Level 0 – Outdoors with unrestrained access by harmful agents

Starting from a situation of no preservation steps taken, this is the base level from which to evaluate the effectiveness of any improvements to block pests. Plan B presents the first steps to reduce the effects of pests in this situation.


Building exterior, totem pole, public sculpture.

Plan B



Outdoors, rural or urban, may be sheltered by trees, buildings, or landforms. May be well or poorly drained. May be windswept or sheltered. Urban sites are likely public spaces. Rural sites may be remote with little visitation.

Plan B

Some environmental modification may be considered if the site is clearly harmful; for example, cutting back encroaching growth that physically disrupts structures, shelters pests, or induces higher moisture content by casting shade; cutting back clinging vines that disfigure, obscure, create a fire risk, etc.


No exterior enclosure; fully exposed to year-round material weathering; object sitting directly on ground.

Plan B

There is considerable preservation justification for moving objects under shelter. If that is not possible, in situ techniques should be considered. Use bird netting or enclosures made of sheet material (metal, tarpaulins) to block pests if the object is open to weather, collecting detritus, or housing animals (in the case of large machinery, derelict buildings). Install angled raincaps (e.g. on pole tops, exposed beam ends) where possible to reduce roosting and bird detritus that induces rot.

Portable fittings


Plan B

Separate rot-prone objects from the soil they are resting on: use compacted gravel; paved surfaces; a fungicide/insecticide-treated wood shoring; a short concrete plinth; or a moisture barrier (such as a sheet metal layer between post and pillar; where the sheet metal protrudes horizontally, bend it downward to avoid conducting splashed water into the joint). Use these solutions to reduce ground contact, slow fungal attack, and reduce burrowing insect access. Metal shields, which divide wood from foundation elements, will force termites to run their shelter tubes across the shield where they are readily detected, or carpenter ants to walk along visible surfaces, which improves detection.


None. Abandoned to fate.

Plan B

Routinely remove grime, soil pockets (which are a site for rapid biological activity), and all surface growths such as lichen, mould, moss,etc. Examine object for insect infestations, especially wood borers. Wood-borer activity can lead to structural collapse. Use residual pesticides or fungicides when warranted. Sealing wood to reduce moisture absorption is most effective when the sealing agent is applied on a smooth surface, or on minimally weathered new wood. Deteriorated surfaces allow easy paths to form that water can then follow into the interior. This condition supports systemic fungal attack. All surface treatments need to be periodically repeated as the surface of the object weathers. Be aware that borate fungicide and insecticide treatments can be washed away from wood surfaces. However, the solid borate rods and chips put into holes bored into timber do rely on wood moisture to migrate further into the wood and confer protection. Preservative fungicides and insecticides may stain surfaces; therefore, test first. Subterranean sections of an object near the surface of the soil can be excavated, approved fungicide applied, and surface drainage improved. The most rapid pest attacks generally occur in the soil just above the water table, where the soil is still oxygenated. Thank people for their contribution when they detect problems and report them to you.


Open to maximum algal, fungal, rodent, and insect attack. Chronic bird and bat roosting. Systemic effects due to pest attacks on the materials they are adapted to use.

Plan B

Reduced algal, fungal, rodent, insect attack, and bird roosting. A range of surface to systemic effects is still expected because the object is exposed to the elements, but the damage has been reduced because of detection and remediation.

Expected deterioration

Noticeable effect or damage in one season, as rapidly as what can happen to a dead tree, mammal, insect, or leaf. Colonization of more resistant items by algae, moss, fungi, and plants in a few years. Anticipated effects show within a few years on robust items, and within a few days on delicate items. Self-sheltered parts of the object will retain features as noted in Level 1, but will eventually succumb to harmful agent attacks.

Plan B

Noticeable effect or damage in one season. Anticipated effects show within a decade on robust items, and within a few days on delicate items. Self-sheltering parts of object will retain features as in Level 1, but will eventually succumb to harmful agent attacks.

CCI Technical Bulletin 29.

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