Timber joist ceilings and separating / compartment floors Timber joist ceilings and separating / compartment floors

Transcription

1 Timber joist ceilings and separating / compartment floors Pendrill Park, Papworth Everard Countryside Properties 6

2 Timber joist ceilings and separating / compartment floors providing a means of direct and indirect fixing of plasterboards to timber joists Ceilings to timber joist floors are an established form of ceiling construction, widely used in both new housing and refurbishment. Separating / compartment floors are often specified as fire and sound resisting floors in residential units such as flats and apartments to meet the requirements of national Building Regulations. Key facts 0 -db 66 Airborne - - db Impact mins Sector Office / commercial Educational Residential Healthcare Leisure Industrial Gyproc Drywall Timber Screw - direct fix Gypframe RB Resilient Bar / Gypframe RB SureFix Bar - indirect fix Traditional and established method Versatile Use of Gyproc Drywall Timber Screws minimises fixing defects Gypframe RB Resilient Bar and Gypframe RB SureFix Bar provide enhanced acoustic performance and eliminate nail popping Can achieve high performance levels Quick and easy to install 7

3 System components Gypframe metal products RB Resilient Bar Length 000mm RB SureFix Bar Length 000mm Gyproc and Glasroc board products Gyproc WallBoard Thickness., mm Width 900, 00mm Gyproc FireLine Thickness., mm Width 900, 00mm Gyproc SoundBloc Thickness., mm Width 00mm Gyproc Plank Thickness 9mm Width 600mm Gyproc HandiBoard Thickness 9.,.mm Width 600, 900mm Glasroc MultiBoard Thickness 6, 0,.mm Width 00mm Glasroc FireCase S Thickness mm Width 600, 00mm Also available in DUPLEX grades where vapour control is required. Also available in MR version (moisture resistant). Fixing and finishing products Gyproc Drywall Timber Screws or Glasroc FireCase Screws For a positive direct fix of boards to timber joists. Gyproc Nails For traditional direct fixing of boards to timber joists. Gyproc Drywall Screws For fixing boards to Gypframe Resilient Bars, and Gypframe Resilient Bars to timber joists. Gyproc Sealant For sealing airpaths to achieve optimum sound insulation. Gyproc jointing materials For seamless jointing. Thistle Board Finish or Thistle Multi-Finish To provide a plaster skim finish. Isowool APR 00 mm, 0mm and 00mm for improved acoustic performance. Isowool General Purpose Roll For improved acoustic performance. Sound Deadening Floor Slab - Rigid Grade For improved impact sound insulation. Stone mineral wool For providing acoustic / thermal insulation. 8

4 T F E bgtechnical.enquiries@bpb.com Installation overview - Gypframe RB SureFix Bar illustrated Direct fix plasterboard ceiling Boards are fixed to ceilings, prior to lining walls and partitions, with the long edges at right angles to the joists. Cut-ends are located over a joist or timber nogging support. Timber noggings (where required) are fitted between joists at room perimeters to support board edges. Noggings may also be required to support board edges in the field of the boards. Boards are preferably fixed to timber supports using Gyproc Drywall Timber Screws, to minimise fixing defects. Indirect fix to Gypframe RB SureFix Bars The bars are fixed through the single fixing flange to the underside of timber joists (at 90 to them) using Gyproc Drywall Screws. The first and last rows of Gypframe RB SureFix Bars are located at all wall perimeters. Boards are fixed to the underside of Gypframe RB SureFix Bars with long board edges at right angles to the bars. When fixing boards, care must be taken to ensure that the plasterboard fixing screws do not make contact with the joists. Indirect fix to Gypframe RB Resilient Bars The procedure is similar to that for Gypframe RB SureFix Bars. For full installation details, refer to the British Gypsum SiteBook or visit 9

