Defect Atlas — Architectural Iron & Steel

Visible corrosion products on the surface of ferrous fabric without apparent loss of section.

Orange-brown, red-brown or dark corrosion films on exposed metal surfaces; sometimes uniform, sometimes patchy; underlying profile remains broadly intact.

Coating breakdown, exposure to moisture and absence of protective treatment can be associated.

• extent and distribution of corrosion product
• location relative to coating breakdown
• evidence of associated staining on adjacent fabric
• whether the original profile remains discernible

“Surface corrosion was recorded across the lower rail, with a uniform orange-brown film visible where the coating has weathered away.”

Visible features that may indicate corrosion is currently active rather than historic.

Fresh, bright orange or red-brown corrosion product on, or running from, the element; recent run-off staining on adjacent fabric; loose flake material accumulating below.

Continuing moisture contact, recent coating failure and breakdown of localised protection can be associated; activity cannot be confirmed from a single inspection.

• freshness of corrosion product relative to surrounding deposits
• evidence of recent run-off below the element
• presence of loose flake material in adjacent gutters or sills
• comparison with any photographic record from earlier surveys

“Indicators consistent with active corrosion were recorded at the base of the post, with fresh orange staining on the stone plinth and loose flake material in the surrounding bedding joint.”

Small, discrete cavities in the metal surface visible once corrosion product is disturbed or lost.

Pinpoint to small-diameter pits, isolated or clustered, sometimes haloed by darker product; sometimes only visible after light brushing of surface deposits.

Chloride contamination, sustained moisture contact and localised electrochemical activity can be associated.

• distribution and approximate density of pits
• location relative to fixings, joints or splash zones
• depth of pits where visible
• any associated corrosion staining around the pitted area

“Pitting corrosion was recorded on the cleaned face of the bracket, with clustered pits across an area of approximately 60 mm².”

Corrosion developing in layers parallel to the surface, often characteristic of wrought iron or rolled section.

Stacked, leaf-like layers of corrosion product; sometimes visible at exposed ends, edges or breaks; can result in apparent swelling of the element.

Slag-line orientation in wrought iron, water ingress along laminations and historic forging or rolling can be associated.

• location and extent of laminar corrosion
• any apparent swelling or distortion of the element
• evidence at element edges or fractured ends
• association with junctions, fixings or moisture sources

“Laminar corrosion was recorded at the cut end of the wrought iron tie, with stacked leaf-like layers and visible swelling of the section across approximately 80 mm.”

Loss of corroded surface material in flakes or scales, leaving a rougher underlying profile.

Detached or detaching plates of corrosion product and oxidised metal; pitted or roughened substrate visible at losses; loose material at the base of the element.

Long-term exposure, repeated wetting and drying and earlier laminar corrosion can be associated.

• extent of exfoliated area
• approximate size of detached plates
• character of the exposed substrate
• evidence of accumulated debris at the base of the element

“Exfoliation was recorded across the lower 200 mm of the standard, with detached plates up to approximately 25 mm across and a roughened, pitted substrate at losses.”

Apparent reduction in the cross-section of a ferrous element relative to its original profile.

Visibly thinned bars or plates; reduced flange or web depth; tapered or stepped profile relative to adjacent unaffected sections.

Sustained corrosion, repeated laminar attack and prolonged moisture contact can be associated; remaining section cannot be confirmed without measurement.

• location and extent of apparent loss
• comparison with adjacent unaffected sections
• approximate remaining dimension where measurable
• implications for any structural or supporting role

“Apparent section loss was recorded across the lower section of the column, with a visibly reduced flange depth over approximately 300 mm in length.”

Complete penetration through the thickness of a ferrous element by corrosion.

Visible holes or openings through the section; sometimes haloed by laminar corrosion; sometimes obscured by retained corrosion product until disturbed.

Advanced pitting, sustained one-sided exposure and water trapping against the back face can be associated.

• location, number and approximate size of perforations
• thickness of remaining metal at adjacent areas
• evidence of moisture pathway through the perforation
• implications for adjacent connections or coverings

“Perforation was recorded through the lower plate of the gate hinge, with a hole approximately 8 mm across and laminar corrosion around its perimeter.”

Corrosion concentrated within a narrow crevice or interface where moisture and contaminants are retained.

Corrosion product emerging from the line of a crevice; staining tracking along the interface; sometimes with associated coating failure at the crevice mouth.

