Scaling Up Passivhaus THE CENTRE TRE FOR MEDIC ICINE, INE, UNIVER - - PowerPoint PPT Presentation

THE CENTRE TRE FOR MEDIC ICINE, INE, UNIVER VERSITY SITY OF LEICES ICESTER TER

Scaling Up Passivhaus

Jon Chadwick

Pre redic icte ted d Per erfo form rmance ance

U-values: Walls 0.13W/m²/k Roof 0.13W/m²/k Floor 0.13W/m²/k Airtightness: 1m³/m²/hr @ 50Pa Equates to: 0.33 ac/h

The Design n Team

Project Managers Architect and Lead Consultant M+E Engineers Passivhaus Designers Structural and Civil Engineers Cost Consultants Project Managers Cost Consultants Technical Advisor Main Contractor Passivhaus Designers Architect and Lead Consultant Structural and Civil Engineers Passivhaus Consultants Pre e Cont ntrac ract Post st Contract tract Client ent Client’s Retained Consultants Design Advisor Contractor’s Design Team M+E Subcontractor

An Overview iew of the 2011 Client nt Brief: ef:

• Bring together the Schools of Medicine, Health Sciences and Psychology
• Adjacent to the existing medical building
• Sensitive to context – ecology and heritage
• Contribute towards reducing the University’s carbon footprint – passive design
• Allow the existing building to be upgraded in the future
• 13,000sqm of teaching, research and support spaces for 2,400 occupants
• Range of flexible teaching spaces with potential for conference use
• Deliver the building by September 2015

Background Site Information – Regent College Site

• Locally listed building (Regent College)
• ‘Conservation Area’ and listed ‘Fire Station Cottages’
• Protected trees on site boundary
• Protected views towards the War Memorial
• Risk of overshadowing adjacent buildings
• Loss of open space & playing fields
• Ecological impact
• Concerns over car parking provision
• Bomb shelter & potential archaeology
• Demolish bomb shelter - provide new football pitch
• Increase site biodiversity
• Respect Regent College
• Face the University and mark the start of the campus
• Provide an efficient plan form
• Maximise passive measures

Planning nning Issue ues Design ign Approach roach

1. 2. 3. 4.

Finger Blocks Rotate 45 Degrees Aligned to South & College Façade Respond to Sun

• Square block responds

to site boundaries.

• Split block up allowing

views through into site.

• Narrow floor plate to

max daylight.

• Landscape planted

through building gaps.

• Stepped heights of

blocks high to Uni Rd.

• Rotate blocks to

face directly south.

• Orientation best

to control solar gain.

• Building faces the

corner legible entrance!

• Blocks turn back on

College grid into site responding to context.

• Rotation provides a

pedestrian arrival space and separate service zone.

• Prickly façade

animates building protection from solar gain.

Concept – Plan Form

High Level View from the Roof of MSB

MSB Colle ge

Proposed Sports Hall

MS B Colle ge

Proposed Sports Hall

Plan Development

Proposed Site Layout

Regent College Proposed Site Re-located Football Pitch Future Extension Lancaster Road MSB

Environmental Strategy for Academic Office spaces

Borrowed light through partition walls Borrowed light through partition walls High level glazing maximises light into rooms High level glazing maximises light into rooms Mech venting air input and heat recovery Mech venting air input and heat recovery Some shading by building structure Shading by external blinds

Lab Space 1P Office 1P Office 1P Office Multi-Occupancy Office

Green en Roof f / Brown Roof Green en Wall PV Panel els GAHE Labyrint rinth Efficient nt AHUs s with Heat t Recover

• very

(distribution across roof and below ground within insulated service ducts) Fixed Brise Soleil eil Highl hly insulat ated ed cavity wall to lower floors PH certified ed curtain n walling Exposed sed thermal al mass s in P PT frame and wall Façade ade - insulated ated precast ast concr crete ete sandw dwich ch panel nels Active external rnal shading ading blinds ds Shal allow

• w floor plates

s for natur ural al ventilation ation Glazed ed screens ens for borrowed

• wed light

Roofli flight ghts with externa nal shadi ding ng District t heating ng

Tender er Stage ge – Enviro ironmen nmental tal Proposals posals

Plant t rooms s outside side Passiv sivhaus haus ‘TFA’ Embedded edded TABS soffit cooling ng and d UFH to atria

