Selection & Specification Guide · 2020-06-25 · al wood products above ground such as deck-ing, bearers and joists, and similar for H3 as per AS1604.1. H4 – for non-structural

Selection & Specification Guide

Preservative Treatments for

Timber & Wood Products in New Zealand

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Tanalised® Wood Products

The Case for Built-In Durability

Wood is a versatile construction material that has many benefits over alternative materials with regard to net environmental impact, cost effectiveness and ease of use. It is the only significant building material whose production and use can result in a net positive carbon storage balance as the wood fibre is created by photosynthesis where growing trees absorb atmospheric carbon dioxide.

Managed plantation forestry is the most sustainable way to produce wood fibre for manufacture of timber and wood products. New Zealand has a strong plantation forestry sector mainly utilis-ing exotic species such as Radiata pine among others. New Zealand also has a modern and efficient wood processing industry to convert this plentiful resource into a wide range of useful building and other products for domestic and export markets.

Durability and reliability in service are the key considerations in determining the suitability of building materials along with good design and construction practices to ensure a resilient and sustainable built environment. In many applications timber and wood products require protection from natural biological agents such as mould, decay and insects. The best way of ensuring the durability of timber and wood products is by industrial pre-treatment incorporating a Lonza pre-servative in accordance with New Zealand, Australian or other recognised standards. Lonza works with leading wood processors and manufacturers in New Zealand and around the world to improve the durability and serviceability of wood products using our chemical and related tech-nologies.

Tanalised® has been the traditional treatment brand in New Zealand for hardworking rural and outdoor wood products since the 1940’s. These days there are many more protection options available from Lonza for the current generation of wood products. Lonza and our customers take pride in ensuring that treated wood and timber products incorporating our chemistry are pro-duced in environmentally compliant facilities, safe to use, fit for purpose and supplied in con-formance with relevant standards.

We hope that you find this guide useful and please feel free contact us for additional information.

Purpose

This document is designed to assist producers, resellers, specifiers and end-users of preserva-

tive treated wood products to better understand the appropriate application of industrial wood

preservatives for various types of wood products and correct selection and specification of pre-

servative treatment for various end-use situations. Industrial wood preservatives from Lonza are

only for use in suitably constructed and authorized industrial wood treatment facilities and are not

available for use by consumers or the end-user.

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Framebor® N is a H1.2 boron based framing

treatment solution using a novel patented bo-

ron formulation which provides significant pro-

cessing improvements compared to most oth-

er boron preservatives.

Our boron formulation and treatment process

results in a minimal moisture content increase

in the treated timber. Because the solution has

a lower conductivity and is less hygroscopic

than some borate formulations, moisture con-

tent readings with conductivity meters is closer

to true MC%. To keep the wood clean during

pre-construction it also incorporates an effec-

tive mouldicide. Ideal for treatment of kiln dried

stress graded timber with low uptake Lowry or

Reuping type treatment processes.

Framebor® N wood preservative is applied

with proprietary pressure and vacuum impreg-

nation processes developed by Lonza to en-

sure that the NZS3640 H1.2 requirements for

preservative penetration and retention are

met.

Uses: H1.2 as per NZS3640 - all interior tim-

ber construction where not directly exposed to

weather —wall framing, sub-floor framing, roof

framing. See NZS3602 for further details.

Timber species: Radiata pine, New Zealand

Douglas fir. Other timber species may be ap-

proved on testing and verification.

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Boron-based Preservatives

Fasteners: The Framebor® treatment itself is

not corrosive to steel. Normal bright steel nails

and connectors are suitable.

H1.2 treatments normally incorporate a red or

pink colouring dye for easy identification of the

treated wood.

Painting: H1.2 treated timber is not normally

painted. If painting is required, use of a stain

blocking primer is recommended to prevent

bleed through of the red colouring dye.

Pre-construction exposure: Boron based

preservatives are not fixed in the timber and

can be leached out under long term exposure

to rain or ground contact. Exposure to weather

prior to and during construction should be min-

imized (<3 months) to ensure compliance with

treatment requirements in the finished struc-

ture. Do not store the timber directly on the

ground. If H1.2 treated timber is exposed for

more than 3 months re-testing of affected sec-

tions may be required by the relevant territorial

authority to ensure that the timber is still com-

pliant.