Trapped moisture and contaminants within tight interfaces between metal components or between metal and other materials can be associated.

• location and length of affected crevice
• associated staining along the interface
• evidence of crevice opening or movement
• presence of debris or vegetation within the crevice

“Crevice corrosion was recorded along the interface between the railing post and the masonry, with corrosion product emerging across approximately 120 mm of the joint.”

Corrosion concentrated where two metal elements overlap, often with associated lifting of the upper element.

Corrosion product at the line of overlap; visible lifting, separation or step at the lap; sometimes with associated coating breakdown at the joint.

Moisture trapped between overlapping surfaces, breakdown of joint sealant and coating failure at the lap edge can be associated.

• location and length of affected lap
• magnitude of any associated lifting
• condition of coating at the joint line
• evidence of moisture pathway into the lap

“Corrosion at the lap joint was recorded on the canopy edging, with corrosion product along approximately 350 mm of the overlap and lifting of the upper plate by approximately 3 mm.”

Corrosion concentrated around a bolt, rivet, screw or other fixing.

Halo of corrosion product around the fixing head; staining tracking from the fixing across the surrounding surface; sometimes with associated coating breakdown.

Water ingress at the fixing, breakdown of any sealant and dissimilar metals at the fixing can be associated.

• location, type and number of affected fixings
• extent of corrosion product around each fixing
• any associated movement or loosening
• condition of surrounding coating

“Corrosion at fixings was recorded along the bracket plate, with rust-coloured haloes around four of the six bolts and staining tracking across the underlying paint.”

Corrosion proceeding beneath an apparently intact or only partially failed coating.

Raised, blistered or detached coating with corrosion product visible beneath when disturbed; sometimes with associated rust-coloured staining bleeding through the coating.

Moisture trapped beneath the coating, contamination prior to application and poor adhesion can be associated.

• extent of affected area
• whether coating remains adhered or has lifted
• evidence of corrosion product visible at coating breaks
• any associated rust-coloured bleed through the surface

“Corrosion under the coating was recorded across the sheltered face, with raised blisters across approximately 0.4 m² and visible corrosion product beneath broken blisters.”

Corrosion concentrated at the base of an element where it meets ground, paving or supporting structure.

Marked accumulation of corrosion product at the lowest part of the element; sometimes with associated section loss, swelling or distortion.

Splash, soil contact, retained moisture at the interface and salt-laden run-off can be associated.

• extent and height of affected zone
• evidence of swelling, distortion or section loss
• condition of the supporting substrate or paving
• presence of drainage or ground clearance at the base

“Heavy corrosion at the base was recorded on the railing standard, with marked product accumulation over the lower 150 mm and visible swelling of the section.”

Raised bubbles within a paint or other protective coating, indicating localised loss of adhesion.

Domed or raised areas in the coating, intact or broken, sometimes containing moisture or corrosion product.

Moisture beneath the coating, contamination prior to application and incompatible layers can be associated.

• size and distribution of blisters
• whether blisters appear intact or broken
• presence of corrosion product or moisture beneath broken blisters
• underlying substrate condition where visible

“Coating blistering was recorded across the upper rail, with several broken blisters exposing rust-coloured product beneath.”

Detachment of a coating in flakes, exposing the metal substrate or earlier coating layers.

Lifted, curled or detached flakes of coating, sometimes retaining several layers; substrate or earlier paint visible at losses.

Coating ageing, underlying corrosion, repeated thermal cycling and inadequate preparation can be associated.

• extent of flaking
• approximate size of detached areas
• condition of exposed substrate
• any evidence of active loss

“Coating flaking was recorded across the top rail, with detached flakes up to approximately 20 mm across exposing corrosion-stained substrate beneath.”

Linear discontinuities through one or more layers of a coating.

Fine to wide cracks across the coating film, sometimes following section transitions, weld lines or fixings; cracks may pass through coating only or further.

Coating ageing, applications of brittle systems over more flexible layers and movement of the substrate can be associated.

• orientation and approximate width of cracks
• whether cracks coincide with section features
• evidence of corrosion staining at crack lines
• extent across the element

“Coating cracking was recorded across the cast bracket, with fine cracks broadly aligned with the casting profile and faint rust-coloured staining at several lines.”

Formation of a fine, loose powder on the surface of a weathered coating.

