4/11/09 sustainable building advisor 1 smc national sustainable building advisor program designing...

4/11/094/11/09 Sustainable Building AdvisorSustainable Building Advisor 11

SMC National Sustainable Building SMC National Sustainable Building Advisor ProgramAdvisor Program

Designing Innovative Ventilation Designing Innovative Ventilation Systems for Good IAQSystems for Good IAQ

Richard ScarboroughRichard Scarborough

Environmental Inspections + SolutionsEnvironmental Inspections + Solutions

www.eisinc.cawww.eisinc.ca


Natural VentilationNatural Ventilation

What’s Happening?What’s Happening? When did it start?When did it start? How will it end?How will it end?

Back to the Basics

Breathe!


Global WarmingPer Goat and Mouse


Global Warming Conference


You Can Build it You Can Build it But Can you Ventilate it?But Can you Ventilate it?


There is no HopeThere is no HopeNew AnalysisNew Analysis

Pollution May Cause 40 Percent Pollution May Cause 40 Percent of Global Deathsof Global Deaths

By By Andrea Thompson, LiveScience , LiveScience Staff WriterStaff Writer

http://www.livescience.com/ posted: 10 September 2007 09:11 posted: 10 September 2007 09:11

AM ETAM ET


No Hope for No Hope for Healthy ConstructionHealthy Construction


Where I’ve LivedWhere I’ve LivedThe Dutch “Blow Through”The Dutch “Blow Through”


Where I’ve LivedWhere I’ve Lived


Where I Live NowWhere I Live Now


What I BuildWhat I BuildWhere it StartedWhere it Started


Thin Shelled Concrete StructureThin Shelled Concrete Structure

Thermal mass insideThermal mass inside Insulation outsideInsulation outside Performance = R60Performance = R60 10.0 earthquake proof10.0 earthquake proof Tornado proof / Bullet proofTornado proof / Bullet proof


What I Intend to Live InWhat I Intend to Live In


Jean Jean NouvelNouvel


Jean Nouvel Jean Nouvel LA Green CondoLA Green Condo


New ConstructionNew ConstructionEnergy ConservationEnergy Conservation


Back to the BreathBack to the Breath What Sucks ? What Sucks ?

Wind: Wind: • From high to low pressureFrom high to low pressure• You can’t push a ropeYou can’t push a rope

Tornados: big time!Tornados: big time! Houses: 99%Houses: 99% Humans: 100%Humans: 100%


22ndnd Law of Thermodynamics Law of Thermodynamics

Air moves from high to low pressureAir moves from high to low pressure• The bigger the hole, the more the pressure,The bigger the hole, the more the pressure, the greater the flowthe greater the flow

Moisture moves from:Moisture moves from:• Warm to CoolWarm to Cool• More to LessMore to Less• More to Less wins over Warm to CoolMore to Less wins over Warm to Cool

Implications for SoCalImplications for SoCal


Stack EffectStack Effect


Chimney EffectChimney Effect


Reverse Stack Effect?Reverse Stack Effect?

When?When? Where?Where? How?How? ImplicationsImplications


PressuresPressures

1 Pascal1 Pascal = 0.004 w.g = 0.004 w.g =0.000295”hg. = 0.000145 psi =0.000295”hg. = 0.000145 psi 9.8692×109.8692×10−6−6 atm atm

1 Pascal = 1 Post-it = 1 Gnat fart1 Pascal = 1 Post-it = 1 Gnat fart Combustion SafetyCombustion Safety

• Worst case scenarioWorst case scenario• The romantic eveningThe romantic evening

4 Pascals to backdraft a fireplace or 4 Pascals to backdraft a fireplace or water heaterwater heater



Design ConsiderationsDesign Considerations• SiteSite• Building MaterialsBuilding Materials• Prevailing windsPrevailing winds• ClimateClimate• Day lightingDay lighting• Operable windowsOperable windows



Knowledgeable & Tolerant usersKnowledgeable & Tolerant users Input source and locationInput source and location

• IH and EHIH and EH• Intake vs. exhaustsIntake vs. exhausts



Wind EffectWind Effect Venturi EffectVenturi Effect Cooling TowerCooling Tower


Displacement VentilationDisplacement Ventilation

Swamp CoolerSwamp Cooler


Cooling Tower


Downdraft cooling tower with evaporative media at top, exhaust through clerestory windows. Ref. WBDG