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Diagrams used courtesy of the Ministry of Busi-

ness, Innovation and Employment. See Building

Code Compliance Document B2 Durability for full

details.

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Specified treatments for timber framing

(Radiata pine or Douglas fir) as per the

New Zealand Building Code.

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Diffusol® is a traditional boron based preserva-

tive intended for application to sawn timber by

pressure treatment or dip diffusion to meet

NZS3640 requirements for hazard class H1.2.

Diffusol® wood preservative may also be used

to treat hardwood timbers to hazard class H1

under AS1604.1. for immunization against

beetle borers. Contact Lonza for further de-

tails.

Uses: H1.2 as per NZS340 - all interior timber

construction where not directly exposed to

weather —wall framing, sub-floor framing, roof

framing. See NZS3602 for further details.

H1 as per AS1604.1 – lyctus borer immuniza-

tion of susceptible hardwoods

Engineered Wood Products

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With the acquisition of Zelam, Lonza is now

able to offer glue line additive treatments

(GLA) for engineered wood products such as

LVL (laminated veneer lumber) and plywood.

GLA treatments have the advantage of incor-

porating the preservatives directly in the glue

used to bond the wood veneers and hence

ensures that the treatment is incorporated in

the wood product from the inside out, not

from the outside in as with conventional treat-

ment.

Timber species: Radiata pine, New Zealand

Douglas fir. Lyctus susceptible hardwoods

such as certain eucalyptus species and

shorea spp (Meranti).

Fasteners: The Diffusol® treatment itself is

not corrosive to steel. Normal bright steel

nails and connectors are suitable

Diffusol® wood preservative can be applied

with dip, spray or pressure treatment process-

es. Lonza can advise on the details of the

various treatment processes and solution

concentrations appropriate for different types

of wood commodities.

Azotek® is the latest addition to this product

family and uses state of the art chemical tech-

nology to provide highly effective protection

against decay fungi and insects to LVL and

related products for use in H1.2 application in

New Zealand. LVL is an important innovation

for New Zealand building offering high

strength and reliable engineering properties

for critical load and large span applications –

and now with the security of Azotek® protec-

tion against decay and insects.

CCA stands for copper, chrome arsenate and

this remarkable wood preservative has been

in use for over 50 years. It has stood the test

of time and even today is still preferred where

timber and wood products require the highest

levels of protection and reliability in demand-

ing situations. CCA wood preservative is still

the longest serving and most widely used

timber treatment in New Zealand, Australia

and many other parts of the world. Even in

cases where CCA preservative has been

withdrawn from some residential applications,

it is often retained for utility, structural and

rural uses where the maximum durability and

engineering safety is essential.

Uses: The unique properties of Tanalith®

CCA preservative make it the ideal choice

where treated wood products must serve in

demanding structural, ground contact or water

contact applications.

H3.2 as per NZ3640 for protection of structur-

al wood products above ground such as deck-

ing, bearers and joists, and similar for H3 as

per AS1604.1.

H4 – for non-structural or non-critical wood

products in ground contact such as fence

posts, garden edges, landscaping sleepers et

cetera.

H5 – critical or structural timber components

in ground or fresh water contact such as

house piles, utility poles and engineered earth

retaining structures.

H6 – marine or brackish water contact such

as wharf piles and similar structures in perma-

nent salt water contact. Note that H6 specifi-

cation for New Zealand application is not

transferable to Australia or other countries.

Timber Species: Tanalith® CCA preservative

is suitable for treatment of common softwood

and hardwood timber products.

Moisture content: Immediately after treat-

ment, CCA treated timber will have a high

moisture content. For H3.2 uses, it should be

specified if the timber is to be supplied wet

after treatment or re-dried (moisture content <

21%).

Fasteners: CCA preservative treatments may

be slightly to mildly corrosive to steel and

other metals in contact with the treated tim-

ber. Galvanized steel or other corrosion

Copper-based Preservatives �

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resistant fasteners are recommended for all

weather exposed or ground contact situations.

