Timber Species Thermally Modified Pine

Pinus radiata

Thermally Modified Pine

Also known as: Thermally Modified Pine, TMT Pine

Region of Origin: New Zealand
CladdingExterior ScreeningFascia & Trim BoardsLandscaping Features
Density
420-450 kg/m³
Durability
Durable
Janka
3.0-3.5 kN
Strength Group
Modified Softwood
Thermally Modified Pine timber grainTimber Grain

About this Timber

General Description

Thermally Modified Pine is manufactured from thermally modified New Zealand plantation Radiata Pine, supplied in solid, flat-sawn boards. It is processed in computer-controlled kilns at or above 230�C, using steam to modify the wood all the way through.

Thermally Modified Pine offers an environmentally responsible alternative to native or chemically-treated timbers for cladding, screening and exterior appearance applications.

Working Properties

How This Timber Works

Lightweight and stable, with variable grain and texture typical of crown cut timber. Machines cleanly with sharp tools, finishes well, and is suited to applications where improved dimensional stability is required.

Mechanical Properties

Janka hardness is approximately 3.0 to 3.5 kN, with modulus of rupture reduced compared with unmodified pine due to the thermal modification process. Modulus of elasticity is moderate and generally comparable to radiata pine, though slightly reduced. Crushing strength is considered moderate. Not intended for structural load-bearing use.

Technical Data

Technical Specifications

Density
420-450kg/m³
Air dry density (avg)
Durability Class
Durable
Strength Group
Modified Softwood
Structural classification
Janka Hardness
3.0-3.5kN
Surface hardness rating
Process
Thermal Modification at 230�C
No chemical preservatives - steam-modified throughout

*Air Dry Density (kg/m³) is an average indication only and actual values may vary. Refer to strength, shrinkage and durability classification tables for full details.

Reference Tables

Timber Classification Tables

Standard NZ classification tables for strength groupings, shrinkage and durability. This species is highlighted in each table.

Minimum Values for Strength Groups
Unseasoned Timber  |  Units: MPa = 145 lb/sq.inch
Strength Group Modulus of Rupture Modulus of Elasticity Max Crushing Strength
S1 103 16300 52
S2 76 14200 43
S3 73 12400 36
S4 62 10700 31
S5 52 9100 26
S6 43 7900 22
S7 36 6900 18
Minimum Values for Strength Groups
Seasoned Timber  |  Units: MPa = 145 lb/sq.inch
Strength Group Modulus of Rupture Modulus of Elasticity Max Crushing Strength
SD1 150 21500 80
SD2 130 18500 70
SD3 110 16000 61
SD4 94 14000 54
SD5 78 12500 47
SD6 65 10500 41
SD7 55 9100 36
SD8 45 7900 30
Shrinkage Classifications
Shrinkage from Green to Oven-dry (12% MC) – % before reconditioning
Description of Shrinkage Tangential Radial
Very Low0 – 3.50 – 2
Low3.5 – 5.02 – 3
Medium5.0 – 6.53 – 4
High6.5 – 8.04 – 5
Very High> 8.0> 5
Durability Classifications
Approximate service life (years)
Grade of Durability Fully Protected Above Ground, Exposed In-Ground, Exposed
Very Durable> 50> 40> 25
Durable> 5015 – 4015 – 25
Moderately Durable> 507 – 155 – 15
Non-Durable> 500 – 70 – 5
This species – Strength Group
SD8
Highlighted in the strength tables above
This species – Durability
Durable
Highlighted in the durability table above

Applications

Main Uses

Cladding Exterior Screening Fascia & Trim Boards Landscaping Features

Stock & Sizes

Availability

Stocked in New Zealand in exterior cladding and screening profiles designed for residential and commercial projects.

Quality Standard

Grading

Grade Clears