C27 timber. Nails should be spaced in accordance with the following table: Nailing in Wide Face (Perpendicular to Glue Lines) Nail Diameter End Distance Edge Distance Along Face - Across Face - (mm) (mm) (mm) Parallel to Grain (mm) Perpendicular to Grain (mm) Nailing perpendicular to Glue Lines (Wide Face) Nailing in Narrow Face (Parallel to Glue Lines) Nail Diameter End Distance Edge Distance Along Face - Across Face - (mm) (mm) (mm) Parallel to Grain (mm) Perpendicular to Grain (mm) Nov 2006 Technical Guide Boise Engineered Wood Products Nailing parallel to Glue Lines (Narrow Face)

12 12 BCI Joists Floor Applications About Floor Performance Increasing the stiffness of a floor system will improve its performance and feel. The most efficient way of increasing the stiffness of the floor is to deepen the joists this is simple engineering fact - a 25% increase in joist depth will have the same effect as doubling the joist width or halving the joist centres. A clear justification for the deeper is cheaper statement that echoes around the engineered wood product industry. Our designers can easily design the floor to performance levels above the minimum code requirements if so desired. The performance of a floor is matter of opinion. The feel that satisfies one individual may not satisfy another. Many factors affect the perceived performance of a floor. These include: The depth of the joist The stiffness of a floor can be markedly improved by increasing joist depth. For example, a 25% increase in joist depth will double the floor stiffness. The spacing of the joist system The stiffness of a floor increases in proportion to reductions in joist spacing. Continuous or simple spans Allowing joists to span over internal load-bearing walls instead of breaking them at these points can increase floor stiffness by up to 240%. The decking / flooring material Thicker decking slightly improves floor performance 22mm chipboard increases floor stiffness by 2%* compared to 18mm chipboard and means less 'local' deflection under foot. The fixing of the decking material to the joist Gluing the floor deck to the joists significantly improves floor stiffness, by as much as 70%.* The ceiling material below the joist Directly applied ceiling boards can improve floor performance by up to 3%.* Level bearings Unlevel bearings can mean joists feel "spongy" under foot near bearing positions. The location of walls and furniture The position and size of dead loads on floors can either dampen or exaggerate the dynamic response of floors under foot. *Figures established from independent laboratory research carried out on behalf of the UK Government. Boise Engineered Wood Products Technical Guide Nov 2006

13 BCI Joists Floor Applications 13 Floor Design Criteria BCI Joists are designed for floor applications using the principles of BS5268 2:2002 and the joist properties contained in BBA Certificate 99/3620. In general, it can be assumed that floors in modern centrally heated buildings will achieve a Service Class 1 moisture condition. Uniformly distributed dead and imposed loads will be assumed across the whole floor unless otherwise directed. Imposed loads will be selected from the examples tabulated below depending on the intended use of the floor. Dead loads can be taken from the schedule of material weights tabulated below. Schedule of Material Dead Weights Floor Decking kn/m 2 Ceiling Finishes kn/m 2 18mm Chipboard mm Plaster Skim mm Chipboard mm T&G Boarding mm Plasterboard mm T&G Boarding 15mm OSB mm Plasterboard 12.5mm Firecheck P/board mm OSB 15mm Plywood Partition Loads kn/m 2 19mm Plywood mm Plasterboard on 18mm Particleboard / timber studwork mm Particleboard /1 16mm S.W. Boarding Insulation kn/m 2 19mm S.W. Boarding 12.5mm Sound Resistant P/board Rock Wool (25mm) Glass Fibre (50mm) mm Gypsum Plank 0.14 /1 Particleboard refers to cement bonded particleboard Type T1 Flooring. Standard Imposed Load Allowances Intended Room Usage kn/m 2 Domestic Floors Office Floors Computer Rooms Storage Rooms Gymnasium Stationery Stores Balconies Billiard Rooms Areas with Fixed Seating Concert Halls Bedrooms in Hotels/Motels Dining Rooms/ Lounges Cafes /1 Taken from BS6399:Part1: /m height of storage /m height of storage Same as rooms to which they give access (min 1.5 for domestic use, 4.0 for public / office use) BS6399:Part 1 recommends that the loads for all permanent partitions are applied in the given locations as dead loads. In practice, a standard dead load of 0.75kN/m 2 is generally assumed which makes allowance for a standard floor construction (22mm chipboard decking + 15mm plasterboard ceiling), supporting internal non loadbearing partitions above. Exceptionally, this may be reduced to 0.5kN/m 2 where no partition walls are known to exist, or increased to a higher value where a heavier form of construction is used. The minimum stiffness permitted for floors in BS5268 2:2002 is defined by the deflection being limited to 0.3% of the span or 14mm, whichever is the lesser. Boise recommends that BCI Joists are designed to higher stiffness criteria in order to provide superior floor performance. NHBC technical standards require that the maximum deflection is limited to 12mm. Floor performance can be enhanced consistently in practice if the decking is glued to the joist platform, as highlighted by the factors affecting floor performance. This step is also recommended as a basis for ensuring superior floor performance in practice. Timber Stud Partition Chipboard Flooring VERSA-LAM R BCI Joist Nov 2006 Technical Guide Boise Engineered Wood Products Plasterboard

