Portlaoise Train Drivers Facility Building – Key Points

First Passivhaus Building

For any Railway Company in the World

First Certified Non Residential Passivhaus

For State or Semi state sector in Ireland

Passivhaus principles developed with Sustainable Design principles and materials

Design for Deconstruction

Formed a key part of the approach to detailing

David Hughes B. Arch., C.P.M.A. M.R.I.A.I., R.I.B.A.

David Abbey BSc. (Hons) Arch. Tech. R.I.A.I. (Arch. Tech.)

david.hughes@irishrail.ie

david.abbey@irishrail.ie

Why Passivhaus?

Journey Towards Passivhaus Standard

• Interest in Low Energy Design from Undergraduate Days

• Looked at Different Low Energy Design Tools

Carbon Trust LT Method,

Ecotect,

Energy Plus etc.

• Has previously designed an Energy Zero and Carbon Zero railway station

• Pareto Principle or 80:20 Rule

Rules of Thumb in Passivhaus Planning Package How many here could size the power output required for say a 200 sq m building in their head?

Well maximum heat load per sq m allowed is 15W so

200 sq m x 15 W is 3000W or 3kW.

Not many architects were able to do that before the PHPP!

Similarly Clients know

Maximum energy demand will be 120 kWh/sq m/yr

This is very simple and clear cut

Can specify in confidence that once certified building will achieve this

Very good correlation between PHPP predictions and building use in practice measure over 18 years now.

Complementary Studies

HygroThermal Analysis

WUFI

Thermal Bridge Analysis

Therm 5.0

PHPP Led Design Concept

Concept Internal Layout Concept Roof Light Design

Developed Design

‘My Favorite Detail’ …Thermal Bridge!

Strip footing with stub columns Superstructure Separated Thermally

‘Construction Type’ Double Studded Timber Frame Suspended Floor

Floor Filled with Cellulose Insulation A lot of Cellulose Insulation!

Hygrothermal Design

Traditional Wall Modern Wall

Aesthetics and Performance

Natural Granite Rainscreen Cladding

Rainscreen eliminates the 70% wind driven rain normally absorbed

Daylight Design

• Thermal Comfort 17.8 deg C

• Low Thermal Transmission 0.6 W/m2 K

• Good light transmittance g value

• But detailing is the key

Designing for Air Tightness

Designing for Airtightness Getting the basics Right Thinking of the Test Day as well

Some Construction Images…

Avoiding Penetrations Complex geometry behind air tight layers

Favourite Materials Sustainable Materials and Design for Deconstruction

Cellulose Insulation Sustainable Materials also include

GGBS Concrete for Strip Footing

Steel

Timber sections and sheets all from FSC sources

All materials are screw fixed or bolted to allow for non destructive deconstruction

Sustainable Materials and Design for Deconstruction

External Stone Cladding Natural Granite which is the most abundant stone in the world.

All stone panels are identical except for corners and windows.

All stone is dry mounted using a self supporting and demountable stainless steel system outside the thermal and windtight envelope.

Interior finished with

‘Fresh Air Paint’ which ensures good indoor air quality and helps break down any formaldehyde ions off gased by OSB boarding.

The Kit Renewable and Green Technologies

Rainwater Harvesting Solar Thermal

Compact Unit MHRV Hotwater

Heat Pump

Occupiers Impressions

What is Next...Would I do it again? Environmental Rating Schemes

• The Passivhaus Sets a standard of no more than 120kWhr/sq m per yr of Primary Energy (i.e. energy at the power station)

• • Our building is within this currently around 108kWh/sq m yr • • The passivhaus institute state wall u values should be no more than 0.15W/sqm K • • Ours are about 0.07 W/sq m K so about half of a very low standard already. • • Air tightness again Passivhaus states 0.6 ours is 0.3 again half of a very low standard already. • • Our biggest demands are hot water and we are providing this using solar thermal energy. • • We used recycled newspapers (waste source diverted from trains) to insulate the building. • • All timbers are FSC certified. • • All paint is Freshair paint no VOCs • • Finishes such as floor finish are lino natural linseed oil based product and granite. • • Granite was chosen as it is the most abundant stone in the world. • • All granite panels are dry and open jointed • • Rainwater harvested would provide for about 50% of water usage. • • The rest is potable water from the local mains as it was on site and not feasible to set up a

different system of filtration on site.

The Living Building Challenge 2.0 Imagine a building designed and constructed to function as elegantly and efficiently as a flower: a building informed by its bioregion’s characteristics, and that generates all of its own energy with renewable resources, captures and treats all of its water, and operates efficiently and for maximum beauty. Imagine a city block or a college campus sharing resources from building to building, growing food, and functioning without a dependency on fossil fuel-based transportation. Imagine true sustainability in our homes, workplaces, neighbourhoods, villages, towns and cities – Socially Just, Culturally Rich and Ecologically Benign TM.