5 Performance ( Refer to - Basic principles of system design) Table direct fix to new or existing solid timber joist floors Detail Board Ceiling lining Noggings Sound insulation System type thickness required R w L nw reference Airborne Impact mm db db EN mm t&g (softwood or chipboard) floor boarding over 8 x 9mm (minimum) timber joists at 600mm centres, with suitable timber noggings between joists to support board edges (where indicated). Linings as in table. 0 minutes fire resistance EN WallBoard x No 0 79 C0609 MultiBoard x 0 Yes - - C minutes fire resistance EN mm t&g (softwood or chipboard) floor boarding over 8 x 9mm (minimum) timber joists at 600mm centres, with suitable timber noggings between joists to support board edges. Linings as in table. FireLine x. Yes 0 76 C06009 WallBoard (inner layer). + Yes 0 76 C FireLine (outer layer) MultiBoard x 0 Yes - - G minutes fire resistance EN mm t&g (softwood or chipboard) floor boarding over 8 x 9mm (minimum) timber joists at 600mm centres (maximum), with suitable timber noggings between joists to support board edges. Linings as in table. FireLine x. Yes 0 76 C060 MultiBoard x 0 Yes - - G0607 At perimeter only. At perimeter and to support outer layer ceiling board joints (8 x 8mm minimum). If centres are less than 600mm, then 8mm t&g floor boarding can be used. Maximum permissible timber grade at 00% load ratio C, except for single layer Gyproc WallBoard construction which is C6. NB The fire resistance and sound insulation performances are for imperforate partitions, walls and ceilings incorporating boards with joints taped and filled, or skimmed according to British Gypsum s recommendations. The quoted performance are achieved only if British Gypsum components are used throughout, and the Company s fixing recommendations are strictly observed. Any variation in the specifications should be checked with British Gypsum. Where boards are fixed direct to timber joists, screw-fixing is the preferred alternative to nail-fixing and minimises the risk of fixing defects occurring. 0 NBS work section K0 - Plasterboard drylinings / partitions / ceilings; K - Rigid sheet flooring / sheathing / sarking / decking / linings / castings; and K0 - Timber board flooring / sarking / linings / castings

6 T F E bgtechnical.enquiries@bpb.com Table indirect fix to new or existing solid timber joist floors Detail Board Ceiling lining Estimated laboratory sound insulation System type thickness R w (R w + Ctr) L nw reference Airborne Impact mm db db EN mm t&g (softwood or chipboard) floor boarding over 8 x 9mm (minimum) timber joists at 600mm centres. Gypframe RB SureFix Bars fixed to underside of joists at 0mm centres with ceiling linings (see table) fixed into the bars only. 0 minutes fire resistance EN WallBoard x. - C minutes fire resistance EN mm t&g (softwood or chipboard) floor boarding over 8 x 9mm (minimum) timber joists at 600mm centres. Gypframe RB Resilient Bars fixed to underside of joists at 0mm centres with ceiling linings (see table) fixed into the bars only. FireLine x. - C060 SoundBloc x 60 C06009 SoundBloc x 6 () C0600 If centres are less than 600mm, then t&g floor boarding can be used. Maximum permissible timber grade at 00% load ratio C. Typical platform floor construction (comprising walking surface of 8mm t&g wood board flooring, spot-bonded with Gyproc Sealant at 00mm centres to a substrate of Gyproc Plank laid on mm Isowool Sound Deadening Floor Slabs - Rigid Grade, laid on a minimum of mm wood-based sheet sub-deck nailed to the joists) over 8 x 9mm (minimum) timber joists at 600mm centres. Gypframe RB SureFix Bars fixed to underside of joists at 0mm centres with ceiling linings (see table) fixed into the bars only. 00mm Isowool General Purpose Roll in the cavity. mm t&g (softwood or chipboard) floor boarding over 8 x 9mm (minimum) timber joists at 600mm centres. Gypframe RB Resilient Bars fixed to underside of joists at 0mm centres with ceiling linings (see table) fixed into the bars only. 00mm Isowool General Purpose Roll in the cavity. NB The fire resistance and sound insulation performances are for imperforate partitions, walls and ceilings incorporating boards with joints taped and filled, or skimmed according to British Gypsum s recommendations. The quoted performance are achieved only if British Gypsum components are used throughout, and the Company s fixing recommendations are strictly observed. Any variation in the specifications should be checked with British Gypsum. Where boards are fixed direct to timber joists, screw-fixing is the preferred alternative to nail-fixing and minimises the risk of fixing defects occurring. NBS work section K0 - Plasterboard drylinings / partitions / ceilings; K - Rigid sheet flooring / sheathing / sarking / decking / linings / castings; and K0 - Timber board flooring / sarking / linings / castings

