Technical Tips

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GIB® Fire Rated Systems Supplement

GIB® Fire Rated Systems Supplement PDF

After release of the GIB® Fire Rated Systems literature last year our technical team has committed to ongoing development and continually looked for ways to offer improved systems and details for both designers and installers.

The GIB® Fire Rated Systems Supplement is a live document available on the GIB® website which collates any updates, changes and new information. From time to time technical contents will be uploaded and communicated to the market via this document.

In addition to the range of GIB® Fire Rated Systems available, based on recent full-scale furnace testing, the supplement now includes specification GBS90a, a new two-way non-loadbearing 90 minute FRR steel stud system.

Furthermore, due to increasing demand and enquiries on junction details between GIB® Fire Rated Systems and structural flooring systems such as ComFlor®, Stahlton Rib and In-fill and Double Tee which are commonly used in a wide variety of commercial and residential applications, the applicable details have been developed for each type of flooring systems and uploaded into the supplement.

If you want to be notified when technical updates are made, you can simply sign up to the GIB® database via the website.

GIB® Fire Rated Systems Literature

New GIB® Fire Rated Systems Literature Out Now 

Good fire design requires coordination and collaboration between a number of parties from the fire engineer to architect, contractor and sub-contractors like data installers.  With the release of the new GIB® Fire Rated Systems Literature, we aim to help reduce confusion in the market about fire rated systems and provide good guidance on issues that commonly come up when dealing with fire.

The GIB® Fire Rated Systems Literature is already a core resource for the design and detailing of fire rated systems within New Zealand.  This update adds a range of new tested GIB® systems including the inclusion of 10 minute smoke separation walls, and timber and steel systems offering FRRs of between 30 minutes and 240 minutes.

In addition to a wider range of systems, Winstone Wallboards has released a new product:  GIB Fire Soundseal®.  GIB Fire Soundseal® is a single component, non-sag, acrylic based interior sealant for use where specified in GIB® Fire Rated Systems and where GIB Soundseal® is specified in GIB Noise Control® Systems.

Additional or clarified guidance has been included on NLB steel stud heights, top-down fire exposure design, and use of metal components within suspended ceiling grid systems.  Many junction details have been clarified or added including new deflection head details.

The new GIB® Fire Rated Systems Literature and summary document outlining the key changes is available for download from the GIB® website.  Copies of the literature can also be requested through gib.co.nz

GIB®Site Guide

New GIB® Site Guide Available Now

An update to the GIB® Site Guide is now available.

The new edition released in September 2018 includes the latest updates to GIB® product and systems as well as:

  • Updated interior quality of finish information
  • Improved guidance on using GIB® delivered to site services
  • Improved guidance on selecting and using the GIB® compound range

The updated guide also provides detailed installation guidance on working with GIB EzyBrace® and GIB Aqualine® Wet Area Systems.

Request a Hard copy of the GIB® Site Guide from info@gib.co.nz

Download a copy of the GIB® Site Guide from the website at www.gib.co.nz

Access on the go the GIB® Site Guide using the GIB® App.

  

 

Interior Finishing – The fundamentals of a good finish

New GIB® Interior Finishing - The fundamentals of a quality finish 

No matter how smooth wall and ceiling linings appear, they will never be 100% physically flat and blemish free. This applies to any interior surface comprising jointed sheet type material including fibrous plaster, plywood, MDF, plasterboard and even glass. All of these substrate materials contain physical deviations or minor blemishes.

Although it is impossible to get a perfectly physically flat or blemish free interior surface, it is possible to achieve ‘the appearance’ of blemish free flatness.

The type of decoration applied to the wall or ceiling surface also has an impact on the perceived quality. Modern interior design using smooth-painted surfaces will highlight imperfections more than if texture or wallpapers are used.

The tips in this document will help make any surface imperfections less visible.

1) DRY AND STRAIGHT FRAMING 

The final finish quality of a GIB® plasterboard wall or ceiling is heavily influenced by the quality of the framing to which the GIB® plasterboard is fixed. If framing is not straight and aligned, it will be reflected in the finished appearance of the wall or ceiling. Any timber framing must also be dry prior to the GIB® plasterboard being installed otherwise the framing may shrink or twist as it dries and cause cracks, nail pops and other problems in plasterboard linings. Alternatively steel framing can be used.