Pale, dusty bloom transferring readily to a finger; often with associated dulling of colour and gloss; concentrated on exposed orientations.

UV exposure, binder degradation and long-term weathering of exterior coatings can be associated.

• extent of chalking across the element
• association with sun-exposed faces
• transfer of powder to a light wipe
• any associated loss of gloss or colour

“Coating chalking was recorded across the south-facing face of the railing, with a fine pale bloom transferring readily on a light wipe.”

Discrete areas where the coating is absent and the substrate or an earlier layer is exposed.

Bare or thinly coated areas with sharper colour contrast against the surrounding finish; sometimes with associated corrosion at the exposed metal.

Abrasion, mechanical damage, earlier corrosion and incomplete previous repainting can be associated.

• extent, location and shape of losses
• character of the exposed surface
• presence of associated corrosion at exposed metal
• evidence of earlier patch repainting

“Coating loss was recorded at the handle of the gate, with bare metal exposed across an area approximately 80 mm long and a fine corrosion film developing on the substrate.”

A more recent coating layer showing widespread failure over an apparently more stable underlying system.

Most recent layer flaking, peeling or lifting in sheets; earlier layers beneath appearing more adhered; sometimes with mismatch in colour, gloss or texture between layers.

Application over poorly prepared surfaces, contamination at the interface and incompatibility between coatings can be associated.

• extent of failure of the most recent layer
• relative condition of underlying layers
• evidence of preparation between layers
• any documentary record of the last redecoration

“Failed overcoating was recorded across the railing, with the most recent layer lifting in sheets while the earlier system remained largely adhered beneath.”

Visible weathering of a galvanised surface, with possible breakdown of the zinc layer.

Dull, mottled or whitened galvanised surface; sometimes with white corrosion product; isolated rust spots where the zinc may be locally lost.

Long-term exposure, salt-laden environments and abrasion of the zinc layer can be associated; remaining zinc thickness cannot be confirmed from visual observation.

• extent and distribution of weathering
• presence of white zinc corrosion product
• any isolated rust spots indicating possible local loss
• comparison between exposed and sheltered faces

“Galvanising weathering was recorded across the post, with a dull, mottled surface and isolated rust spots at the upper edge where the zinc layer may be locally lost.”

A bolted fixing that is still in place but no longer fully restrained.

Movement under light hand pressure; visible gap between bolt head, washer or fixed element; corrosion or staining around the bolt.

Corrosion at the fixing, loss of bedding mortar, vibration and earlier disturbance can be associated.

• location and number of affected bolts
• degree of movement
• evidence of associated damage to substrate
• implications for adjacent connections

“A loose bolt was recorded at the upper bracket, with visible movement when light hand pressure was applied and faint rust staining around the head.”

A fixing absent from a position where one was originally present.

Empty hole, recess or scar in the substrate; visible witness mark or staining around the former fixing; sometimes with associated movement of the fixed element.

Earlier removal, corrosion to failure, impact or earlier maintenance can be associated.

• location and number of missing fixings
• evidence of original fixing type at the witness mark
• any associated movement of the element
• condition of the host substrate

“A missing fixing was recorded at the lower bracket, with an empty hole approximately 10 mm across and a faint corrosion halo around its perimeter.”

A riveted connection showing apparent loss of integrity at the rivet head or shank.

Missing or sheared rivet head; visible movement at the connected plates; corrosion product around the rivet position; sometimes with visible opening of the joint.

Long-term corrosion, fatigue, earlier impact and overload can be associated.

• location and number of affected rivets
• evidence of associated movement or joint opening
• condition of surrounding rivets in the same connection
• presence of corrosion at the connection

“A failed rivet was recorded at the third position along the bracket, with the head missing, visible movement at the joint and corrosion product around the shank position.”

A linear discontinuity through or alongside a welded joint.

Visible crack along, through or at the toe of a weld; sometimes with associated corrosion product following the crack; sometimes with movement at the joint.

Original weld quality, fatigue, overload, corrosion-induced stress and thermal movement can be associated; weld condition cannot be confirmed without inspection.

• location and length of the crack
• orientation relative to the weld run
• evidence of associated movement or staining
• condition of the parent material adjacent to the weld

“A cracked weld was recorded at the underside of the rail-to-post connection, with a linear crack approximately 40 mm long following the line of the weld toe.”

