1. GENERAL

Related work

1.1 RELATED SECTIONS
For ~ refer to 

Documents 

1.2 DOCUMENTS REFERRED TO
Documents referred to in this section are: 

NZBC D1/AS1 Access routes
2.1 Slip resistance

AS/NZS 1859 Reconstituted wood-based panels
1859.4: Hardboard
AS/NZS 1860 Particleboard flooring
1860.1: Specifications
AS/NZS 2269 Plywood - Structural
AS/NZS 3661 Slip resistance of pedestrian surfaces
3661.1: Requirements

BRANZ Bulletin 330: Thin flooring materials - 2 Preparation and laying

Documents listed above and cited in the clauses that follow are part of this specification. However, this specification takes precedence in the event of it being at variance with the cited document.

1.3 MANUFACTURER'S DOCUMENTS
Kahrs and supplier's documents relating to work in this section are:
Copies of the above literature can be obtained by phoning The Wooden Floor Company on Freephone 0800 484 949.

Requirements

1.4 SAMPLES
Submit on request samples of the flooring specified sufficient to show the pattern and the range of colour finish.

1.5 QUALIFICATIONS
Carry out all work using The Wooden Floor Company installers who are competent and experienced in this type of floor laying work.

Guarantees

1.6 WARRANTY
Warrant this work under normal environmental and use conditions against failure:
Kährs warranty period: 30 years Kährs standard guarantee
Kährs Linnea warranty period: 12 years Kährs Linnea standard guarantee
From: Date of installation 

Performance

1.7 SLIP RESISTANCE
To comply with NZBC acceptable solution D1/AS1, clause 2.1. 
Sheet and tiles, when in place on a level access route, to have a mean coefficient of friction not less than 0.4 when tested in accordance with AS/NZS 3661.1, appendix A and B.
Sheet and tiles, when in place on a sloping access route, to have a coefficient of friction of not less than 0.4 x 0.0125S (where S is the slope of the walking surface expressed as a percentage).

1.8 CERTIFICATES
Provide certificates and any other evidence that the flooring will comply with the standard of performance specified.

1.9 CERTIFICATES, SLIP RESISTANCE
Provide certificates and any other evidence at the time of selection/supply that the completed flooring work will comply with NZBC acceptable solution D1/AS1.

1.10 TESTING
Sample and test the substrate to BRANZ Bulletin 330 to ensure that moisture content is within the limits specified. Provide a written record.

2. PRODUCTS 

Materials

2.1 CONSTRUCTION PLYWOOD UNDERLAY
Rotary cut radiata pine veneer ply, face sanded, treated H1 and to AS/NZS 2269.

2.2 HARDBOARD UNDERLAY
High density standard hardboard sheet to AS/NZS 1859.4.

2.3 HIGH MOISTURE RESISTANCE UNDERLAY
HMR melamine-urea formaldehyde resin bonded particle board to AS/NZS 1860.1.

2.4 FOAM UNDERLAY
2 mm thick, closed cell foam underlay to provide a moisture membrane. 

2.5 ACOUSTIC UNDERLAY
Minimal thickness sound control system to isolate impact noise. 

2.6 KAHRS PREFINISHED TIMBER FLOORING
Refer to 4. SCHEDULES

2.7 TIMBER TRIM
Skirting, edge strip, reducer strip and nosing as detailed and to match overlay flooring.

Accessories

2.8 FOAM UNDERLAY TAPE
Moisture resistant tape, 48 mm wide.

2.9 CONCRETE SEALER
Two part water based epoxy coating.

2.10 ADHESIVE, DIRECT STICK
Fosroc Jaws adhesive

2.11 ADHESIVE, FLOATING
Kährs ULP adhesive.

Finishes.

2.12 POLYURETHANE
Kährs UV cured acrylic-based lacquer.

2.13 OIL
Kährs oil.


3. EXECUTION

Conditions

3.1 STORAGE AND HANDLING
Accept cartons and packs of timber and accessories undamaged and dry. Store on level, dry surfaces in non-traffic, non-work areas that are enclosed and dry. Avoid damage to cartons and packs of timber. Do not use damaged timber.

3.2 CHECK TIMBER
Check that the timber supplied is as specified. Check the moisture content of the timber to ensure it is at the required level for the installation environment.

Check flooring to ensure it has been supplied at the moisture content recommended by Kährs for the proposed location. Do not remove flooring from packs until just prior to installation.

3.3 DO NOT START
Do not start laying before the building is enclosed, doors are hung and lockable, wet work complete, full lighting available and in the case of air-conditioned buildings the air-conditioning operating for 6 weeks.

