karen rollins: sustainable mountain accommodation – bees

Sustainable Cold Climate Construction

Karen RollinsSustainable Summits Conference 2016

Aoraki Mount Cook National Park New Zealand

Cold Climate Construction

Alpine Construction

Sustainable Construction

Introduction

Cold Climate

Subarctic/arctic>12,600 heating degree days

Very Cold>9,000 heating degree days

Cold>5,400 heating degree days

SNOW ZONE

ALPINE

SUBALPINE

MONTANE

FOOTHILLS

Polar Desert

Cold Climate Construction

A. Cold Temperatures(How cold affects design and operation of buildings)

Two design strategies for cold climates:

B. Heat Loss ControlC. Moisture Control

A. Cold TemperaturesChallenges:• Frozen precipitation

(snow, frost, hoarfrost, permafrost, spindrift, drifting snow, ice)

• Extreme temperature shifts

• Wind, wind‐driven rain (DRWP)

• Freeze/thaw cycles• UV radiation• Maintenance (remote)

Design Considerations:• Robust building materials and

mechanical systems– Don’t crack in cold T– Expansion and contraction

• Roof designed for snow load• Structural strength (wind pressure)• Special design for building

envelopes to accommodate all seasons

• Backup & redundancy

Spindrift and Snowdrift

• Mountain climber: Loose powdery snow incapable of holding protection

• Engineer: Fine wind borne snow capable of entering a building through any opening in the building envelope

B. Heat Loss Control

Overall heat loss control strategy:1. Control thermal building envelope

– Heat Loss mechanisms• Conduction• Convection• Radiation

2. Control air leakage

1. Control Thermal Envelope

1965 1980 1985 1990 Passive House

Heat Loss Through Conduction

Thermal Bridge

Dust Marks

Solutions for Thermal Bridging

2. Control Air Leakage

Solutions for Air Leakage

AIR BARRIER• impermeable to air flow• continuous over the entire building enclosure• able to withstand forces during and after construction

• durable over the lifespan of the building

Solutions for Air Leakage

Ice Damming

COLDER AREA

WARMER AREA

4. WATER GETS TRAPPED AND BACKS UP UNDER SHINGLES

1. HEAT LOSS

2. UNDERSIDE OF ROOF IS WARMED AND MELTS SNOW

3. WATER FREEZES AT EAVES AND FORMS ICE DAM AND ICICLES

Causes water damage in the attic

Solutions for Ice Damming

Continuous air barrierInsulationVentilationHeat tape

SOFFIT VENT

GABLE VENT

RIDGE VENT

ROOF VENT

Insulation VentilationEave ProtectionHeat tape

Water Shield

C. Moisture Control

Overall Moisture Control Strategy:• In cold climates the goal is to make it as difficult as possible for the building assemblies to get wet from the interior.

• In cold climates building assemblies dry towards the exterior, therefore permeable (breathable) materials are specified as exterior sheathings.

Condensation

a) Increase condensing surface temperatureb) Vapour barrier to keep moisture out of wallsc) Ventilation to remove moistured) Source control

Strategies to Control Condensation

a) Increase Condensing Surface Temperature

Inside +20C

Outside ‐20C

b) Vapour Barrier

• 6 mil polyethylene installed on warm side of insulation

• Continuous, all joints and penetrations sealed

Inside +20C

Outside ‐20C

c) Ventilation to Remove Moisture

Heat Recovery Ventilator

d) Source Control

EXHAUST

WARM AIR RISES

AIR INTAKE

Sustainable Construction

Increase EfficiencyIncrease Efficiency

Energy

Water

Building Materials

Reduce ImpactReduce Impact

Environment

Human Health

Life‐cycleLife‐cycle

DesignBuild

Maintenance Demolition

…Striving towards

Priorities

• People priorities– Health and safety– Comfort– Affordability

• Building priorities– Durability– Renovation– Decommissioning

• Environmental priorities– Local, regional, global environment

Features of Sustainable Construction

• Preserve natural vegetation on site• Rain water collection• Reduce construction waste• Recycled, durable, local building materials• Efficient furnace• Reduce heat loss through building envelope (insulation and air sealing)

• Renewable energy, reduced use of fossil fuels• IAQ plan, reduced air pollution, low VOC

Most Sustainable Structure

Local building materials (zero transportation costs)Recyclable building materialsDurable materialsZero G.H.G. to manufacture building materialsZero environmental impact (local, regional, global)Easy to decommissionAffordable