An earlier welded repair that is showing apparent loss of integrity.

Cracking through or alongside an earlier weld bead; visible separation or movement at the repaired joint; corrosion concentrated along the repair line.

Earlier weld quality, dissimilar metal interaction, fatigue and continued movement can be associated.

• location and extent of the failed repair
• evidence of original damage that prompted the repair
• comparison with adjacent original welds
• implications for the overall connection

“A failed weld repair was recorded at the base plate, with cracking through the repair bead and corrosion product following the line of the earlier weld.”

Visible separation between components that were originally fitted closely or sealed.

Gap at junctions where none was originally intended; daylight visible through the assembly; ingress of debris, water or vegetation; sometimes with associated rust staining.

Movement, corrosion-induced expansion, fixing failure and breakdown of bedding mortar can be associated.

• location and width of opening
• evidence of associated movement
• presence of debris or moisture within the gap
• implications for shedding water from the assembly

“An open joint was recorded between the base plate and the masonry, with a gap up to approximately 5 mm at the front edge and rust staining tracking down the plinth.”

Visible evidence of movement between a fixing and the element or substrate to which it is attached.

Witness marks, polished arcs or smeared coating around the fixing; opening or closing of joints relative to the fixing; sometimes with associated cracking of mortar or coating around the fixing.

Thermal cycling, vibration, load reversal and earlier disturbance can be associated.

• location and direction of apparent movement
• presence of witness marks or polished arcs
• any associated cracking of substrate or coating
• comparison with adjacent stable fixings

“Movement at the fixing was recorded at the lower bracket bolt, with a polished arc on the painted surface around the bolt and fine cracking of the bedding mortar.”

General departure of a ferrous element from its intended geometry.

Bowing, twisting, sagging or out-of-plane movement assessed against adjacent unaffected sections or a straight reference.

Impact, overload, thermal movement, support loss and long-term creep can be associated.

• type and direction of distortion
• approximate magnitude where measurable
• extent across the element
• comparison with adjacent components

“Distortion was recorded across the central bay of the railing, with a visible bow of approximately 25 mm out of plane.”

Localised bending or deflection of a bar, rail or section away from its original alignment.

Curved or angled departure from the original straight line; sometimes with visible kink at a defined point; sometimes with associated coating cracking on the convex face.

Impact, overload, leverage and earlier disturbance can be associated.

• location and apparent magnitude of bending
• evidence of any associated coating or paint cracking
• comparison with adjacent unbent sections
• any evidence of historic versus recent bending

“Bending was recorded in the upper rail, with a localised kink of approximately 15 mm and associated cracking of the coating on the convex face.”

Physical damage from impact with a vehicle, equipment or other object.

Dents, gouges, scrapes, fractured edges, missing fragments and associated coating loss at impacted areas.

Vehicle contact, accidental impact, maintenance activity and vandalism can be associated.

• type, location and extent of damage
• any exposure of substrate beneath coating
• evidence of repeated impact
• implications for adjacent elements

“Impact damage was recorded on the lower section of the gatepost, with a dent approximately 80 mm across and associated coating loss consistent with vehicle contact.”

Complete or partial fracture through a ferrous element.

Visible break or part-break across the section; sometimes with rust-stained or freshly exposed fracture face; sometimes with associated displacement of the fractured ends.

Impact, overload, fatigue, embrittlement and earlier damage can be associated; cause cannot be confirmed from visual observation.

• location and orientation of the fracture
• character of the fracture face — granular, fibrous, layered
• evidence of associated displacement
• presence of any earlier repair at or near the fracture

“A fractured element was recorded at the lower scroll, with a complete break across the section and a freshly exposed granular fracture face.”

Visual indicators that may be associated with fatigue cracking, particularly at high-stress locations.

Fine, often straight cracks at section changes, weld toes, holes or other stress raisers; sometimes accompanied by faint rust staining along the crack line.

Repeated loading, vibration, wind action and stress concentration at section features can be associated; confirmation requires non-destructive testing.

• location of cracks relative to stress raisers
• orientation, length and approximate width
• presence of associated rust staining along cracks
• history of vibration, loading or movement at the element

“An indicator consistent with possible fatigue cracking was recorded at the bracket-to-rail weld toe, with a fine, straight crack approximately 25 mm long and faint rust staining along its length.”

Corrosion patterns that may be associated with galvanic action between dissimilar metals in contact.

