durability - hazards
DESCRIPTION
Durability - Hazards. Biological/ Physical Hazards. TIMBER. Species Natural durability of heartwood. Weathering Fire Chemical. Design Detailing minimises exposure to hazards. Treatment enhances durability of sapwood. Fungi Termites / borers Marine. Maintenance ensures - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/1.jpg)
Durability - Hazards
Biological/ PhysicalHazards
WeatheringFireChemical
TIMBERSpeciesNatural durability of heartwood
Maintenance ensures protection remains functional
Treatmentenhances durability
of sapwood
FungiTermites / borersMarine
Design Detailingminimisesexposure
to hazards
![Page 2: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/2.jpg)
Hazards Anything that may cause deterioration of timber
during service Reduce long-term performance Can counter the effects of hazards by
• Selection of appropriate species (Natural Durability)• Treatment• Detailing to minimize exposure to hazards
Includes weathering, chemicals, fire• No classification for these hazards – use appropriate
detailing to minimize hazard impact Includes fungal, insect, marine organism attack
• Can classify according to Hazard Class scale
![Page 3: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/3.jpg)
Physical Hazards Weathering - degradation due to weather
• rain• sunlight
Chemicals - timber performs well relative to steel/concrete• resistant to degradation for pH>2 and pH<10• softwoods marginally better than hardwoods
Fire - burning• strength during fire• insulation of walls• prevention of spread
![Page 4: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/4.jpg)
Preventable problems
Weathering
Kangaroo Point, QldPhoto: Geoff Boughton
Plamerston, NTPhoto: Geoff Boughton
Marmion, WAPhoto: Geoff BoughtonPhoto: Geoff Boughton
![Page 5: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/5.jpg)
Biological Hazards
Fungi Termite/borers Marine organisms
Can classify according to Hazard Class scale
![Page 6: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/6.jpg)
Preventable problems
Fungi damage
Marine borer damageTermite damage
Photo: Geoff Boughton
Photo: Geoff Boughton Photo: Geoff Boughton
Horticultural Training Centre, Mornington, Tas
Photo: Greg Nolan
![Page 7: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/7.jpg)
Hazard ClassHazard Class
Exposure Service Conditions Biological Hazard
H1 Inside above ground Fully protectedWell ventilated
Borers only
H2 Inside above ground Protected from wetting, nil leaching
Borers and termites
H3 Outside above ground Moderate wetting & leaching Decay borers and termites
H4 Outside in ground Severe wetting & leaching Severe decay borers and termites
H5 Ground contact Extreme wetting, leaching &/or critical use
Very severe decay borers and termites
H6 Marine waters north & south
Prolonged immersion in sea water
Marine wood borers and decay
H6SW Marine waters south only
Prolonged immersion in sea water
Marine wood borers and decay
![Page 8: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/8.jpg)
Natural Durability (Heartwood)Extractives and growth characteristics
affect natural durability of timber species
Class Durability Species
1 Highly durable Ironbark, Tallowwood, Cypress, Turpentine, Forest red gum
2 Durable Spotted gum, Blackbutt, River red gum, Western Cedar, Stringybark (yellow & white)
3 Moderately durable
Brush box, Rose/flooded gum, Sydney blue gum, Silver topped stringy bark
4 Non-durable Douglas fir, Hoop pine, Radiata pine, Mountain ash/ Tasmanian oak, Unidentified timbers
![Page 9: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/9.jpg)
Long-term Performance of Timber
Can match natural durability class with environmental hazard to estimate long-term performance of untreated timber heartwood
Natural Durability
Class
Heartwood Service Life
(years)
Heartwood Service Life
(years)
Heartwood Service Life
(years)H1
fully protectedH3
Above ground exposed
H5 in-ground
Class 1 50 + 50 + 25 +
Class 2 50 + 30 15 – 25
Class 3 50 + 15 8 – 15
Class 4 50 + 5 - 8 < 5
![Page 10: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/10.jpg)
Hazard links to Treatment levelTreatment levels have classes with same names as the
Hazard levels• H1 – lowest level treatment – suitable for H1 hazard
environments – indoors, protected• H2 – treated timber suitable for H2 hazard environments –
suitable for all internal use• H3 – treated timber suitable for H3 hazard environments –
suitable for above ground external use• H4 – treated timber suitable for H4 hazard environments –
suitable for use in contact with dry ground• H5 – treated timber suitable for H5 hazard environments –
suitable for all in-ground use
![Page 11: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/11.jpg)
H1indoors, protected, ventilated
Aged Care residence, Tapping, WA
Photo: Geoff Boughton
Wall panels Holybank Forest Centre Lilydale, TasPhoto: Greg Nolan
![Page 12: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/12.jpg)
H2all internal use, poorly ventilated
eg. concealed wall frames and floor timbers
![Page 13: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/13.jpg)
H3above ground external use
Marina residence, SA Photo: Greg Nolan
Queenscliffe Jetty, Vic. Photo: Greg Nolan
![Page 14: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/14.jpg)
H4in contact with dry ground
Play equipment, Geelong, VicPhoto: Geoff Boughton
Hardwood walkway, Margaret River, WA
Photo: Geoff Boughton
![Page 15: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/15.jpg)
H5all in-ground use, critical, subject to wetting
pole house, Townsville, QldPhoto: Geoff Boughton
Nanga Camp, Dwellingup, WAPhoto: Geoff Boughton
Logging bridge, Pemberton, WAPhoto: Geoff Boughton
![Page 16: Durability - Hazards](https://reader036.vdocument.in/reader036/viewer/2022062410/56815bde550346895dc9cd17/html5/thumbnails/16.jpg)
H6Marine use – prolonged immersion in sea water
Bussleton Jetty, WAPhoto: Geoff Boughton
Bussleton Jetty, WAPhoto: Geoff Boughton