Alpine Construction

Design Challenges:• Off‐grid• Remote• Extreme low temperatures• Extreme wind• Snowfall, drifting snow, spindrift• Moisture producing activities• No live in custodian (easy to operate technologies)• Periodic use (thermal conditions not steady) • National Parks location (building restrictions)

Guy Hut at Mount Des Poilus


Wapta Icefields near Mount Des Poilus (2580m, 54°L)Alpine Club of Canada (owner, general contractor)BEES (design criteria and building specifications)Architect: Greg JablonskiTeam: structural engineer, mechanical engineer,

environmental assessment, alternate energy designer,surveyor, weather study, SIP manufacturer, propane plumber, helicopter, many volunteers

Build a structure that enhances visitor experience and acts as a model for other off‐grid facilities

Vision

• Environmental integrity• Advanced construction methods and materials: sustainable construction features

• Reliable and easy to operate technologies • Energy efficient • Healthy indoor environment

Design Goals

!

Vision Build!a!structure!

that!enhances!visitor!experience!and!acts!as!a!model!for!other!off6grid!mountain!facili8es!around!the!

world!

Goal Advanced!

construc8on!methods!and!materials!

Goal Superior!Energy!

Effic

i

ency!

Goal Easy!to!operate!and!maintain!technologies!

Goal Excellent!indoor!air!

quality!

Goal Environmental!Integrity!

Structural!Insulated!Panels!

Reduced!thermal!bridging!

Boiling!snowmelt!to!treat!potable!

water!


Super!insulated:!Passive!House!

Standard!



Solar/wind!hybrid!

renewable!energy!system!

Greywater!dispersion!

field!

Barrel!fly6out!system!

Propane!stove!

Solar/wind!hybrid!


Propane!stove!

Heat!recovery!ventilation!!


Heat!recovery!ventilation!

Recycled!content!building!materials!


Standard!


Standard!


Standard!

Reduced!site!

disturbance!

Low!VOC!emitting!building!materials!

Daylight!and!views!

Moisture!control!

strategies!

Indoor!environmental!monitoring!!

Barrel!fly6out!system!

Grey6water!dispersion!

field!

Heat!recovery!ventilation!!


Propane!stove!

Solar/wind!hybrid!



Moisture!control!

strategies!

Recycled!content!building!materials!

• Considerations for ecological integrity – winter use, 700/yr. • Greywater treatment: dispersion field• Low visual impact, small footprint• Construction waste management, recycled building materials (flooring), durable building materials, locally manufactured building materials, low VOC materials (paint, caulking)

• Energy efficient building envelope• Heat primarily from the sun (80‐90%)• Propane (burns cleanly) for cooking, lighting, heating• Renewable energy system: solar and wind (lighting, ventilation)

• Human waste removed from the site

Sustainable Construction Features

• Well‐insulated thermal building envelope• Reduced thermal bridging• Air tight construction: air barrier, vapour barrier• Heat and ventilation to prevent condensation• Covered front entrance and air lock entry• Technologies are easy to operate and maintain• Redundancy in lighting and heating and ventilation

• Moisture control strategies

Cold Climate Construction Features

Moisture Control Strategies

• Heat• Ventilation• Super‐insulation• Minimal thermal bridging• Keep furnishings (kitchen cabinets, sleeping bunks) away from exterior walls

• Drying room for wet gear to isolate moisture from the rest of the hut (ventilated)

Well‐insulated

R‐16 R‐24 R‐24 R‐32 R‐45 R‐50

Passive House

1965 1985 20051988 Bow Hut

2014 Des Poilus Hut

Structural Insulated Panels (SIPs)

• Walls, floor, roof• Structural framing, insulation,

air barrier, vapour barrier • Short assembly time• Strong• High insulating value• Air‐tight• Reduced thermal bridging• Moisture control• Fire resistant

Healthy Indoor Environment

• Temperature control – high quality thermal envelope, air lock entry, heat source (sun and propane stove)

• Ventilation– Kitchen, bedroom, drying room exhaust– Fresh air warmed by propane stove

• Moisture control to prevent condensation and mould• Propane instead of wood burning ‐ particulates• Layout designed by an architect• Day lighting & views• Low VOC building materials

• Alpine construction can feature sustainable construction and cold climate construction

• Cold climate during construction can play a significant role

Conclusions

• Cold Climate Housing Research Centre –Fairbanks Alaska

• ASHRAE: Cold‐Climate Buildings Design Guide• Builder’s Guide to Cold Climates – Joseph Lstiburek

• Canadian Center for Housing Technology• CMHC Canadian Wood‐Frame House Construction

Resources

Thank YOU!