Accelerated corrosion concentrated at the interface between dissimilar metals; characteristic localised attack on the more anodic metal; sometimes with associated staining.

Direct contact between dissimilar metals in the presence of an electrolyte such as rainwater can be associated; metal identification cannot be confirmed visually.

• location of dissimilar metal contact
• evidence of accelerated corrosion on one of the metals
• presence of moisture pathway across the junction
• any evidence of earlier isolation that has failed

“An indicator consistent with possible galvanic corrosion was recorded at the junction between the ferrous bracket and the copper rainwater pipe, with accelerated corrosion on the ferrous element at the line of contact.”

Discolouration on or around metal elements that may be associated with corrosion products from a dissimilar adjacent metal.

Green, blue-green or dark stains tracking from copper or copper-alloy elements onto adjacent ferrous fabric; brown stains from ferrous corrosion onto non-ferrous metals.

Rainwater run-off between metals of differing types can be associated.

• source metal and direction of run-off
• extent and intensity of staining
• evidence of associated corrosion on either metal
• any visible failed isolation between the metals

“Bimetallic staining was recorded on the iron bracket below the copper downpipe, with a green-blue stain extending approximately 200 mm down the painted surface.”

Localised corrosion of a ferrous element where it is restrained or fixed by a non-ferrous component.

Accelerated corrosion of the ferrous element around the non-ferrous fixing; sometimes with associated staining and coating breakdown at the junction.

Contact between ferrous and non-ferrous fixings in the presence of moisture can be associated.

• type and number of affected junctions
• extent of corrosion on the ferrous element
• any associated staining or coating failure
• evidence of moisture pathway to the junction

“Corrosion at the junction with the non-ferrous fixing was recorded at three positions along the rail, with localised accelerated corrosion around each fixing.”

A detail or condition in which water is retained against or within a ferrous element.

Pooling, residual moisture, debris-filled junctions or saturated assemblies; sometimes with associated corrosion product and staining.

Original detailing, blocked drainage, debris build-up and distortion of components can be associated.

• location and character of the trap
• evidence of repeated wetting
• associated corrosion or staining
• presence of debris or vegetation

“A water trap was recorded at the junction between the post and the base plate, with associated corrosion product and rust staining tracking onto the masonry below.”

A drainage hole, channel or path that is no longer functioning because of blockage.

Drainage feature partially or fully obstructed by debris, vegetation, paint or corrosion product; sometimes with associated water staining above the blockage.

Debris accumulation, repeated overpainting, biological growth and earlier coating campaigns can be associated.

• location and type of drainage feature
• extent of blockage
• evidence of associated water retention or staining
• any visible history of past clearance

“A blocked drainage point was recorded at the lower edge of the box section, with the weep hole obstructed by paint and corrosion product and a vertical run-off stain below.”

Accumulated debris retained against, within or beneath ferrous fabric.

Leaves, soil, packed dirt or other material lodged in channels, behind plates or within hollow sections; sometimes with associated moisture and corrosion.

Wind, vegetation, run-off pathways and lack of maintenance can be associated.

• location and type of debris
• estimated volume or depth of accumulation
• associated moisture or corrosion at the debris contact zone
• accessibility for maintenance

“Trapped debris was recorded in the channel between the gate frame and the post, with packed leaf litter approximately 30 mm deep and associated corrosion staining at the contact face.”

Loss of integrity of a sealant or mastic intended to prevent moisture entering a metal interface.

Cracked, torn, missing or hardened sealant at junctions; visible gap between sealant and substrate; sometimes with associated staining or corrosion at the interface.

Sealant ageing, movement across the joint, original application conditions and earlier overpainting can be associated.

• location and length of affected sealant
• type of failure observed
• evidence of moisture pathway through the failed sealant
• any associated corrosion at the interface

“Failed sealant was recorded along the upper edge of the base plate, with the sealant cracked and pulled away from the masonry across approximately 200 mm and associated rust staining at the interface.”

An earlier weld bead or build-up applied to repair damage or section loss.

Visible weld bead of differing colour, texture or profile to the parent material; sometimes with visible heat-affected zone; sometimes with associated coating disruption.

Past repair campaigns, earlier damage and historic maintenance can be associated.