7 Performance ( Refer to - Basic principles of system design) EN Table direct fix to joists / bottom chord of trusses below the roof space 8 x 0mm (minimum) joists / chords at 600mm (maximum) centres. Insulation and ceiling linings as in table. Detail Board Ceiling lining Insulation Insulation System type thickness type thickness reference mm mm 0 minutes fire resistance EN WallBoard x Isowool General Purpose Roll 0 C060 FireLine x. Stone mineral wool (kg/m ) 0 C0608 WallBoard x Stone mineral wool (kg/m ) 0 C060 NB The fire resistance and sound insulation performances are for imperforate partitions, walls and ceilings incorporating boards with joints taped and filled, or skimmed according to British Gypsum s recommendations. The quoted performance are achieved only if British Gypsum components are used throughout, and the Company s fixing recommendations are strictly observed. Any variation in the specifications should be checked with British Gypsum. Where boards are fixed direct to timber joists, screw-fixing is the preferred alternative to nail-fixing and minimises the risk of fixing defects occurring. NBS work section K0 - Plasterboard drylinings / partitions / ceilings; K - Rigid sheet flooring / sheathing / sarking / decking / linings / castings; and K0 - Timber board flooring / sarking / linings / castings

8 T F E bgtechnical.enquiries@bpb.com BS mm t&g (softwood or chipboard) floor boarding over timber joists (min 8mm) at 600mm centres with suitable timber noggings between joists to support board edges. Linings as in table. Detail Board type Ceiling lining Sound insulation System thickness R w L nw reference Airborne Impact mm db db 0 minutes fire resistance BS WallBoard x 0 - C0609 WallBoard x - C minutes fire resistance BS WallBoard x >0 76 C06006 The acoustic ratings quoted above are based on 00mm deep joists and a walking surface of min. 9.6kg/m. This is based on a test with a typical I joist. For I joists by specific manufacturers, consult them direct. Estimated. Table - direct fix plasterboard to new or existing solid timber joist or I joist floors mm t&g (softwood or chipboard) floor boarding over timber joists (min 8mm) at 600mm centres with suitable timber noggings between joists to support board edges. Linings as in table. mm t&g (softwood or chipboard) floor boarding over timber joists (min 8mm) at 0mm centres with suitable timber noggings between joists to support board edges. Linings as in table. mm t&g (softwood or chipboard) floor boarding over timber I joists (min 8mm) at 600mm centres with suitable timber noggings between joists to support board edges. Linings as in table. WallBoard (inner layer). + >0 76 C FireLine (outer layer) FireLine x. >0 76 C06009 Plank (inner layer) 9 +. >0 7 C WallBoard (outer layer) 90 minutes fire resistance BS FireLine x >0 - C00 NB The fire resistance and sound insulation performances are for imperforate partitions, walls and ceilings incorporating boards with joints taped and filled, or skimmed according to British Gypsum s recommendations. The quoted performance are achieved only if British Gypsum components are used throughout, and the Company s fixing recommendations are strictly observed. Any variation in the specifications should be checked with British Gypsum. Where boards are fixed direct to timber joists, screw-fixing is the preferred alternative to nail-fixing and minimises the risk of fixing defects occurring. NBS work section K0 - Plasterboard drylinings / partitions / ceilings; K - Rigid sheet flooring / sheathing / sarking / decking / linings / castings; and K0 - Timber board flooring / sarking / linings / castings