Stainless steel fasteners and connectors (or

other metals of high corrosion resistance)

should be used for critical applications where

very long service life is required or where ad-

ditional sources of corrosion are present, such

as salt. The treated wood should not be in-

stalled in direct contact with zinc-alum sheet

roofing as corrosion may result. Use of pre-

painted sheet metal roofing is recommended

and installation of a durable water resistant

membrane between the materials.

Disposal: Tanalith® CCA treated timber off-

cuts and redundant pieces are not a hazard-

ous waste. However it is recommended that

care is taken to dispose of this waste properly

(as a solid waste). It should not be mixed with

green waste for composting and MUST NOT

be used as home heating or cooking fuel as

toxic fumes or residues may be produced.

Use restrictions: The Environmental Risk

Management Authority of New Zealand

(ERMANZ now EPANZ) conducted a review

of CCA preservative in 2003 with extensive

reference to overseas practice and regula-

tions as well as experience of use in New

Zealand. They determined that there was no

specific information indicating that CCA treat-

ed wood posed unacceptable risks for users

and the community in New Zealand where

used as recommended and that no re-

strictions on its use was justified at the time.

However some overseas countries may have

restrictions on the import or use of CCA treat-

ed wood products. Contact Lonza for further

details.

Copper-based Preservatives cont...

Lonza offer a range of copper based preserv-atives for protection of wood and timber prod-ucts in general outdoor and ground contact use. These are environmentally advanced timber preservatives that incorporate copper in combination with azole or quaternary am-monium compound co-biocide wood protec-tion system. The Tanalith® copper based preservatives conform to the latest Unites States EPA, European Union and Australian directives regarding suitable wood preserva-tive products for residential and close human contact use. Copper based preservatives are in wide use around the world including many countries in Europe, the United States and more specifically Japan, New Zealand, Aus-tralia in the Asia Pacific region.

Uses: Tanalith® copper based preservatives are ideal for common above ground (H3 / H3.2) and ground contact (H4, H5) applica-tions that require robust levels of protection but where there may be sensitivity to arsenic or chromium containing preservatives. Exam-ples are outdoor and garden furniture, deck-ing, playground equipment, hand rails and landscaping in schools, public facilities or other areas where high levels of direct human contact are expected.

Timber Species: Tanalith® E and Tanalith® Q preservatives are suitable for treatment of most common softwood and hardwood timbers. Being a dispersion (or suspension) product, Tanalith Eµ preservative is �

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Product Formulation

Tanalith® E preservative

Copper as a solution with azole co-biocide

Tanalith® Eµ preservative

Copper as a micronised dispersion with azole co-biocide

Tanalith® Q preservative

Copper as a solution with quaternary ammonium co-biocide

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recommended for Radiata pine and similar

softwoods only#��

Moisture content: Immediately after treat-ment, the treated timber will have high mois-ture content. For H3.2 uses, it should be specified if the timber is to be supplied wet after treatment or re-dried (moisture content < 21%).

Fasteners: Tanalith® copper based preserva-tive treatments may be slightly to mildly corro-sive to steel and other metals in contact with the treated timber. Galvanized steel or other corrosion resistant fasteners are recommend-ed for all weather exposed or ground contact situations. Stainless steel fasteners and con-nectors (or other metals of high corrosion resistance) should be used for critical applica-tions where very long service life is required or where additional sources of corrosion are present, such as salt. The treated wood should not be installed in direct contact with zinc-alum sheet roofing as corrosion may result. Use of pre-painted roofing is recom-mended and install a durable water resistant membrane between the materials.

Painting: All Tanalith® treated timber (CCA and copper based) can be painted like normal timber once dry and clean. Painting or stain-ing of dimensioned timber in exterior, weather exposed situations is strongly recommended to minimize surface mould, checking, sun bleaching and dimensional movement.

VACSOL® AZURE is a new generation LOSP

(Light Organic Solvent Preservative) treatment

incorporating all carbon based and biode-

gradable triazole and synthetic pyrethroid ac-

tive constituents. Vacsol® Azure wood pre-

servative provides effective protection against

fungal decay and insect attack for above

ground building applications. The key benefit

of LOSP treatment is that it causes no change

in the moisture content or dimensions of the

wood products. Vacsol® Azure preservative is

ideal for protection of high value appearance

and engineered wood products treated in final

shape and form. Typical examples are exteri-

or joinery and mouldings, finger jointed and

laminated timber products and engineered

wood products.

