Atch_24_Post_Investigation_Report.pdf

SCOTT AIR FORCE BASE

TERMITE DAMAGE / STRUCTURAL INTEGRITY ASSESSMENT B861

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08/29/11 K:\SAFB\BV\170021-0004 SAFB Termite Damage\01 Administration\09 Reports\Basis of Design\B861\2018-03-13 Final Report\214_Post Investigation Analysis Report B861-2018-03-13.docx

POST INVESTIGATION ANALYSIS REPORT

On Tuesday, January 23, 2018, representatives of Kuhlmann design Group, Inc.

performed a site visit to Building 861 located on Scott Air Force Base with the intent to observe the structural framing and architectural composition of the building structure, assess known instances of existing termite and water damage, evaluate the structural integrity of the building as a result of this damage, and report the findings of this investigation. This Post Investigation Analysis Report summarizes the observations and assessments made during the site visit.

The investigation performed was principally visual in nature, with supplemental mechanical testing performed to evaluate the structural soundness of individual members as deemed warranted by visual inspection. Non-Structural items, such as insulation, HVAC, electrical wiring, ventilation, etc. were not evaluated as part of this investigation.

EXISTING BUILDING STRUCTURE

The area of Building 861 is approximately 42,200 square feet, and is comprised of a central building running from east to west on plan, as well as four pairs of “wings” that run plan north and south from this central building. These five areas are reflected in Appendix A Figure 1, which illustrates the overall floor plan of Building 861.

The building structure is a traditional post and beam framing system that utilizes heavy timber truss fabrications supported on timber columns to support roof loads and transfer these loads into the foundation. Wood framed walls infill between this post and beam framing and comprises the remainder building structure. The bottom of the roof trusses are clad with gypsum board with the attic protected by a dry suppression system.

The framed walls rest on a 3x6 plate atop a continuous 6” concrete curb. The floor structure is constructed of a concrete slab on grade system, of thickness and reinforcing unknown due to the lack of original building drawings.

Overall these five principal areas comprise the entirety of Building 861, and were observed for past and present termite and water damage during the course of the site investigation. The findings are as follows.

OBSERVATIONS AND ASSESSMENTS

To observe the structure and assess any discovered damage from wood destroying insects and/or water penetration, 32 wall access points were utilized. These access

2 0097-001 points and their locations are shown in Appendix A Figure 1, and are referenced throughout the remainder of this report.

Note: During the course of our investigation, no active termite activity or water intrusion was observed. The absence of termite activity was likely due to the cold temperatures during the time of our visit, resulting in a cold and dry environment in the wall cavity space. This is not to infer that termite activity has ceased, but may fluctuate seasonally as conditions become more or less optimal for termite activity. Termites can often go dormant when conditions are unfavorable, returning deeper underground to warm and moist areas. Mud tubes were observed in several areas around the building (see Appendix A Figure 1) along with numerous areas with moisture penetration. Larger images of the photographs in the report are located in Appendix C.

Wall Framing Access Point 1 Location: Room 410

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Signs of extensive termite activity and excessive water penetration (paint cracking and peeling). Observable damage has occurred to jack studs, window sill plates, cripples and jack studs at both window locations. Wall mounted wire raceway blocked ability to cut opening at floor plate.

Structural Assessment: The damage caused in this area is major. The wood window framing has deteriorated to the extent that large pieces are easily spalled off with little effort using hand tools. This termite damage can result in windows not opening properly and the glazing cracking.

Photos:

Wall Framing Access Point 2 Location: Room 408

Observations: Limited due equipment on walls and wall mounted wire raceway.

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Wall Framing Access Point 3 Location: Room 400

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

No signs of past termite activity. There are visible signs of past water penetration (damp insulation, mold on wall cavity side of gypsum board). No photographs allowed due to being a secured space.

Structural Assessment: No framing damage. Presence of moisture could lead to termite activity and deterioration of wood framing in the future.

Wall Framing Access Point 4 Location: Room 404

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

There are signs of water penetration at window (peeling/cracking paint, damp insulation and rusty anchor bolt). No photographs allowed due to being a secured space.

Structural Assessment: No framing damage. Presence of moisture could lead to termite activity and deterioration of wood framing in the future.

Wall Framing Access Point 5 Location: Room 405A

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Signs of extensive termite activity and excessive water penetration (paint cracking and peeling). Severe damage has occurred to jack studs, window sill plates, cripples and jack studs at east window location.

Structural Assessment: The damage caused in this area is major. The wood window framing has deteriorated to the extent that large pieces have disintegrated or are easily spalled off with little effort using hand tools. The termite damage can result in windows not opening properly and the glazing cracking.

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Wall Framing Access Point 6 Location: Room 403

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

No signs of past termite activity. There are visible signs of past water penetration (damp insulation).

Structural Assessment: No damage to framing. Presence of moisture could lead to termite activity and deterioration of wood framing in the future.