Building Cross Section

GAHE Labyrint rinth h (change to vent towers) Efficient nt AHUs s with Heat t Recover

• very

(distribution within ceiling voids of occupied floors only) Highl hly insulat ated ed cavity wall to lower floors Full curtain n walling with brick slip panel nels (concrete backing panels for thermal mass))

Contractor’s Proposals – Enviro ironmen nmental tal Proposals

• posals

Plant t rooms s brought ught inside e Passiv sivhaus haus ‘TFA’ Change nged d to insulat ated ed render der Active external rnal shading ading blinds ds (continuous blind box detail as part

• f curtain wall façade)

Change nges to Façade ade Const struc ruction tion – Upper per Floors rs

• Unitised curtain walling windows between precast brick slip clad panels
• Air seals on all four sides
• Opening vent panel behind fixed louvre
• Individual blind box for each window
• Thermal mass

Tender der: : Precast ast Concr cret ete e Sandw ndwich ch Panel nel CPs: Full Curtain n Walling g with Brick Slips

• Full curtain walling façade – storey height screens
• Brick slip panels fixed to insulated metal panels
• Reduced requirements air seals
• Opening vent panel behind fixed louvre
• Continuous blind box around slab perimeter
• Thermal mass replaced by non-structural infill

Change nges to Façade ade Const struc ruction tion – Upper per Floors rs

• Single subcontractor responsibility
• Easier construction
• Faster programme
• Tighter tolerances

Pros: : Tender der: : Precast ast Concr cret ete e Sandw ndwich ch Panel nel CPs: Full Curtain n Walling g with Brick Slips

Change nges to Façade ade Const struc ruction tion – Upper per Floors rs

• Planning risk
• Additional movement joints
• Risk of interstitial condensation
• Additional seals / VCLs required
• Overall façade zone increased ~150mm
• Greater coordination with PT frame

Cons: s: Tender der: : Precast ast Concr cret ete e Sandw ndwich ch Panel nel CPs: Full Curtain Walling with Brick Slips

External nal Shadi ding ng Blinds

• CTB blinds - not used before in UK
• UoL nervousness about maintenance
• Automatic operation – linked to BMS
• Automatically retract in high winds
• Tender design - small sections
• Contract - continuous ‘ribbon’
• Blind box - thermal weak link

Façade ade Const nstruct uction

• n – Lower

er Floors

Façade ade Mock ck-up up Panel el

Façade ade Mock ck-Up p Panel nel

Tender er: Roof top plant rooms outside thermal envelope Basement plant room inside the thermal envelope Contract ract: All plant rooms inside thermal envelope Increased ‘Treated Floor Area’ Ventilation duct runs – inside thermal envelope Simplification of scheme Thermal al Envelope

• pe

Cold Duct t Runs ns

• Extensive cold duct runs within envelope
• Plant room layouts changed to minimise cold duct runs
• Suitable AHUs – not available as PH certified products

Thermal al Bridging ng

• Minimising thermal bridging is crucial
• Couldn’t all be eradicated or calculated prior to contract
• Schedule of thermal bridges compiled
• WDES did thermal modelling
• Pile caps insulated on all sides, piles not insulated
• Thermal pads included on all steelwork connections
• GRC cladding changed to insulated render

Ground-Ai Air r Heat Exchan anger ger

• Redesigned to ease construction
• GAHE located beneath the building
• Extensive coordination – design period increased
• Vent towers integrated into ‘dummy’ columns
• Verifying the efficiency of the system to suit PHI
• Very deep excavations
• Installation took longer than anticipated

17 April 2014 21 May 2014

08 Septembe tember 2014

Conclusi usions

• ns
• On track - September 2015 and Passivhaus certification
• Difficulties sourcing products to suit the aesthetic
• Lack of Passivhaus knowledge and experience amongst contractors
• PHPP proved a useful design tool
• Effective communication of key design requirements - ?
• Site supervision - ?
• Increased capital costs for Passivhaus have fallen
• Achieving DEC A will be a challenge