Zion National Park


Psychrometric ChartPsychrometric ChartFind the point of condensation


Vapor Diffusion

versus

Air Leakage

Moving Moisture

Where air goes water follows


Foundations / CrawlsFoundations / CrawlsWhere it all startsWhere it all starts

Codes arbitrary in creation of crawl Codes arbitrary in creation of crawl ventingventing

New Seismic concerns create New Seismic concerns create labyrinthslabyrinths

Passive ventilation can’t workPassive ventilation can’t work Mechanic ventilation has inherent Mechanic ventilation has inherent

problems.problems. Crawl should be mini conditioned Crawl should be mini conditioned

basementbasement


FoundationsFoundationsWhere it all startsWhere it all starts


CrawlsCrawls


Crawls Crawls


CrawlsCrawlsDisconnected Drier VentDisconnected Drier Vent


CleanSpace – Basement Systems


Chlordane, DDTChlordane, DDT What it did to meWhat it did to me Construction debris: mold foodConstruction debris: mold food Leaky HVAC ducting=pollution Leaky HVAC ducting=pollution

distribution systemdistribution system Self composting homesSelf composting homes

• Are they green?Are they green?

CrawlsCrawlsWhat We FindWhat We Find


What’s Wrong with this Picture?


Fresh Air DilutionFresh Air Dilution What’s your criteria?What’s your criteria?

• SmellSmell

• COCO22

• VOCVOC• TVOCTVOC• SVOCSVOC• OccupancyOccupancy• SeasonSeason


Fresh Air DilutionFresh Air Dilution

• COCO2 2 Sensor?Sensor?

• Formaldehyde levels even after heat Formaldehyde levels even after heat treatment do not begin to drop off in treatment do not begin to drop off in new home until after 2 yearsnew home until after 2 years

• How sensitive are the occupants?How sensitive are the occupants?• ACH-(air changes/hr) How real is it?ACH-(air changes/hr) How real is it?

With turbulent flow, 5 changes necessary for With turbulent flow, 5 changes necessary for complete dilution.complete dilution.

Circulation laminar channeling at bestCirculation laminar channeling at best


Fresh Air DilutionFresh Air Dilution

ASHRAE 62ASHRAE 62• Old: 0.35 ACHOld: 0.35 ACH• Politics as usualPolitics as usual• CFM per person/square footCFM per person/square foot• Office, commercial, residentialOffice, commercial, residential• Schools, laboratory, smoking roomSchools, laboratory, smoking room• How much is too much?How much is too much?


Air PathwaysAir Pathways

Typical wall airflow in stick frame house = Typical wall airflow in stick frame house = 6”/minute6”/minute

Where’s the air barrierWhere’s the air barrier Where are the penetrationsWhere are the penetrations

• ““Own your hole”Own your hole”• Pollutant pathways?Pollutant pathways?• CA Title 24CA Title 24

SVOC’s not easily sealed inSVOC’s not easily sealed in Does your home suck?Does your home suck? Stack / Reverse stack effectsStack / Reverse stack effects


Any air pathways?


Mechanical VentilationMechanical Ventilation

Push or Pull?Push or Pull? From where to whereFrom where to where Noise issuesNoise issues Velocity – draftiness, sensitivityVelocity – draftiness, sensitivity MixingMixing


Push me-Pull mePush me-Pull me


Got Leaks?


Multi-Task:dryer vent and water heater flue


Nike

“Just Do it!”


Supply Ventilation System Integrated with Heating and A/C


Pressure Differentials


Case StudyCase Study Pt. Dume Doom Pt. Dume Doom


Exhaust VentilationExhaust Ventilation

Bathroom exhaust fans: 60-150 cfmBathroom exhaust fans: 60-150 cfm Dryers: 200 cfmDryers: 200 cfm Kitchen exhaust: 100-2000cfmKitchen exhaust: 100-2000cfm With prudence, these can serve as With prudence, these can serve as

excellent whole house fansexcellent whole house fans


Total ExhaustTotal Exhaust

500-2500 CFM500-2500 CFM Big time suctionBig time suction


LEEDLEED

Make up your mind!Make up your mind! Underfloor designs – SMO libraryUnderfloor designs – SMO library VOC’s – VOC’s – Reformulated VOC’s = ?Reformulated VOC’s = ?

• Glycol based paints – the slow killGlycol based paints – the slow kill No concern for SVOC’sNo concern for SVOC’s


Winston ChurchillWinston Churchill

““You can always count on You can always count on Americans to do the right thing - Americans to do the right thing - after they've tried everything after they've tried everything else.”else.”

4/11/09 sustainable building advisor 1 smc national sustainable building advisor program designing...

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