Wall Framing Access Point 7 Location: Room 300E

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

No signs of past termite activity. There are visible signs of past water penetration (damp insulation, mold on wall cavity side of gypsum board and rusty anchor bolts).

Structural Assessment: No damage to framing. Presence of moisture could lead to

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Wall Framing Access Point 8 Location: Room 300J

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

No signs of past termite activity. There are visible signs of past water penetration (damp insulation and mold on wall cavity side of gypsum board).

Structural Assessment: No damage to framing. Presence of moisture could lead to

Wall Framing Access Point 9 Location: Room 300L

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

This portion of wall must be an infill with use of plywood sheathing and cardboard filler.

No sign of termite activity or water penetration.

Structural Assessment: No damage to framing. Presence of cardboard could be an attraction for termite damage.

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Wall Framing Access Point 10 Location: Room 300

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

There are visible signs of past water penetration (peeling paint, water stains on wood framing, damp insulation and mold on wall cavity side of gypsum board).

Structural Assessment: Wood framing is currently dry. Presence of moisture could lead to termite activity and deterioration of wood framing in the future

Wall Framing Access Point 11 Location: Mechanical Room

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Observable past termite activity or damage (bore tunnels) and past water penetration or damage (water stains on wood framing and damp insulation).

Structural Assessment: Minimal damage to wood stud framing. The presence of moisture could lead to termite activity and deterioration of wood framing in the future.

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Wall Framing Access Point 12 Location: Room 203

Observations: No access available due to cubicles along wall. No photographs due to being a secured space.

Wall Framing Access Point 13 Location: Room 203

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Observable past termite activity or damage (bore tunnels) and past water penetration or damage (deteriorated wood framing and damp insulation). No photographs allowed due to being a secured space.

Structural Assessment: Major damage to 3x6 sill plate. Presence of moisture will lead to continued termite activity and deterioration of wood framing.

Wall Framing Access Point 14 Location: Room 204

Observations: No access available due to cubicles along wall. No photographs due to being a secured space.

Wall Framing Access Point 15 Location: Men’s Room 300

Observations: The existing built up wood post bears on top of a 6” high concrete curb.

Wood stains on built-up post but wood is dry. Mud tubes are visible on exterior of building adjacent to this area.

Structural Assessment: No visible damage to built-up post. The past issue of the water penetration and the adjacent mud tubes future termite activity and deterioration of wood framing is possible.

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Wall Framing Access Point 16 Location: Room 101

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Framing and insulation are dry. Sill plate has signs of possible termite bore tunnels.

Structural Assessment: No observable damage to framing from water penetration and very minimal termite damage.

Wall Framing Access Point 17 Location: Room 1012

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Wood framing has stains from past water penetration. Framing and insulation are dry. Sill plate has signs of possible termite bore tunnels.

Structural Assessment: No observable damage to framing from water penetration and

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Wall Framing Access Point 18 Location: Room 101

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Wood framing has stains from past water penetration. Framing and insulation are dry. Sill plate has signs of possible termite bore tunnels and did not sound solid. Mud tubes along with wood chip landscaping on the exterior of this wall.

Structural Assessment: No observable damage to framing from water penetration and

Wall Framing Access Point 19 Location: Room 150A

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

There are signs of past water penetration (rusty anchor bolt). Framing and insulation are dry.

Structural Assessment: No damage to framing. Presence of moisture could lead to termite activity and deterioration wood framing in the future.

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Wall Framing Access Point 20 Location: Room 152

Observations: No access room was locked.

Wall Framing Access Point 21 Location: Room 155

Observations: No access room was locked.

Wall Framing Access Point 22 Location: Room 158

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Insulation is damp. Sill plate has signs of possible termite bore tunnels.

Structural Assessment: No observable damage to framing from water penetration and very minimal termite damage. Presence of moisture could lead to termite activity and deterioration of wood framing in the future.

Wall Framing Access Point 23 Location: Room 162

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Insulation is wet with deteriorated paper backing and wood framing is wet. Abandon copper pipe possibly an old condensate pipe from a fan coil unit is present.

Structural Assessment: No damage to framing. Presence of moisture could lead to

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Wall Framing Access Point 24 Location: Room 254

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Visible signs of water penetration (wet insulation, rusty anchor bolt, and mold on wall cavity side of gypsum board). Wood framing is damp.

Structural Assessment: No observable damage to framing from water penetration.

Presence of moisture could lead to termite activity and deterioration of wood framing in the future.

Wall Framing Access Point 25 Location: Room 255

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Visible signs of water penetration (wet insulation, and mold on wall cavity side of gypsum board). Wood framing is dry.

Structural Assessment: No observable damage to framing from water penetration.

Presence of moisture could lead to termite activity and deterioration of wood framing in

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Wall Framing Access Point 26 Location: Room 259

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Visible signs of water penetration (wet insulation, and mold on wall cavity side of gypsum board). Wood framing is damp.

Structural Assessment: No observable damage to framing from water penetration.

