Diagnostic Methods and A/E Design Solutionsmybasementdigout.com/downloads/mold/mold_presentation.pdf · Diagnostic Methods and A/E Design Solutions Greg Baker, CIH, CSP, CHMM AMEC

Diagnostic Methods and A/E Design Solutions

Greg Baker, CIH, CSP, CHMMAMEC Earth & Environmental, Inc.

October 17, 2006

Three Questions…

Why Does Mold Grow in Building Envelopes?

How Do You Deal With Mold?

How Do You Design To Avoid Mold?

Why Does Mold Grow in Building Envelopes?

Too Much Water !

In the liquid stateIn the vapor stateIn the solid (ice) state transitioning to liquid

…and insufficient means to prevent, inhibit, control, manage and remove excess moisture

Why Does Mold Grow in Building Envelopes?

• Failure to prevent and control excess moisture• Poor design: By design buildings are…• Inadequate planning, material sequencing, etc• Circumstances / poor choices

Why Does Mold Grow in Building Envelopes?

• Insufficient construction management • Inadequate QA/QC• Insufficient commissioning• Lack of proper maintenance• And….inadequate or untimely responses

How Do You Deal With Mold?

Resolve moisture issuesRemove suspect visible mold and debris following established guidelines (i.e., the standard of care)

How Do You Deal With Mold?

Proactively

How Do You Deal With Mold?

ProactivelyRisk = Hazard + Outrage

Tomoko Kurauchi Age 115

How Do You Deal With Mold?

Plan ahead to prevent moisture & moldManage construction activities (CM)Include 3rd party inspections & verification

How Do You Deal With Mold?

Follow applicable building codesImplement BMPs appropriate for the macro and micro-environmentsInclude preventive I & M programs in terms of sales and leases

Identifying The Proximate Cause(s) of Mold Growth Related to Moisture Intrusion

We are better at identifying causation because we have:• Better understanding of why construction and installation

practices fail• Better understanding of how and why various

construction materials and products fail

Identifying The Proximate Cause(s) of Mold Growth Related to Moisture Intrusion

We are getting better at identifying causation because we have:

• Better understanding of how lack of maintenance contributes to failures

• Better equipment to detect failures

Infrared Thermography

Chronic Firewall Moisture (purple areas below white line)

Photograph 25: Firewall completed section. Note moisture profile.

Photograph 26: Firewall section opened. Note mold on fire resistant GWB. Inspection holes cut by contractor.

Infrared Thermography

Missing Insulation

Balcony Header Moisture

Infrared Thermography

Balcony Door Leak

Flashing Detail Brick to Roof

Flashing Detail at Balcony Headers

Balcony attachment to house. Note leak..

Interior leak in area of balcony. Note paint blistering and peeling.

Identifying The Proximate Cause(s) of Mold Growth Related to Moisture Intrusion

We are getting better at identifying causation because we have:

• Greater appreciation for rapid response with regards to water losses

• We are further along on the defects learning curve

What conditions promote mold growth?

• Moisture• Humidity• Temperature• Carbon• Oxygen• Time

• Water intrusion• Building defects• Design defects• Product defects• Maintenance• Occupant lifestyles• Catastrophic events• Ventilation; infiltration and

exfiltration

What building related factors What building related factors exacerbate mold growth?exacerbate mold growth?

• Condensation• Latent moisture• Vapor transport• Pressurization• Topography• Hydrostatic pressure• Drainage

What building related factors What building related factors exacerbate mold growth?exacerbate mold growth?

Moisture Intrusion-Wall Assembly

Latent MoistureDrainage ProblemsCapillarityThermal BridgingCondensationDefects allow Liquid Transport

DefectDefect

Convection (Stack Effect)and vapor transport

Air movement andvapor transport

Vapor pressureand diffusion

Moisture Intrusion-Pitched Roof Assembly

Defects allow Liquid TransportCondensation and Dew PointInadequate Ventilation

Potential for ice jams

DefectDryer venting not adequate

Blown-in insulationcovers bird screens

A bathroom fan exhausting into an attic crawlspace.A bathroom fan exhausting into an attic crawlspace.

Moisture Intrusion-Foundation Assembly

Latent Moisture from ConstructionPoor DrainageVapor PressureHydrostatic PressureCapillarityThermal BridgingCondensationDefects allow Liquid Transport

Defect

Faulty Vapor Barrier

Moisture Intrusion-Foundation Assembly

Stressed vegetation

Improper installation

Building Constructed on Filled WetlandPoor DrainageUnfavorable TopographySoils with low Permeability

Blocked or plugged foundation vents

Sump pump failure

Parking Lot

Dryer exhaust broken

Storm sewer

Bad Sump Pump

Moisture Intrusion-Foundation Assembly on Daylight Basement

Condensation and Dew PointHydrostatic PressurePoor DrainageVapor Pressure

Poorly conceiveddownspouts

Concrete foundationextends above soil levelSlab on grade

Parking Lot

SummaryWhat we just covered…

• Why some buildings fail by design• Why some construction and installation practices fail• How and why various construction materials and

products fail• How the lack of maintenance contributes to failures• Some new equipment in use to detect failures• Why rapid response to water losses is critical• Why we know more about predicting defects and

anticipating damaged conditions than we used to

For more information:Greg Baker, CIH, CSP, CHMM

AMEC Earth & Environmental, Inc.503 639 3400

www.amec.com