Uses: H3.1 as per NZS3640 – protection of

non-structural wood products exposed to the

weather and which are fully painted. Note that

H3.1 LOSP treatment cannot be substituted

for H1.2 treatment in timber framing for New

Zealand.

Australia - H3 as per AS1604.1 for protection

of general structural and non-structural wood

products above ground.

Timber Species: Radiata pine

Plywood & LVL: Due to the nature of plywood

and LVL it is recommended that additional

conditioning time is allowed for depending

upon drying conditions, the types and thick-

ness of plywood or LVL treated and the

amount of preservative absorbed during treat-

ment.

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Azole-based Preservatives

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Painting: For New Zealand, most H3.1 treat-

ed timber products are supplied with a factory

applied primer coating. All H3.1 treated timber

products should be fully painted where ex-

posed to weather. Timber treated with Vacsol®

Azure preservative is ideal for painting or

staining providing that a few precautions are

taken. Most importantly the timber must be

conditioned for at least 7 days after treatment

before painting to ensure that any excess sol-

vent has flashed off.

In industrial production facilities applying pre-

primer this time may be accelerated by forced

air drying, vacuum drying or other means.

Fasteners: Vacsol® Azure treatment is not

corrosive to steel or other common metals so

no deviation from normal practice is called for.

However corrosion resistant fasteners are

recommended for all exterior or weather ex-

posed timber work.

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Vacsol® Aqua PT is a waterborne, multi-

functional wood preservative system for timber

used above ground containing fungicides

(propiconazole & tebuconazole), insecticides/

termiticides (permethrin and/or imidacloprid)

with optional anti-mould additives and water

repellent agents.

Uses: Under AS1604.1 Vacsol® Aqua PT

treated timber can be used for general out-

door, exposed, above ground situations includ-

ing decking, bearers and joists, fascia, weath-

erboards, plywood cladding, door and window

surrounds, hand rails, laminated posts and

beams, etc. In New Zealand, outdoor uses

include H3.1 which are fully painted and for

non-structural application such as cladding,

fascia and reveals. Section B2 Durability of the

NZ Building Code allows water borne azole

treatment for H1.2 (framing).

Treatment of timber products destined for the

US market can be deemed equivalent to AW-

PA UC3A requirements (close to NZ H3.1) and

possibly UC3B in some cases. Consult Lonza

for further details.

Timber Species: The Vacsol® Aqua PT treat-

ment is intended for kiln dried timber such as

Radiata pine in a conventional vacuum-

pressure plant. Consult with Lonza regarding

the treatment of other timber species.

Azole-based Preservatives cont... �

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Timber to be treated should be kiln dried to

less than 20% moisture content (<16% pref-

erable), be in final shape and form with all

machining completed before treatment and

be free from decay, mould, insect attack and

sapstain. Lonza will advise on the most ap-

propriate treatment schedule for the com-

modities being treated and specifications to

be met. After treatment, timber should be

allowed to air-dry in a well-ventilated area for

at least 48 hours before wrapping or further

processing.

Painting, Gluing & Fixings: Timber treated

with Vacsol® Aqua PT preservative can be

painted with alkyd or acrylic based paints

once dry. All normal wood glues are compati-

ble subject to checking moisture content.

The treated timber is not corrosive to steel,

aluminium or copper alloy fixings. However

corrosion resistant fixings (galvanized steel

as a minimum) is recommended for all timber

in exterior applications.

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Moisture content: Structurally graded timber

(Radiata pine) should be supplied with mois-

ture content less than 21%. Most general out-

door and ground contact treated wood prod-

ucts will be supplied wet (moisture content >

21%). Contact your wood supplier for details.

Reworking after treatment: Treated wood

and timber products should not be re-sawn or

re-sized after treatment by end users (except

for cutting to length or notching as required for

fitting and joining). These processes may re-

duce the protection afforded by the treatment.