Presence of moisture could lead to termite activity and deterioration of wood framing in

Wall Framing Access Point 27 Location: Room 351

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Visible signs of water penetration (wet insulation, and mold on wall cavity side of gypsum board). Wood framing is damp. No photographs allowed due to being a secured space.

Structural Assessment: No observable damage to framing from water penetration.

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Wall Framing Access Point 28 Location: Room 355C

Observations: Room is under construction to repair previous water/termite damage. No opening was cut. Mud tubes were present on outside wall.

Wall Framing Access Point 29 Location: Room 355D

Observations: Room is under construction to repair previous water/termite damage. No opening was cut.

Wall Framing Access Point 30 Location: Room 356

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Visible signs of water penetration (damp insulation, wood framing is damp/stained and mold on wall cavity side of gypsum board).

Structural Assessment: No observable damage to framing from water penetration.

Presence of moisture could lead to termite activity and deterioration of wood framing in

Wall Framing Access Point 31 Location: Room 360

Observations: The existing wood wall framing bears on top of a 6” high concrete curb.

Visible signs of water penetration (wet insulation, and mold on wall cavity side of gypsum board). Wood framing is damp.

Structural Assessment: No observable damage to framing from water penetration.

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Wall Framing Access Point 32 Location: 409

Observations: The existing wood wall framing bearing on top of 6” high concrete curb.

The existing stud framing and sill plate is painted white making observation of termite and/or water damage difficult. No photographs allowed due to being a secured space.

Structural Assessment: No observable damage to framing from water penetration.

Building Attic Access Location: Attic

Observations: Confirmation of post and beam truss framing style. No observable past termite activity or damage. Minimal observable past water penetration or damage.

Structural Assessment: The existing central building is of post and beam construction supporting heavy timber trusses that comprise the roof structure. No observable damage or deterioration was observed at the base of the structural post; either from termite activity or water penetration.

CONCLUSIONS

On Tuesday January 23, 2018, representatives of Kuhlmann design Group, Inc.

performed a site visit to Building 861 located on Scott Air Force Base with the intent to observe the structural framing and architectural composition of the building structure, assess known instances of existing termite and water damage, evaluate the structural integrity of the building as a result of this damage, and report the findings of this investigation. This Post Investigation Analysis Report summarizes the observations and assessments made during the site visit.

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The investigation performed was principally visual in nature, with supplemental mechanical testing performed to evaluate the structural soundness of individual members as deemed warranted by visual inspection. Non-Structural items, such as HVAC, electrical wiring, ventilation, etc. were not evaluated as part of this investigation.

The area of Building 861 is approximately 42,200 square feet, and is comprised of a central building running from east to west on plan, as well as four pairs of “wings” that run plan north and south from this central building. These five areas are reflected in Appendix A Figure 1, which illustrates the overall floor plan of Building 861.

Damage to the infill framed walls is prevalent throughout the building structure at various locations across the entire footprint. This damage is the result of past and recent termite activity, as well as past and recent water penetration. While many areas exhibit minimal current damage, termite damage can often be more widespread and concealed than is visually observable.

Overall, the most severe damaged areas are around the existing widows. Dislocated window sills and failed sealants are allowing moisture to penetrate into the building. This moisture along with warm temperatures can promote termite activity, resulting in partial failure of specific window framing elements (namely jack and king studs, cripples, and sill plates – see Appendix B Figure 2). This failure can result in windows not operating, cracked glazing or the window unit falling out of the wall.

The existing fan coil units (FCU) could be a source of water penetration. Numerous air intake vents for the FCUs are currently open or have a mesh screen in place of a louver.

This condition can allow for windblown rain to enter the FCU and/or the building.

In addition the condensate pipe from the FCUs is run between the sheathing and the thin brick veneer. The pipe terminates at the base of the thin brick veneer which provides an opportunity for wind driven condensation to saturate the sheathing and penetrate into the building.

The base of the existing thin brick veneer has started to break apart along the base at many locations on the exterior walls around the building. This failure has left wood materials exposed and provides the opportunity for water penetration into the building.

This penetration can lead to deterioration of the wood framing and along with warm temperatures can promote termite activity.

There are numerous sections of existing gutter with joints incorrectly lapped or not sealed properly. This allows water to leak out and wash the base of the thin brick veneer.

The areas are easily identified by the dark stains on the base of the brick. With the base

16 0097-001 of the thin brick veneer breaking up it allows the opportunity for water to penetrate into the building.

The building has several planting areas with wood chips used for mulch. Wood chips can be source for termites. Also there are several areas around the building where the grade is within several inches of the base of the thin brick veneer which allows for water penetration and access for termites.

Without proper treatment and or repair, this termite activity appears likely to continue when conditions are favorable for termite activity (warmer temperatures and higher moisture levels in the spring and summer seasons). Continued activity will cause further degradation of the infill wall framing, and can eventually begin to compromise the post and beam structure. Care should be taken to restrict access to the known areas of structural degradation until further action is taken to remediate the situation.

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