Case Study

PIHA HOUSE

piha - west auckland

Motivation & Brief

The original brief was to add a new kitchen and bathroom, upgrade the window joinery, add a guest bedroom and overall improve the thermal performance by increasing insulation and air tightness.

Renovate Existing Building

This was actually quite a recentely build house. An all concrete house, built in 2008

House Size

345sqm of floor area plus 70sqm of concrete terraces.
2 Storey, 3 Bedroom, 2 Bathroom

Property Site Information

Site Area: 8391sm
Elevated 104m above sea level
Very High Wind Zone
Faces West & Northwest
Sea Spray Zone

Zone: Residential – Rural & Coastal settlement
Natural Heritage: WaitakereRanges Heritage Area Overlay
Natural Resources: Significant Ecological Areas Overlay

Hidden Unplanned Issues

As we got into the project we discovered things during the demolition including quite extensive mould behind all the linings and inside the ceiling spacing and at that point it was decided to undertake a full renovation that of a passive house EnerPHit. This was mainly driven by the owner due to ongoing personal health issues resulting of years of exposure to damp moulding housing conditions.

Project duration

Start Date : MAY 2019
Completion Date: FEB 2022

Design Specification - Existing vs Renovated

Existing House - Built 2008

Concrete block walls
Ground Slab
Suspended Mid Floor Slab & Terraces
Aluminium Standard windows ( non thermally broken with single glazing
Minimal internal Insulation – 25mm EPS polystyrene on the inside and Batts in the ceiling
Butynol membrane cold roof
Plaster system Cladding

Renovated House 2021

Retained existing concrete structure
Replaced Windows with… SEDA Windows high performance timber -Alumium Windows low g-valve double glazing
Stotherm exernal insulation plaster system
Nuraply warm roof – two layer insulation
New Kitchen & Bathrooms
Edge innovation Wolf MHRV + Dehumidifier
Solar PV and Battery storage Solar DHW Boost
Renovate Water tank and Bore
Opening Louvre roof and screens to west deck

Floor Plans

Ground Floor Plan

Second Storey Floor Plan

Project Team

Architect – Sang Architets
Structural Engineers – Richards Consulting Engineers
Certified Passive House Designer – Sustainable Engineering
Main Contractor – Bruyere Passive Homes
Windows – Seda Windows
Cladding – Stotherm Installed by Plaster Solutions
Warm Roof – Nutralite Warm Roof
MHRV incl Dehumidification – Wolf System from Edge Innovation
DHW Hot Water Heat Pump – Edge Innovation
Solar PV & Solar Hot Water – Solar King
Electrical – Maximum Power
Plumbing – R & L Plumbing
Louvre Roof – Johnson & Cousins
Glass Balustrades & Screens – Viridian Glass/ Euro Glass