9 Performance ( Refer to - Basic principles of system design) mm t&g (softwood or chipboard) floor boarding over timber joists (min 8mm) at 600mm centres. Gypframe RB Resilient Bars at 0mm centres to underside of joists. 00mm Isowool APR 00 in the cavity. Linings as in table. mm t&g (softwood or chipboard) floor boarding over timber joists (min 8mm) at 600mm centres. Gypframe RB SureFix Bars at 0mm centres to underside of joists. Linings as in table. Detail Board type Ceiling lining Sound insulation System thickness R w L nw reference Airborne Impact mm db db BS Table - indirect fix plasterboard to new or existing solid timber joist floors 0 minutes fire resistance BS WallBoard x. - C minutes fire resistance BS Plank (inner layer) C WallBoard (outer layer) Plank (inner layer) C SoundBloc (outer layer) The acoustic ratings quoted above are based on 00mm deep joists and a walking surface of min. 9.6kg/m. NB The fire resistance and sound insulation performances are for imperforate partitions, walls and ceilings incorporating boards with joints taped and filled, or skimmed according to British Gypsum s recommendations. The quoted performance are achieved only if British Gypsum components are used throughout, and the Company s fixing recommendations are strictly observed. Any variation in the specifications should be checked with British Gypsum. Where boards are fixed direct to timber joists, screw-fixing is the preferred alternative to nail-fixing and minimises the risk of fixing defects occurring. NBS work section K0 - Plasterboard drylinings / partitions / ceilings; K - Rigid sheet flooring / sheathing / sarking / decking / linings / castings; and K0 - Timber board flooring / sarking / linings / castings

10 T F E bgtechnical.enquiries@bpb.com BS Table 6 - direct fix non-combustible linings to new or existing solid timber joist floors 8mm t&g (softwood or chipboard) floor boarding over timber joists (min 8mm) at 0mm centres with suitable noggings between joists to support board edges. Linings as in table. mm t&g (softwood or chipboard) floor boarding over timber joists (min 8mm) at 600mm centres with suitable noggings between joists to support board edges. Linings as in table. 6 mm t&g (softwood or chipboard) floor boarding over timber joists (min 7mm) at 600mm centres with suitable noggings between joists to support board edges 00mm. Isowool APR 00 in the cavity. Linings as in table mm t&g (softwood or chipboard) floor boarding over timber joists (min 8mm) at 600mm centres. mm stone mineral wool (8kg/m ) in the cavity. Linings as in table. 8mm t&g (softwood or chipboard) floor boarding over timber joists (min 0mm) at 00mm centres. 0mm stone mineral wool (6kg/m ) in the cavity. Linings as in table. mm t&g (softwood or chipboard) floor boarding over timber joists (min 8mm) at 600mm centres. Linings as in table. mm t&g (softwood or chipboard) floor boarding over timber joists (min 7mm) at 600mm centres with suitable noggings between joists to support board edges. Linings as in table. mm t&g (softwood or chipboard) floor boarding over timber joists (min 0mm) at 600mm centres with suitable noggings between joists to support board edges. 60mm stone mineral wool (kg/m ) in the cavity. Linings as in table. mm t&g (softwood or chipboard) floor boarding over timber joists (min 8mm) at 600mm centres. 00mm Isowool APR 00 in the cavity. Linings as in table. Detail Board type Ceiling lining System thickness reference mm 0 minutes fire resistance BS MultiBoard x. G009 MultiBoard x. G minutes fire resistance BS MultiBoard x 0 G060 MultiBoard x 0 G060 80mm wide MultiBoard strip + MultiBoard G mm wide MultiBoard strip + MultiBoard G0606 FireCase S (screw-fixed) x G mm MultiBoard strip + MultiBoard 0 +. G minutes fire resistance BS 8 9 MultiBoard + 00mm MultiBoard strip + MultiBoard. +. G0607 MultiBoard + 00mm MultiBoard strip + MultiBoard. +. G0608 Use 8mm Glasroc FireCase Screws at 0mm centres. 8mm x 8mm timber noggings are also required between joists and at the perimeter to support board edges. NB The fire resistance and sound insulation performances are for imperforate partitions, walls and ceilings incorporating boards with joints taped and filled, or skimmed according to British Gypsum s recommendations. The quoted performance are achieved only if British Gypsum components are used throughout, and the Company s fixing recommendations are strictly observed. Any variation in the specifications should be checked with British Gypsum. Where boards are fixed direct to timber joists, screw-fixing is the preferred alternative to nail-fixing and minimises the risk of fixing defects occurring. NBS work section K0 - Plasterboard drylinings / partitions / ceilings; K - Rigid sheet flooring / sheathing / sarking / decking / linings / castings; and K0 - Timber board flooring / sarking / linings / castings