3.4 INSPECT THE SUBSTRATE
Inspect the substrate to ensure it provides a suitable finish. Do not start laying if the substrate will not allow work of the required standard.

3.5 STARTING WORK
Starting work means the floor layer accepts the substrate as allowing work of the required standard.

3.6 KAHRS REQUIREMENTS
Carry out the work to conform with this specification and in accordance with Kährs technical requirements.

3.7 TECHNIQUE DISCUSSION
Before beginning the installation, confirm the proposed layout of the timber, grain direction, any other visual considerations of the finished work and specified expansion requirements relating to the specified product.

3.8 SURFACE TOLERANCES, GLUE DOWN
Substrate to have no deviations greater than 3 mm over a 3 metre straightedge in any given direction and no abrupt variations greater than 1 mm over 250 mm.

3.9 SURFACE TOLERANCES, FLOATING
Substrate to have no deviations greater than 5 mm over a 3 metre straightedge in any given direction and no abrupt variations greater than 2 mm over 250 mm.

3.10 MOISTURE CONTENT, TIMBER SUBSTRATE
Check for moisture content and do not commence installation until readings for the whole area show a moisture content of:
- air conditioned buildings: 8 - 12%
- intermittently heated buildings: 10 - 14%
- unheated buildings: 12 - 16%

3.11 MOISTURE CONCRETE, NEW CONCRETE
Clear substrate of debris, clean off surface contamination and carry out surface repairs using a proprietary leveling compound. Carefully feather out at perimeters of repaired areas. Grind level, then vacuum to remove dust. Check for moisture content by hygrometer to BRANZ Bulletin 330. Do not commence installation until the hygrometer readings show 75% or less. Refer to allowable surface tolerances.

3.12 MOISTURE CONTENT, EXISTING CONCRETE, DIRECT STICK
Strip off existing floor coverings. Check for moisture content by hygrometer to BRANZ Bulletin 330. Do not commence installation until the hygrometer readings show 75% or less. Refer to allowable surface tolerances.
 

Conditions - floor heating

3.13 UNDERFLOOR HEATING, FLOATING APPLICATIONS
If a moisture test has not been carried out, turn off the underfloor heating 1 week prior to the test. Check for moisture content by hygrometer to BRANZ Bulletin 330. Do not commence installation until hygrometer readings show 75% or less.
Turn off underfloor heating 48 hours before commencing laying. Wait 48 hours after laying is complete before turning on the underfloor heating. Allow the temperature to build up at a rate of one degree C per day to a maximum of 27 degrees C.
Ensure the thermostat is fitted with a maximum temperature of 27 degrees C.

3.14 ON-FLOOR HEATING, FLOATING APPLICATIONS
Check with the supplier of the on-floor heating. Floating installations may be installed directly over cables and elements when approved in writing by the on-floor heating and flooring suppliers.

Application - surface preparation

3.15 SEAL CONCRETE
Apply concrete sealer before commencing flooring installation.

3.16 EXISTING CONCRETE, FLOATING

3.17 PREPARATION, NEW PLYWOOD OR PARTICLE BOARD, DIRECT STICK
Clear substrate of debris, machine sand to remove surface contamination, then vacuum to remove dust. Refer to allowable surface tolerances.

3.18 PREPARATION, NEW PLYWOOD OR PARTICLE BOARD, FLOATING
Clear substrate of debris, machine sand to make level. Refer to allowable surface tolerances

3.19 PREPARATION, EXISTING TONGUE AND GROOVE, DIRECT STICK
Clear substrate of debris, re-nail or replace any loose or missing boards, then machine stand to make level. Refer to allowable surface tolerances.

3.20 PREPARATION, EXISTING TONGUE AND GROOVE, FLOATING
Clear substrate of debris, re-nail or replace any loose or missing boards, then machine sand to make level. Refer to allowable surface tolerances.

Application - floor underlays

3.21 INSTALLING PLYWOOD UNDERLAYS
Lay plywood sheets with joints staggered, with a 1 mm gap between sheets and 2 mm at perimeters. Use 18 mm divergent staples at 100 mm centres throughout the whole sheet and 30 mm apart, 18 mm in from the edges of the sheets. Punch staples below the surface and sand joints level.

3.22 INSTALLING HARDBOARD UNDERLAYS
Lay standard hardboard, with joints staggered, with a 1 mm gap between sheets and 2 mm at perimeters. Use 18 mm divergent staples at 100 mm centres throughout the whole sheet, 30 mm apart, 18 mm in from the edges of the sheets. Punch staples below the surface and sand joints level.