• location, extent and apparent age of the repair
• evidence of original damage at the repair location
• apparent condition of the repair
• compatibility with surrounding original fabric where assessable

“A previous welded repair was recorded at the lower scroll, comprising a build-up of weld material across approximately 60 mm and a clearly visible heat-affected zone.”

An earlier repair using a flat or shaped plate bolted, riveted or welded over original fabric.

Additional plate of differing profile, thickness or finish to the parent element; visible fixings or weld lines around the perimeter; sometimes with associated corrosion at the plate edges.

Past repair to address loss or damage, and historic strengthening can be associated.

• location, type and size of repair plate
• type of fixing used
• condition of the repair plate
• evidence of corrosion or movement at the perimeter

“A plate repair was recorded on the rear face of the base plate, comprising a steel plate approximately 200 by 150 mm fixed with four bolts and showing perimeter rust staining.”

An earlier repair using a metal of different type to the original fabric, where this may not be performing as intended.

Insert of differing colour, finish or weathering to the parent metal; sometimes with associated accelerated corrosion at the junction; sometimes with visible bimetallic staining.

Past repair using readily available material rather than matching metal can be associated.

• location and extent of the insert
• evidence of differing weathering behaviour
• any associated corrosion or staining at the junction
• implications for adjacent fabric

“An incompatible metal insert was recorded at the lower rail, with a section of mild steel set within the surrounding wrought iron and accelerated corrosion at the junction.”

An earlier repair using resin, filler or other non-metallic material to fill loss or conceal damage.

Smoother or differently textured area within the metal element; sometimes with visible cracking around the perimeter; sometimes with discolouration relative to the surrounding paint.

Past cosmetic repair, attempted concealment of corrosion or attempted reinstatement of profile can be associated.

• location, size and extent of the repair
• evidence of cracking or separation at the perimeter
• any indication of corrosion continuing beneath the repair
• whether the repair is performing in its intended role

“A resin or filler repair was recorded on the lower section of the post, with a smoother area approximately 80 mm across and cracking around the perimeter.”

Corrosion concentrated on or around the base plate that anchors a column, post or standard.

Corrosion product across the upper or lower face of the base plate; staining tracking from the plate onto adjacent paving or masonry; sometimes with apparent section loss at the plate.

Water retention on or around the plate, splashing, salt-laden run-off and embedded contact with the substrate can be associated.

• extent of corrosion across the plate
• evidence of associated staining on adjacent paving or stone
• apparent loss of section at the plate
• condition of fixings through the plate

“Base plate corrosion was recorded at the gatepost, with corrosion product across the upper face of the plate and rust staining extending across the paving on the downslope side.”

Staining and disruption associated with the expansion of corroding metal embedded within stone, brick, concrete or render.

Rust staining emerging from the substrate around a ferrous insert; sometimes with associated cracking, spalling or displacement of the host material.

Corrosion of an embedded fixing, cramp, dowel or armature within the substrate can be associated; condition of the embedded metal cannot be confirmed visually.

• location of embedded element
• extent of staining and any associated cracking
• presence of associated displacement or spalling
• any evidence of the embedded fixing emerging through the substrate

“Embedded metal expansion staining was recorded around the iron cramp in the stone parapet, with rust staining extending approximately 80 mm and an associated fine crack in the stone.”

Ferrous fabric in direct or near contact with ground, paving or soil, with limited clearance for drying or drainage.

Element seated directly on or below adjacent paving level; soil banked against the element; concentrated corrosion at the contact zone.

Ground level raised by surface treatments, paving build-up, soil accumulation and original detailing can be associated.

• vertical relationship of the element to surrounding ground
• evidence of past higher clearance
• extent of corrosion at the contact zone
• drainage characteristics of the adjacent ground

“Inadequate clearance from ground was recorded at the railing standard, with the element seated within the build-up of paving and concentrated corrosion across the lower 100 mm.”

Distortion that may be associated with restrained thermal movement of long metal runs.

Bowing, lateral displacement or rotation in long runs, particularly between fixings; sometimes with associated cracking of bedding mortar or coating at restrained points.

Continuous lengths without provision for movement, restraint at fixings and exposure to temperature variation can be associated.

• extent and pattern of distortion
• spacing of fixings and any provision for movement
• evidence of associated cracking at restrained points
• comparison between exposed and sheltered runs

“Distortion consistent with thermal movement was recorded along the south-facing run of railing, with a visible lateral bow between fixings and fine cracking of mortar at restrained points.”