Where timber is cut or rebated in H3, H4 and

H5 situations, the exposed area should be

resealed with a suitable ‘in-can’ protective such

as Tanalised® Enseal to ensure that an integral

protection envelope is maintained. In H4 situa-

tions it is recommended not to place a cut end

in ground contact. For H5 applications a cut

end must not be placed in ground or water

contact. No cutting or notching should be done

after treatment on H6 level treated timber in

the water contact zone.

Painting: Painting improves the appearance

and dimensional stability of treated wood and

timber products. It is strongly recommended

that all finished and sawn timber in weather

exposed applications is painted, stained or

sealed to reduce surface deterioration, check-

ing or dimensional movement. Treated timber

can be painted or stained like normal untreated

timber providing that it is dry and clean. Al-

ways follow the paint manufacturer’s instruc-

tions.

Nails, bolts, fixings and metal in contact

with wood: Corrosion resistant fasteners, fix-

ings and connectors should be used for all

timbers in weather exposed, damp or ground

contact applications. See details under each

preservative summary.

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Additional Application Notes

Identification and branding: Tanalised® pro-

tection cannot be applied by the end user or on

site. A conforming Tanalised treatment can only

be provided by pre-treatment in dedicated indus-

trial facilities. All treated wood and timber prod-

ucts should carry a treatment brand that identi-

fies the treatment or hazard level to which the

product has been treated, the preservative used

and the identity of the treatment provider as

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Suitable Applications:

The range of Lonza wood protection products

covers applications in all the hazard levels listed

in NZS3640:2003. It is important to understand

that treated timber and wood products must not

be used in a situation at a higher hazard level

than that for which it was branded. For example,

timber branded for H3.2 application should not

be used in ground contact (H4), and timber

branded H4 is not to be used in an H5 applica-

tion. Note that New Zealand treatment specifica-

tions do not necessarily align 100% with stand-

ards or requirements in other jurisdictions. It is

strongly recommended that specialist advice is

sought prior to specifying treatment for export

markets.

Safety & Environmental Protection

Wood preservatives are generally restricted use

products and require appropriately trained opera-

tors to use and handle the chemicals (Approved

Handlers). Wood preservatives are required to

be registered with the New Zealand Environmen-

tal Protection Authority. Safety Data Sheets

(SDS) and other safe handling information re-

sources are available from Lonza.

Wood preservative processing is a notifiable

activity requiring appropriate trade or site use

consents. Industrial timber treatment plant facili-

ties are required to conform to strict environmen-

tal regulations and are under the jurisdiction of

environmental protection and / or regional au-

thorities.

Treated wood and timber products are safe to

use however as with handling many materials,

certain precautions should be observed, particu-

larly where machining or sanding generates

wood dust and air borne residues. Keep work

areas clean, avoid accumulation or inhalation of

wood dust and wash hands after handling the

materials.

Treated wood wastes and off cuts are generally

not considered to be a hazardous waste. How-

ever, care should be taken to dispose of this

waste appropriately through normal disposal

services. Treated timber wastes should not be

mixed with general green waste for composting.

Treated timber should not be burnt in uncon-

trolled situations such as for cooking or home

heating.

Further Information

For further sources of information contact the NZ

Timber Preservation Council. This information is

presented in good faith and is believed to be

accurate, based on the best available advice and

knowledge at the time of printing. However due

to the variability of application situations, the user

must satisfy themselves as to the suitability of

the information or the products for any particular

purpose or circumstance or take suitable expert

professional advice.

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NZS 3640 Chemical Preservation of Round and Sawn Timber covers treatment re-quirements for treatment of round and sawn timber.

NZS 3602 Timber and Wood-based Products for Use in Building

NZS 3604 Timber Framed Buildings

New Zealand

Building Code

Also see Clauses B2 Durability and E2 External Moisture of the New Zea-land Building Code for latest acceptable solutions which may not be reflect-ed in current standards.

AS/NZS 1604.2- 5 AS/NZS 1604 parts 2 to 5 cover requirements for treatment of composite, laminated and veneer based wood products.

RELEVANT STANDARDS

The following are examples of national and joint standards which are directly relevant to preserv-

ative treated wood products. Other standards may apply or be called on by these standards.