3.23 ACOUSTIC UNDERLAY
Place acoustic underlay strip around the base of walls, columns and any vertical fixtures. Glue fix underlay pads to substrate using adhesive as required by the underlay manufacturer, ensuring pads are placed diagonally to the joints in the surface floor coverings.

Application - installation

3.24 LAYING, DIRECT STICK
Apply adhesive at the required spread rate. Follow requirements for open time, taking note of substrate porosity, ambient temperature and relative humidity. Remove excess adhesive as the work proceeds using approved techniques. Install the flooring strictly in accordance with Kährs stated requirements. Ensure the required expansion gap is left at perimeters and around fixed obstacles.

3.25 LAYING, FLOATING
Install 2 mm foam underlay to the total floor area, in long, continuous runs, allowing to cove up walls by 50 mm. Tape joints using moisture resistant tape, to create an impervious membrane. Install the timber floor strictly in accordance with the flooring supplier's stated requirements. Ensure the required expansion gap is left at perimeters and around fixed obstacles. 

3.26 LAYING, STAIRCASES AND LANDINGS
Check for moisture content and suitability of substrate prior to installation. Adhesive fix flooring to stair treads, risers and landings.

3.27 EXPANSION GAPS, PERIMETERS
Calculate expansion gaps strictly in accordance with Kährs stated requirements, to suit the environment, size of the installation and product type.

3.28 EXPANSION JOINTS
Cover expansion joints using matching expansion joint covers.

Finishing

3.29 POLYURETHANE, UNFINISHED FLOORING
After installation apply a three coat moisture cured polyurethane system to unfinished solid wood flooring.

3.30 POLYURETHANE, FACTORY PREFINISHED COATED FLOORING
After installation apply a single coat moisture cured polyurethane system to wet areas and en suites.

3.31 OIL, FACTORY PREFINISHED COATED FLOORING
After installation apply one extra coat of Kahrs oil to factory oil prefinished flooring.

3.32 CLEAN
Leave timber flooring surfaces free of adhesive, dirt and debris. Vacuum off, damp mop with a low-foam neutral detergent and allow to dry. Use Kahrs cleaning products. Do not wet the floor or use abrasive cleaners or wax shines. 

Completion

3.33 PROTECT FINISHED SURFACE
Ensure that the completed surface is not used for traffic until curing is complete. Continue to protect the surface until completion of the contract works.

3.34 REPLACE
Replace damaged or marked elements.

3.35 REMOVE
Remove debris, unused materials and elements from the site.

3.36 LEAVE
Leave work to the standard required by following procedures.

4. SCHEDULES

4.1 CONSTRUCTION PLY UNDERLAY
Grade/type: CpD
Thickness: 17 mm

4.2 HARDBOARD UNDERLAY
Thickness: 6 mm

4.3 HIGH MOISTURE RESISTANCE UNDERLAY
Thickness: 12 mm

4.4 ACOUSTIC UNDERLAY
Manufacturer: Pilon
Type: Maxilon PSA

4.5 KAHRS LAMINATED STRIP FLOORING, LACQUER PREFINISHED
Species: ~
Pattern/design: ~
Thickness: 15 mm
Off site factory finish: Factory applied UV cured acrylic based lacquer
On site finish: 1 coat of moisture cured polyurethane to wet areas an en suites
Moisture content: 7 - 8%

4.6 KAHRS LAMINATED STRIP FLOORING, OIL PREFINISHED
Species: ~
Pattern/design: 2 Strip
Thickness: 15 mm
Off site finish: Factory applied oil system
On site finish: 1 coat of Kahrs oil.
Moisture content: 7 - 8%

4.7 KAHRS LINNEA LAMINATED STRIP FLOORING, LACQUER PREFINISHED
Species: ~
Pattern/design: 2 Strip
Thickness: 7 mm
Off site finish: Factory applied UV cured acrylic based lacquer
On site finish: 1 coat of moisture cured polyurethane to wet areas an en suites.
Moisture content: 7 - 8%

4.8 KAHRS LINNEA LAMINATED STRIP FLOORING, OIL PREFINISHED
Species: ~
Pattern/design: 2 Strip
Thickness: 7 mm
Off site finish: Factory applied oil system
On site finish: 1 coat of Kahrs oil.
Moisture content: 7 - 8%

4.9 WOOD BLOCK PARQUET
Species: ~
Pattern: ~
Size: ~ mm x ~ mm
Thickness: 20 mm
Finish: ~

4.10 WOOD MOSAIC PARQUET
Species: ~
Pattern: ~
Size: ~ mm x ~ mm
Thickness: 8 mm
Finish: ~

4.11 STRIP FLOORING
Species: ~
Size: ~ mm x ~ mm
Thickness: ~ mm
Finish: ~
Moisture content: ~