11 Performance ( Refer to - Basic principles of system design) Table 7 - compartment / separating solid timber joist and sub-joist floors Typical platform floor construction (comprising walking surface of 8mm t&g wood board flooring, spot-bonded with Gyproc Sealant at 00mm centres to a substrate of Gyproc Plank laid on mm Isowool Sound Deadening Floor Slabs - Rigid Grade, laid on a minimum of mm wood-based sheet sub-deck nailed to the joists) over timber joists (minimum mm) at 600mm centres. 00mm Isowool APR 00 between the joists. Linings as in table. Separating sub-joist floor comprising of a platform floor construction (comprising walking surface of 8mm t&g wood board flooring, spotbonded with Gyproc Sealant at 00mm centres to a substrate of Gyproc Plank laid on mm Isowool Sound Deadening Floor Slabs - Rigid Grade, laid on a minimum of mm wood-based sheet sub-deck nailed to the joists) over timber joists (minimum 7mm) at 600mm centres. 00mm Isowool APR 00 in the cavity. Linings as in table. Detail Board type Ceiling lining Sound insulation System thickness R w (R w + Ctr) L nw reference Airborne Impact mm db db db BS 60 minutes fire resistance BS Plank (inner layer) (0) 6 C SoundBloc (outer layer) SoundBloc x 66 () 8 C0600 NB The fire resistance and sound insulation performances are for imperforate partitions, walls and ceilings incorporating boards with joints taped and filled, or skimmed according to British Gypsum s recommendations. The quoted performance are achieved only if British Gypsum components are used throughout, and the Company s fixing recommendations are strictly observed. Any variation in the specifications should be checked with British Gypsum. Where boards are fixed direct to timber joists, screw-fixing is the preferred alternative to nail-fixing and minimises the risk of fixing defects occurring. NBS work section K0 - Plasterboard drylinings / partitions / ceilings; K - Rigid sheet flooring / sheathing / sarking / decking / linings / castings; and K0 - Timber board flooring / sarking / linings / castings 6

12 T F E bgtechnical.enquiries@bpb.com Timber joists (min 8mm) or bottom chord of trusses (min mm) at 600mm centres, with suitable timber noggings between joists to support board edges. Insulation laid between joists (see table). Linings as in table. Detail Board type Ceiling lining Insulation System thickness type reference mm 0 minutes fire resistance BS MultiBoard x. 0mm Isowool General Purpose Roll G060 BS Table 8 - direct fix to joists / bottom chord of trusses below the roof space WallBoard x. 0mm Isowool General Purpose Roll C0609 FireLine x. 0mm Isowool General Purpose Roll C0607 WallBoard x. 00mm Isowool General Purpose Roll C minutes fire resistance BS CasoLine MF suspended from joists. Insulation laid over ceiling grid. MultiBoard x 0 0mm Isowool General Purpose Roll G060 FireLine x. 0mm stone mineral wool (kg/m ) C0608 FireLine x 0mm stone mineral wool (kg/m ) C060 Nominal 0mm x mm timber battens should be fixed to the side of timber supports where the ceiling boards butt in order to maintain an adequate bearing surface. NB The fire resistance and sound insulation performances are for imperforate partitions, walls and ceilings incorporating boards with joints taped and filled, or skimmed according to British Gypsum s recommendations. The quoted performance are achieved only if British Gypsum components are used throughout, and the Company s fixing recommendations are strictly observed. Any variation in the specifications should be checked with British Gypsum. Where boards are fixed direct to timber joists, screw-fixing is the preferred alternative to nail-fixing and minimises the risk of fixing defects occurring. NBS work section K0 - Plasterboard drylinings / partitions / ceilings; K - Rigid sheet flooring / sheathing / sarking / decking / linings / castings; and K0 - Timber board flooring / sarking / linings / castings 7