14 BCI Joists Floor Applications The table below represents maximum spans for a range of floor performance levels for joists in a single span application. Multispanning a joist over intermediate supports can result in improved Residential Floor Span Tables performance or the ability to span further. Please refer to BC CALC or Boise Engineered Wood Products engineering department for further details. Single Span Double Span Max. span Max. span Max. span /1, /2 Maximum spans (m) for domestic construction Joist Depth (mm) BCI Joist Type Single Span Code Recommended /4 NHBC Recommended /5 100% Stiffer than Code /6 600c/c 480c/c 400c/c 300c/c 600c/c 480c/c 400c/c 300c/c 600c/c 480c/c 400c/c 300c/c 5000s Single Span s Single Span mm 6500s Single Span BCI 40s 60s BCI 45s Single Span BCI 60s s Single Span s Single Span s Single Span mm 6500s Single Span BCI 40s 60s BCI 45s Single Span BCI 60s s Single Span s Single Span s Single Span mm 6500s Single Span BCI 40s 60s BCI 45s Single Span BCI 60s s Single Span s Single Span mm 6500s 60s Single Span Single Span BCI 40s 90s BCI 45s BCI 60s Single Span Notes : /1 All spans quoted are engineered spans measured between centres of bearing points. Minimum bearing lengths required are 45mm at joist ends and 89mm at intermediate supports. /2 All spans quoted are for standard domestic loading (including allowance for internal partitions) 0.75kN/m dead loading:.5kn/m imposed loading. /3 Spans quoted for double span joists are maximum achievable values assuming both spans are equal. Where joists are continuous over two unequal spans, smaller values will apply, intermediate between the single and double-span values quoted, depending upon the relative proportions of the spans involved. /4 Minimum floor stiffness recommended in BS5268-2:2002 dictated by maximum allowable floor deflection = 0.% of the span up to a maximum of mm. /5 Minimum floor stiffness recommended by NHBC dictated by maximum floor deflection = 0.% of the span up to a maximum of mm. /6 100% higher floor stiffness than recommended in BS5268-2:2002 dictated by maximum floor deflection = 0.5% of the span up to a maximum of 7mm. /7 These spans are stress controlled. All other spans are deflection controlled. Boise Engineered Wood Products Technical Guide Nov 006

15 Floor Framing Details 15 For mutiple member connectors details, see F10 to F13. For stairwell framing details, see pages 25 and 26. For timber frame rim details, see F1 to F5. For masonry rim details, see F16 to F19 and F21. For hole location and sizing chart, see page 28. For masonry wall restraint details, see F18. For cantilever details, see F14. For stud wall support details, see F3a and F7 to F9. For fixings to steel beams, see F15. Solid blocking or herring-bone strutting is NOT required on the SIMPLE FRAMING SYSTEM. For installation stability, see Temporary Construction Bracing details on page 27. Nov 2006 Technical Guide Boise Engineered Wood Products