HAZARD LEVELS & APPLICATIONS

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Summary of Lonza Wood Preservatives for Key Applications as per NZS3640 Treatment (Hazard) Levels

Hazard

Level

Exposure and

Service Hazards

Specific Application

Examples

Minimum Retention Levels

(see NZS3640 for full de-

tails)

Conforming pre-

servative (and

number (1))

H1.2 Framing and interior

construction timber not

in direct weather expo-

sure (see NZS 3602).

0.40% m/m BAE (2)

0.08% m/m azoles(3)

Framebor® N (11)

Diffusol® (11)

Vacsol® Aqua PT(64)

LVL for H1.2 Triadimefon + cypriconazole(7) Azotek® (66)

H3.1 Outdoors, exposed

to the weather,

above ground

Exterior non-structural

building components,

cladding fascia, joinery

– see NZS3602

0.06% m/m azoles (3)

Vacsol® Azure (64)

Vacsol® Aqua PT

(64)

H3.2 Outdoors, exposed

to the weather,

above ground, or

with a risk of mois-

ture entrapment

All H3.1 uses, plus

outdoor structural appli-

cations and decking –

see NZS3602

0.23% m/m copper + azole (4)

0.35% m/m copper + DDAC (5)

0.37% CCA elements (6)

Tanalith® E (58) or

Tanalith® Eµ (88)

Tanalith® Q (90)

Tanalith® CCA (01)

H4 Exposed to the

weather, in ground

contact

Non-structural or non-

critical timber in ground

contact - fence posts,

landscaping timbers



0.72% m/m CCA elements (6)


Tanalith® Eµ (88)

Tanalith® Q (90)

Tanalith® CCA (01)

H5 Exposed to the

weather, in ground

or fresh water con-

tact

House piles and poles.

Crib walling or other

engineered earth re-

taining structures



0.95% m/m CCA elements (6)


Tanalith® Eµ (88)

Tanalith® Q (90)

Tanalith® CCA (01)

H6 Marine or brackish

water exposure.

Marine borer

hazard

Marine piles, jetty cross

-bracing, landing steps,

sea walls

0.40% m/m copper (as Cu

only)

Tanalith® CCA (01)

Interior, protected

from the weather,

but with the possi-

bility of exposure

to moisture.

(1) Every recognised preservative type has a number assigned for identification. See NZS3640 sections 4

and 5 for details of preservative specifications and identification numbers.

(2) BAE stands for Boric Acid Equivalent (H3BO3).

(3) Azoles as combined retention of propiconazole + tebuconazole. This treatment also includes an insecti-

cide where there is a termite or wood borer hazard.

(4) Azole as tebuconazole alone or as tebuconazole + propiconazole (1:1 ratio)

(5) DDAC is didecyl-dimethyl ammonium chloride or carbonate

(6) The term CCA elements means the total of copper (Cu) plus chromium (Cr) plus arsenic (As) elements.

(7) As glue line additive + face veneer application – see NZS3640.

The information contained herein is believed to be correct and corresponds to the latest state of scientific and technical

knowledge. However no warranty is made, either expressed or implied, regarding its accuracy or the results to be obtained

from the use of such information. Some products may not be available in all markets or for every type of application. Any

user must make their own determination and satisfy themselves that the products supplied by Lonza and the information

and recommendations given by Lonza are (i) suitable for intended process and purpose, (ii) in compliance with environmen-

tal, health and safety regulations, and (iii) will not infringe any third party’s intellectual property rights. © Lonza 2015

All copyrighted material has been reproduced with permission from their respective owners, all other materials ©2016 Lon-

za. Tanalith, Framebor, Vacsol, Diffusol, Azure Aqua, Azotek, Enseal and Tanalised are trademarks of Lonza Group or its

affiliates.

October 2016

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Arch Wood Protection (NZ) Ltd

A Lonza company

265 James Fletcher Drive Otahuhu

Auckland New Zealand

Tel: 09 276 3646 Fax: 09 270 2020

Email: [email protected]

www.lonzawoodprotection.com

Documents

Selection & Specification Guide · 2020-06-25 · al wood products above ground such as deck-ing, bearers and joists, and similar for H3 as per AS1604.1. H4 – for non-structural