2) METAL CEILING BATTENS 

The use of GIB® Rondo® metal ceiling battens is recommended on all ceilings rather than timber ceiling battens. Because GIB® Rondo® metal ceiling battens hold no moisture they will not bend, twist or warp and therefore help to achieve and maintain a straight and true ceiling.

3) 13MM CEILING LININGS 

It is recommended that 13mm GIB® plasterboard is used on all ceilings throughout your project. A thicker stronger 13mm GIB® plasterboard gives you extra rigidity to help fight the effects of gravity and structural movement. If 10mm plasterboard is chosen, then it must be fixed to battens spaced at maximum 450mm centres on ceilings. However, the extra rigidity of 13mm GIB® plasterboard enables you to have ceiling battens spaced up to 600mm apart. Because there are fewer ceiling battens, fewer fasteners are required, resulting in fewer points where imperfections could be visible.

4) HORIZONTAL FIXING 

Any imperfections will be most noticeable at the joints of wall linings so it pays to keep these joints to a minimum. Fixing GIB® plasterboard sheets horizontally instead of vertically on walls reduces the number of joints, helping to achieve a more uniform appearance. Horizontal fixing also means that glancing light from adjacent windows shines along the joint, thus reducing the “shadowing” effect that is sometimes noticeable with vertical fixing (see diagram below). With horizontal fixing, there is only one joint which is below eye level.

5) CHOOSE THE RIGHT DECORATIVE FINISH 

Semi-gloss, gloss and even low sheen paints all reflect light and tend to accentuate even the smallest surface imperfection. On the other hand, flat or matte paints tend to reflect light back in a diffused form and better disguise any surface irregularity. Avoid semi-gloss and gloss paints where you can. Even when the work is carried out by a highly skilled tradesperson, the end result may be disappointing. Dark colours also highlight the slightest imperfections, whereas lighter colours tend to soften the effect of any irregularities by absorbing less light.

6) MINIMISE CRITICAL LIGHTING 

Lighting sources can include windows, skylights and artificial wall or ceiling washer lights. Critical lighting should be avoided where possible. If it cannot be avoided it needs to be accepted that some imperfections may be visible under extreme lighting conditions. A degree of agreement, co-operation, acceptance and tolerance is required between parties. Lighting design is vitally important in minimising the visibility of any minor imperfections because it’s the lighting conditions that create the “shadow” that makes any imperfection visible. Lighting design will either accentuate or diminish the visibility of any imperfections.

CRITICAL LIGHTING 

When light strikes a surface at a shallow angle it tends to greatly exaggerate any surface irregularities and this is termed “critical lighting”. However, when the angle of light is more or less at right angles to a surface, imperfections are less obvious and this is termed “noncritical lighting”.

RECESSED DOWNLIGHTS AND LIGHT SHADES  

Incorporating recessed downlights or light shades help to channel light downwards and reduce the amount of glancing or critical light.

WINDOW POSITIONING AND SHADES 

Avoid positioning narrow windows hard up against the end of a wall or ceiling, particularly on long walls or ceilings at the end of a room or hallway. Making a window wider and placing it away from the room corner should reduce the critical lighting effect. Try not to take windows right up to ceiling level. Provide sunshades over the window or recess the window to stop the sunlight reaching the wall.

AVOID SPOT LIGHTS 

Avoid spot lighting or wall mounted up-lighting or be careful about where these lights are directed and the angle at which they hit a surface particularly near jointing.

LEVELS OF FINISH 

Levels of Finish assist in specifying the required quality of finish when installing and stopping plasterboard. Level 4 and 5 finishes are commonly specified in residential construction. Level 4 finish is the generally accepted level of finish for a residential home. It is used where non-critical lighting falls on satin/flat/low sheen paints, or where critical lighting illuminates wallpaper or textured finishes. Level 5 finish is for use where gloss or semi-gloss paints are specified or where critical lighting conditions occur on satin, flat or low sheen paints.