16 16 BCI Joists - Floor Applications F1 Fixing at end bearing. F1a Party wall end bearing. VERSA-LAM. BCI Joist. 1-No 3.35x65mm locator nail. 45mm VERSA-LAM. 38mm VERSA-LAM Rim. For alternative detail, see F4a End blocking on both sides of BCI Joist. 1-No 3.35x65mm locator nail. 45mm minimum bearing length. Note: To avoid splitting flange, start locator nail at least 38mm from end. Nails will need to be driven at an angle to prevent splitting of bearing plate. BCI Joist. 45mm minimum bearing length. Note: To avoid splitting flange, start locator nail at least 38mm from end. Nails will need to be driven at an angle to prevent splitting of bearing plate. F2 BCI Rim blocking. F3a Non load-bearing stud wall (perpendicular to joist). Note: Nail BCI rim blocking to wallplate using 3.35x65mm nails each side at 300mm centres. Skew nail top of blocking to joist. Perpendicular non load-bearing stud wall. BCI rim blocking. Sole plate to be fixed to BCI Joist. F4 VERSA-LAM Rim (perpendicular to joist - external wall). Note: Nail VERSA-LAM rim board to BCI Joists with 2-No 3.35x65mm nails, one at the top and one at the bottom (see detail F1). F4a BCI blocking. VERSA-LAM Rim (perpendicular to joist - party wall). 38mm C16 timber block fitted between webs of BCI Joist. BCI Joist. 38mm VERSA-LAM. 45mm minimum bearing length for BCI Joist. Note: Skew nail VERSA-LAM rim board to wallplate using 3.35x65mm nails at mid point between joist spacings. 89mm stud. Boise Engineered Wood Products Technical Guide Nov 2006

17 F5 BCI Joists - Floor Applications VERSA-LAM Rim (parallel to joist - external wall). F5a 17 VERSA-LAM Rim (parallel to joist - party wall). W W BCI Joist of adequate width to support floor decking and plasterboard. W 2 W 2 VERSA-LAM of adequate width to support floor decking and plasterboard. W 2 W 2 Skew nail VERSA-LAM rim board to plate using 3.35x65mm nails at 300mm centres. Skew nail VERSA-LAM rim board to plate using 3.35x65mm nails at 300mm centres. F6 Joist spliced on load-bearing wall. F7 Non load-bearing stud wall (parallel to joist). BCI Joist blocking required where walls are not built up to underside of floor deck. Sole plate to be fixed to nogging. Non load-bearing partition wall. Min. 5mm gap at top. 15x300mm OSB or plywood splice block to one side only. Fix using 6-No 3.35x65mm nails, clenched. Floor deck. 35x72mm noggings at 600mm centres with Z-clips at both ends. Attach with 4-No 3.75x30mm square twist nails. F8 Wall to wall load transfer (BCI Joist blocking). F8a Wall to wall load transfer (squash blocks). Use 45mm VERSA-LAM blocking in areas where 3 or more multiple studs are used. Load-bearing internal wall perpendicular to joist direction and aligned with wall below. Load-bearing wall above (aligned over wall below). Use BCI Joist blocking where less than 3 multiple studs are used. 2mm 89mm min. BCI Joist blocking. Note: Nail blocking to wallplate using 3.35x65mm min. nails at 300mm centres. Squash blocks (38x89mm min.) Nov 2006 Technical Guide Boise Engineered Wood Products

18 18 BCI Joists - Floor Applications F9 Concentrated load transfer (squash blocks). F11 Backer block (face mount hanger). High vertical load. Note: Fix backer block using 8-No 3.35x65mm nails clenched (see F11b). Use 100mm nails for 90s series joist. Face mount joist hanger. Provide squash blocks where vertical load exceeds rim capacity (see page 51 of the technical guide). Backer block required on both sides of web. F10 Web stiffeners (fixing and specification). Web stiffeners may be used to increase allowable reaction values in the applications below. Small gap: 3mm min. 50mm max. 60mm min. 60mm min. Joist Depth Fixings Tight Fit. Intermediate Bearings. Tight Fit. End Bearings. 50mm min. 50mm min No 3.35x65mm No 3.35x65mm No 3.35x65mm No 3.35x65mm Note: Use 100mm nails for 90s Series Joists. All Nails to be 3.35 x 65mm driven through and clenched over on far side. = = = 241mm 2 nails. 60mm min. = = = = 302mm 25mm min. 3 nails. 60mm min. Tight Fit. Tight Fit. Partial Depth Hangers (not restraining top flange). Concentrated Loads. OSB or Plywood web stiffener: 5000s Series 18x60mm min. 6000s Series 22x60mm min. 6500s Series 25x60mm min. 60s Series 22x60mm min. 90s Series 38x60mm min. Note: Web stiffeners are not required for BCI Joists unless used in hangers that do not extend up to restrain the top flange of the BCI Joist or as required by design. = = = = 356mm 25mm min. 5 nails. = = = = 406mm 25mm min. 6 nails. F11a Backer block (top hung hanger). F11b Backer block (fixing and specification). Note: Fix backer block using 8-No 3.35x65mm nails clenched (see F11b). Use 100mm nails for 90s series joist. Top flange joist hanger. Tight fit. With top flange hangers, backer block must be installed tight to the underside of top flange. Backer block required on both sides of web. 3.35x65mm nails clenched (100mm nails for 90s Series Joists). Series 5000s 6000s 6500s 60s 90s Backer Block Thickness 20mm wood panel 25mm wood panel 27mm wood panel 25mm wood panels 18mm + 22mm wood panels = = 300 Where nails are clenched, all nails can be driven from near side. Depth 241mm 302mm 356mm 406mm Backer Block Depths 147mm 219mm 269mm 319mm Boise Engineered Wood Products Technical Guide Nov 2006