13 Performance ( Refer to - Basic principles of system design) Table 9 - U-values for room-in-the-roof constructions in new-build and refurbishment New-build room-in-the-roof Tiled or slated roof on tiling battens on breather membrane on softwood rafters at 600mm centres. Insulation installed between rafters (see table). Gyproc ThermaLine laminate fixed to the underside of rafters (see table). Refurbishment room-in-the-roof Tiled or slated roof on tiling battens on sarking felt on softwood rafters at 600mm centres. Insulation installed between rafters (see table) maintaining a 0mm ventilated air space above the insulation. Gyproc ThermaLine laminate fixed to the underside of rafters (see table). Detail Insulation Insulation Thermal laminate Thermal laminate U-value type thickness type thickness mm mm W/m K Isowool Frame Batt 0 00 ThermaLine SUPER Isowool Frame Batt 0 0 ThermaLine SUPER Isowool Frame Batt HP 0 0 ThermaLine SUPER Proprietary roof insulation slab 7 ThermaLine SUPER R=. W/m K min Isowool Frame Batt 0 0 ThermaLine SUPER NB The fire resistance and sound insulation performances are for imperforate partitions, walls and ceilings incorporating boards with joints taped and filled, or skimmed according to British Gypsum s recommendations. The quoted performance are achieved only if British Gypsum components are used throughout, and the Company s fixing recommendations are strictly observed. Any variation in the specifications should be checked with British Gypsum. Where boards are fixed direct to timber joists, screw-fixing is the preferred alternative to nail-fixing and minimises the risk of fixing defects occurring. NBS work section K0 - Plasterboard drylinings / partitions / ceilings; K - Rigid sheet flooring / sheathing / sarking / decking / linings / castings; and K0 - Timber board flooring / sarking / linings / castings 8

14 T F E bgtechnical.enquiries@bpb.com Design Planning - key factors To minimise the risk of ceiling finish defects occurring, seasoned timber with a moisture content not exceeding that recommended in BS 68: Part : 99 should be used. The contractor should ensure that timber supports are accurately spaced, aligned, and levelled. Gyproc Drywall Timber Screws are the preferred method of fixing. Cavity fire barriers Cavity barriers may be required to satisfy the requirements of national Building Regulations. Refer to 7 Cavity fire barriers. Strength and robustness Timber should be aligned and level, and should meet the requirements of BS 68: Part : 99. The dimensions and assembly of timber supports should be sufficient to allow positive fixing of boards without bounce or undue deflection because of the nailing, screwing, or other applied force. When the above fixing conditions cannot be met, a timber batten should be securely fixed to the side of those timber supports where ceiling boards butt, in order to increase the bearing surface. Where boards are fixed at maximum centres in adverse conditions the standard of lining can be affected. Adverse conditions can generally be described as conditions where high humidity occurs, principally in the cold, damp, autumn / winter period. They also refer to buildings under construction during this period where both the structure and wet applications such as plastering and screeding are subject to slow drying conditions. Where a vapour control layer is included in the ceiling construction in conditions described previously, condensation can form on the vapour control surface. This can result in plasterboard becoming unduly damp, and affecting the standard of acceptability of the lining and any applied plaster or textured coating. In these circumstances increased ventilation or dehumidifiers is recommended. Water vapour control Where there is a requirement for a vapour control layer, DUPLEX grade Gyproc plasterboards should be specified as the face layer (i.e. the second layer in double layer linings). The application of two coats of Gyproc Drywall Sealer to the face lining will also provide vapour control. Refer also to Timber noggings. Acoustic performance Airtightness is essential for optimum sound insulation. While most junctions will be sealed with standard finishing materials, gaps at the perimeter of the floor and ceiling, and other small airpaths, can be sealed using Gyproc Sealant. Imposed loads The designer should ensure that the floor construction is suitable to support any imposed loads. Timber noggings Suitable timber noggings, normally 8mm x 8mm, may be required between joists and at the perimeter to support board edges, and to maintain vapour control and fire resistance where indicated. The provision of noggings depends on the thickness of boards used, and the spacing of timber joists (please see Table 0). Noggings are not required for mm boards with joists spaced at 600mm centres. Timber noggings should always be provided at the perimeter except when using mm board or 9mm Gyproc Plank. When fixing DUPLEX grade Gyproc plasterboards or thermal laminates providing vapour control, however, noggings are required regardless of joist spacing or board thickness in order to ensure that vapour control integrity is maintained. Table 0 - Provision of timber noggings Board Maximum joist centres thickness with noggings without noggings mm mm mm Thermal laminates Joist width Where joist width is less than the minimum stated in Tables 8, the system may not meet its specified performance. Where minimum fixing tolerances cannot be met e.g. the inadequate bearing surface afforded by mm width trussed rafters, 0mm x mm timber battens should be screw-fixed to the side of the joists where ceiling boards abut in order to extend the bearing surface (see Construction detail 8). Nail popping Loosening of nails in timber can occur through timber shrinkage (see Construction detail 7), or as a result of fixing boards to misaligned or twisted framing. To reduce the risks, boards should be fixed tight to framing members. To minimise any risk of fixing defects occurring, use Gyproc Drywall Timber Screws. If nails are the preferred fixing method, the risk of subsequent fixing defects can occur. This can be eliminated by fixing Gypframe RB SureFix Bar to the underside of timber joists to provide a positive ground for screw-fixing the ceiling linings. In tests where joists warped and twisted under drying shrinkage, Gypframe RB SureFix Bar was successful in providing a sound base for plasterboard fixing, resulting in no fixing defects. Gypframe RB SureFix Bar also contributes to the sound insulation of a timber joist floor. The performance of the floor in practice will generally be governed by flanking transmission. Refer to Basic principles of system design. Please refer to - Basic principles of system design for general guidance 9