COLOUR TRICKS AND LIGHT 

Colour is a magical property that can transform an environment, create a style and set a tone. By using colour you can make dramatic statements in your home and express your own personal creativity. Tricks with colour can be achieved to make your home appear spacious or light. There are plenty of tricks you can use to enhance the size of your rooms, and on the other hand, if you have a space that you want to look warmer, careful use of colour can offer a simple but effective way to make your home feel cosier. If you want something a little out of the ordinary, different paint techniques can be used to create a wonderful variety of textured effects and they offer an exciting alternative to plain painted walls or wallpaper. These include colour washing, sponging, limewash effects, rag rolling and added sparkle.

LIGHTING AS ART 

Light has the power to characterise and accent rooms. It can convey an aura of intimacy, provide a touch of sophistication and enhance a home’s architectural details with special effects. Good lighting is about more than just light levels. The same level of light can provide effective or ineffective lighting. Some lighting can make rooms flat and featureless even when it’s bright. An efficient and effective lighting system will:

  • Provide a high level of visual comfort
  • Make use of natural light
  • Provide the best light for the tasks commonly undertaken in that space
  • Provide controls for flexibility (eg dimmers)
  • Have low energy requirements

A lighting designer will be able to help you design an effective lighting scheme. Ensure you have a detailed lighting plan before construction so that all wiring, cabling and factors influencing quality of finish can be allowed for. As explained in ‘Fundamentals of a Quality Finish’ the choice of decorative colour and lighting can have an adverse impact on the flat appearance of interior walls and ceilings.

These decisions must to be considered at the design stage of the project so the level of expectation of the interior finish can best be delivered by all parties.

The Finishing Process 

The process of installing GIB® plasterboard involves a number of steps and tradespeople. To create a quality finish all trades need to deliver a professional job at each step in order that the next step can be effectively completed. Fixing GIB® plasterboard should be fixed horizontally where possible using GIBFix® adhesive plus GIB® Grabber® screws.

1) BASECOAT AND TAPING (STOPPING) 

The joint is first covered with a GIB® basecoat compound with GIB® paper tape embedded in the compound to strengthen the joint. Once the base coat is dry, a second layer of compound is added to fill the tapered joint void.

2) TOPCOAT COMPOUND 

A final GIB® topcoat compound finishes the jointing process to deliver a smooth sandable surface. Choosing the appropriate ready-mixed compound for the application is critical to prepare for the sanding and painting step.

3) SANDING AND PAINTING 

The final part of the process, once the compound is fully set and dried, is to sand back the surface to a smooth finish. The wall or ceiling surface is then ready for painting or wallpapering. Facts about Jointing Prior to the application of the paint or wallpaper, joint compounds must be allowed to adequately ‘cure’ in order to prevent shrinkage and to deliver the required performance in adhesion and joint strength. There are three variables that affect the speed of ‘cure’ :

  • Air temperature
  • Relative air humidity
  • Movement of air

On a still cold wet day (10oC/90% humidity) there will be minimal drying of GIB® compounds. In comparison on a windy hot dry day (25oC/50% humidity) the air will have 12 times the capacity to carry water and will be substantially more effective in the ‘curing’ process. A temperature of not less than 10oC is required to ensure that the resins in GIB® compounds cure and to support the evaporation of water.

Finishing to NZ Standards 

When a contractor is engaged to undertake fixing and/or stopping of GIB® Plasterboard it will usually be under the prescribed standards of either NZS 3604:2011 or more specifically AS/NZS 2589:2017. These standards instruct in detail minimum coverages of the layers of compounds and preparation quality. It is important to note that there is a section which specifically addresses the ‘Correct assessment of the surface condition at handover’ (section 4.7). Correct position and distances from surfaces for viewing and intensity of working lights are discussed and references to MBIEs ‘Guide to tolerances’ are made.

It is important to keep in mind that jointing of plasterboard is a manual task which results in a slightly raised area over fasteners and joints. Typically industry norm is that the maximum allowable deviation in the build-up is less than 2mm across the joint, giving a non-flat finish that can be highlighted.

For further information go to gib.co.nz or contact the GIB® Helpline on 0800 100 442.