19 F11c BCI Joists - Floor Applications No backer block required (Cullen UI or HUI hanger). F11d 19 No backer block required (Simpson Strong-Tie ITB hanger). UI or HI Hanger fixed using 3.75x30mm square twist nails through all holes. ITB Hanger fixed using a minimum of 12-No 3.75x30mm square twist nails into flanges of supporting joist. Backer blocks are not required when UI or HI hangers are used. Backer Blocks are not required when ITB hangers are used. UI hanger has only top chord return flange. HI hanger has full depth return flange. F12 Filler block (fixing and specification). F12a 2-ply BCI filler block. Gap required to avoid forced fit. = = Fix 2-ply BCI Joists together using filler blocks at all bearing points, at incoming load positions, and at max 3.6m centres (see F12b). = = 3.35x65mm nails clenched Series 5000s 6000s 6500s 60s 90s Filler Block Thickness 40mm Timber 47mm Timber 53mm Timber 47mm Timber 75mm Timber Depth 241mm 302mm 356mm 406mm Filler Block Depth 147mm 97mm + 122mm 122mm + 147mm 147mm + 172mm See F12 for fixing details. F12b Filler block (short length option). F12c Filler block (full length option). Note: Maximum spacing between filler blocks to be 3.6 metres. Intermediate filler blocks should be installed between bearing and incoming load positions. 3.6m maximum. Note: A continuous filler and backer block should be considered where numerous incoming joists occur. Continuous (See F11b and F12 for fixing details.) backer block. 3.6m maximum. Filler block. Intermediate filler block installed where required. Filler block (see F12 for fixing details). Nov 2006 Technical Guide Boise Engineered Wood Products

20 20 BCI Joists - Floor Applications F12d 2-ply BCI (Cullen I-clip). F12e Cullen I-Clip (Localized connection). I-Clips fully nailed using 3.75mm square twist nails. 2-No I-Clips fixed each side of joist where incoming load is greater than 7.6kN. Note: I-Clips to be installed in accordance with manufacturer s instructions. 200mm. 2.0m max. 2.0m max. 200mm. Intermediate I-Clip installed where required. Fix 2-ply BCI Joists together using I-Clips located within 200mm of all bearing points and incoming load positions and at max 2.0m centres (see F12e). 1-No I-Clip fixed each side of joist where incoming load is 7.6kN or less. F12f Cullen I-Clip (Multiple connection). F13 BCI Joist to VERSA-LAM connection. 2-No I-Clips fixed between joists where incoming point loads are greater than 3.8kN. Face fixed or top flange hanger. 1-No I-Clip fixed between joists where incoming point loads are 3.8kN or less (see F12d). VERSA-LAM beam. Note: Web stiffeners are required where sides of hanger do not extend up to give restraint to the top flange (see F10). F14 Typical standard cantilever. F14a Typical cantilever with wall support. Closure. BCI Joist blocking required for all cantilever conditions. Structural panel closure. Web stiffener may be required on each side of joists. BCI Joist blocking required for cantilever. Max. 1/3rd back span. Fix using 3.35x65mm nails at 300mm centres. Structural panel reinforcement. 600mm 600mm Backer block. Boise Engineered Wood Products Technical Guide Nov 2006