Visible features that may indicate loss of anchorage of an element to its supporting structure.

Movement of the element under light pressure; opened or stepped joint at the anchorage; cracking, spalling or staining at the anchorage point; tilt or rotation relative to adjacent stable elements.

Corrosion at the anchorage, loss of bedding mortar, movement of the supporting structure and earlier disturbance can be associated.

• location and type of anchorage
• evidence of movement or rotation
• condition of the surrounding substrate
• implications for public safety where accessible

“An indicator consistent with failed anchorage was recorded at the corner standard, with visible rotation relative to adjacent stable posts and cracking of the surrounding stone.”

Rust-coloured staining on stone, brick, render, paint or other adjacent fabric, associated with corroding ferrous elements.

Brown, orange or dark streaks tracking down or across adjacent fabric, often in run-off pathways; sometimes with concentrated staining at projecting fixings.

Rainwater run-off from corroding ferrous elements above the staining can be associated.

• source ferrous element where identifiable
• extent and direction of staining
• substrate affected
• association with detailing or drainage

“Corrosion staining on adjacent fabric was recorded on the limestone plinth below the iron fixing, with brown streaks extending approximately 400 mm down the stone.”

Distinct linear staining on surfaces below ferrous fabric, associated with concentrated rainwater run-off.

Vertical, diagonal or fan-shaped rust-coloured staining following defined run-off pathways; sometimes with associated etching of the substrate.

Concentrated drips, rainwater run-off pathways and the position of corroding fabric can be associated.

• location and form of run-off staining
• association with specific drip or run-off points
• extent and intensity of staining
• any associated etching or surface change in the substrate

“Rust run-off staining was recorded on the pavement below the bracket, with a fan-shaped stain extending approximately 600 mm from the wall face.”

Staining concentrated on adjacent paving or masonry around the base plate of a freestanding element.

Rust halo on paving around the base plate; staining tracking from the plate edges across the substrate; sometimes with associated etching of the paving.

Corrosion at and around the base plate, water shedding from the element and pooling around the plate can be associated.

• extent and shape of the staining halo
• association with prevailing run-off direction
• evidence of pooling around the plate
• condition of the paving beneath the stain

“Staining at the base plate was recorded around the railing post, with a rust halo across the paving extending approximately 150 mm from the plate edges.”

A baluster, rail or balustrade element with visible movement when handled.

Movement under light hand pressure; opened or stepped joint at the fixing; sometimes with associated corrosion or mortar loss at the connection.

Corrosion at fixings, loss of bedding, impact and earlier disturbance can be associated.

• location and number of affected elements
• degree of movement under light pressure
• evidence of associated damage at the connection
• level of public access to the element

“A loose baluster was recorded at the third position from the corner, with visible movement when light pressure was applied and faint rust staining at the lower fixing.”

An exposed sharp edge, point or fractured end that may present a hazard at handled or accessible heights.

Broken, fractured or corroded edge with exposed sharp points; sometimes at handle heights, thresholds or pedestrian routes; sometimes with associated coating loss.

Impact, fracture, corrosion to point and earlier damage can be associated.

• location, accessibility and apparent sharpness
• height relative to typical handling
• any associated movement at the element
• exposure to vulnerable user groups where relevant

“A sharp edge was recorded at the lower rail of the gate, with a fractured end exposed at hand height and associated coating loss.”

A missing finial, cap or end cover from a post, baluster or hollow section.

Open end of post or section; visible internal cavity; sometimes with associated water ingress and internal corrosion; sometimes with witness mark or fixing remains for the missing cap.

Loss through corrosion, impact, theft or earlier removal can be associated.

• location and number of missing caps
• evidence of the original cap type
• any associated internal corrosion or water ingress
• implications for public safety on accessible elements

“A missing protective cap was recorded at the corner standard, with the open hollow section exposed and corrosion visible on the internal surface.”

A general visible condition with possible implications for public safety, recorded for prompt onward review.

Conditions such as displaced elements, projecting fixings, accessible loose components or open hollow sections in publicly accessible locations.

Loss, displacement, failure or removal of original components can be associated.

• nature, location and accessibility of the condition
• user groups likely to be affected
• any temporary measures already in place
• urgency relative to other observations

“A public safety observation was recorded at the boundary railing, with a projecting fractured bar at hand height alongside the pedestrian route.”