15 Fixing to super-dried timber and engineered I beams Test results show that Gyproc Drywall Timber Screws are the best solution for fixing to standard softwood, super-dried timber (approximately % moisture content) and engineered timber I beams. When engineered timber I beams or timber joists are used in conjunction with a metal framed partition such as GypWall RAPID, the contractor may wish to use Gyproc Drywall Screws for both applications (similar lengths are available). Services Electrical and other small service runs can be routed within the floor cavity. The installation of electrical services should be carried out to BS 767: 99, and the recommendations of the Institution of Electrical Engineers. Concealed cables may need earthed metallic covering, or to be enclosed in earthed conduit, trunking, or ducting to satisfy BS 767: 99. Fixtures / fittings Fixtures should be made into joists, or to supplementary timber. Board finishing Refer to 0 Finishing systems and decorative effects. Further guidance Good practice guidance to minimise the risk of installation and fixing defects occurring is given in the Technical Information Sheet TI-008 Fixing specification for Gyproc plasterboard to timber framed ceilings and walls. Please contact the British Gypsum Drywall Academy Advice Centre for a copy, alternatively visit For general advice on timber frame constructions, please contact The UK Timber Frame Association Ltd. Kinnerton Place South The e-centre London Cooperage Way Business SWX 8EH Village, Alloa, FK0 LP Tel: Tel: Fax: 09 7 Website: office@timber-frame.org Please refer to - Basic principles of system design for general guidance. 0

16 T F E bgtechnical.enquiries@bpb.com Construction details Ceiling plan - joists at 0mm centres using.mm Gyproc WallBoard - noggings to support board edges are not required 900 mm 00 mm 800mm 0mm Ceiling plan - joists at 600mm centres using.mm Gyproc WallBoard - noggings to support board edges are required 00mm 600mm Timber joists Noggings to support board edges Noggings to provide support at the perimeter Gyproc WallBoard Gyproc Drywall Timber Screws at 0mm centres

17 600 mm Ceiling plan - joists at 600mm centres using mm Gyproc WallBoard - noggings to support board edges are not required. 900 mm 800mm Ceiling plan - joists at 60mm / 06mm centres (equivalent to / 6 imperial) using.mm Gyproc HandiBoard - noggings to support board edges are required / not required respectively 0mm 600mm 60mm Gyproc Drywall Timber Screws at 0mm centres Timber joists Noggings to support board edges Noggings to provide support at the perimeter.mm Gyproc HandiBoard

18 T F E bgtechnical.enquiries@bpb.com Ceiling plan - Gypframe RB SureFix Bar fixed to underside of timber joists or bottom chord of trusses (arrangement for the fixing of.mm lining illustrated) 6 600mm 0 mm 7 Twisting of standard softwood timber joist on drying from 8 0% to 8% moisture content Wall junction / partition head detail with Gypframe RB SureFix Bar to the underside of the timber joists Increasing the bearing surface when fixing boards to trussed rafters mm mm Timber joists 6 GypWall partition Gypframe RB SureFix Bars 7 Gyproc plasterboard lining Gypframe RB SureFix Bars at perimeter noggings Wall structure Gyproc Drywall Timber Screw 8 9 Gyproc plasterboard ceiling Timber batten ( x 0mm)