Old Holloway straw passivhaus

  • Building Type : Isolated or semi-detached house
  • Construction Year : 2016
  • Delivery year : 2017
  • Address 1 - street : Old Holloway Cottage HR2 8BA LITTLE BIRCH, United Kingdom
  • Climate zone : [Cfb] Marine Mild Winter, warm summer, no dry season.

  • Net Floor Area : 95 m2
  • Construction/refurbishment cost : 150 000 €
  • Cost/m2 : 1578.95 €/m2

Proposed by :

Certifications :

  • Primary energy need :
    89 kWhpe/m2.year
    (Calculation method : Primary energy needs )
Energy consumption
Economical buildingBuilding
< 50A
A
51 à 90B
B
91 à 150C
C
151 à 230D
D
231 à 330E
E
331 à 450F
F
> 450G
G
Energy-intensive building

Old Holloway is a private single family house in rural Herefordshire. It's a simple, modest, single storey dwelling with pitched roof and south facing verandah, sympathetic to local vernacular architecture. 

Old Holloway was the first UK application of Ecococon timber/ straw prefabricated panel system (also a passivhaus certified component). Prefabrication allowed for rapid and accurate construction (example: external walls were erected in three days and the whole house watertight in four weeks). Simple and robust detailing and airtightness strategies, suitable for self-build construction, were adopted. Ecococon system provides a healthy, high performing construction system, with very low environmental impact.

Old Holloway was the Small Projects winner at 2018 Passivhaus Trust Awards and runner-up at 2019 ASBP Awards

See more details about this project

 https://oldholloway.wordpress.com
 https://passivehouseplus.ie/magazine/new-build/deep-green-passive-house-defies-all-weather
 https://www.treehugger.com/old-holloway-passive-house-all-about-comfort-and-luxury-4855053
 https://www.passivhaustrust.org.uk/projects/detail/?cId=88

Data reliability

3rd part certified

Photo credit

Juraj Mikurcik

Contractor

    Mike Whitfield Construction Ltd

    Mike Whitfield

Construction Manager

    Juraj Mikurcik

    Juraj Mikurcik

Stakeholders

    Designer

    Juraj Mikurcik

Contracting method

Other methods

Owner approach of sustainability

Our aim was to live in a modest, affordable and healthy home. We wanted to build with biobased materials as far as possible. This is our first 'self build' project, it was a great experience getting directly involved in commissioning, design, project management and some of the construction of our house. 

Architectural description

The dwelling has a flexible layout, it can be used as a two bedroom house plus office or a three bedroom house. Central open plan living room/ kitchen/ dining has a direct access to external decking via a large sliding door.

Open cathedral ceilings provide a sense of generous internal space with small external impact. Extended roof overhang to south (verandah) provides shelter and useful summer shading. Windows are optimised for views and daylighting. Corrugated metal roof and locally sourced charred cedar cladding are the two key external finishes.

Old Holloway is the first UK application of Ecococon timber/ straw prefabricated panel system (also a passivhaus certified component). Prefabrication allowed for rapid and accurate construction (example: external walls were erected in three days and the whole house watertight in four weeks). Simple and robust detailing and airtightness strategies, suitable for self-build construction, were adopted. Ecococon system provides a healthy, high performing construction system, with very low environmental impact.

Key materials and finishes
Exposed ground and sealed concrete slab
Self-finished clay plaster walls (no paints applied)
Timber cladding: local cedar charred on site
Corrugated metal roofing – local and very economical

If you had to do it again?

If we did the project again, we would give further consideration to the choice of material for foundations. The embodied carbon in concrete is high and there are some good alternatives available. We would also probably not install the wood stove, as we don't really use it very often, the capital could instead be spent on renewable technologies such as PV panels.

Building users opinion

The house has been a delight to live in since it was completed nearly 4 years ago. It it really easy to live with and a contrast to the previous home, which was uninsulated stone cottage. Being a passivhaus the energy demand for heating is very small. At the same time, the quality of internal air is excellent all year round thanks to the central ventilation system with heat recovery (there's automatic summer bypass). CO2 levels generally stay below 800ppm and air 'feels' fresh due to minimum amount of VOCs in the interior. Temperature is very stable, during winter it goes down to about 18C and never goes above 25C in summer, even during the heatwaves. Internal relative humidity is between 40-60%. The house is well daylit, generally there is no need to put the lights on during the day. Acoustics are excellent, will low levels of reverberation thanks to hit & miss batten ceiling in the main living space. Textured clay plasters on walls also help reduce the echo effect.

Energy consumption

  • 89,00 kWhpe/m2.year
  • 89,00 kWhpe/m2.year
  • Primary energy needs

  • 89,00 kWhfe/m2.year
  • Primary energy needs corresponds to Passivhaus PE value.

    heating approximately 1200kWh/a
    hot water approximately 2400kWh/
    acooling:
    zeroventilation: approximately 200kWh/
    alighting & other small power: approximately 900kWh/a

    monthly average electricity bill approximately 80 Euro (this covers everything)

Envelope performance

  • 0,13 W.m-2.K-1
  • External walls consist of 400mm thick Ecococon prefabricated straw/ timber panels, externally clad with 60mm woodfibre board and ventilated timber rainscreen cladding. Internally the walls are plastered with 25mm clay plasters, adding useful thermal mass. Floor is exposed concrete slab, fully insulated under. This also adds useful thermal mass helping to slow the daily temperature swings. Floor u-value 0.135W/m2K. Roof is 400mm timber I-beams fully insulated with blown recycled cellulose insulation, u-value 0.093W/m2K. Corrugated steel roofing finish. Windows are triple glazed timber/ aluminium composite, passivhaus certified u-value 0.83W/m2K

  • 4,60
  • EN 13829 - n50 » (en 1/h-1)

  • 0,40
  •  Blower door test

    The heating system consists of two towel rails running off the ASHP hot water cylinder, and a standalone wood stove. Towel rails are running off a pump with three modes (off, auto and 100%). 

Real final energy consumption

    47,00

    2 020

Systems

    • Heat pump
    • Wood boiler
    • Heat pump
    • No cooling system
    • Double flow heat exchanger
    • No renewable energy systems
  • 75,00 %
  • High performance triple glazing allow solar gains whilst keeping the heat in during winter. In summer, the glazing is mainly shaded with roof overhang and external blinds, preventing unwanted solar gains and overheating.

GHG emissions

  • 16,50 KgCO2/m2/year
  • PHPP

  • 100,00 year(s)

Water management

  • 110,00 m3

Indoor Air quality

    Generally building materials and product with low VOCs have been used: timber and straw wall panels, self-finished clay plasters, low VOC paints and stains. Central ventilation system ensures the air is changed at the rate of 0.4 per hour.

Health & Comfort

    between 450 and 800ppm CO2

    indoor temperatures vary between 18C (coldest point in winter) and 25C (peak summer heatwave)

Product

    EcoCocon

    Ecococon

    info@ecococon.eu

    Structural work / Structure - Masonry - Facade

    Prefabricated straw/ timber panel system. Highly efficient, it is a certified passivhaus component, also has Cradle to Cradle certification. Approximate cost 150 Euro/m2 of wall

    Very enthusiastic about the product, it was the first application of the system in UK

Construction and exploitation costs

  • 3 000
  • 150 000

Energy bill

  • 960,00

Urban environment

Plot is at the end of existing village. There is a bus stop nearby, connecting the village to the nearest town of Hereford. Plot is also within cycling distance to place of work and the nearest town.

Land plot area

1 350,00 m2

Built-up area

8,00 %

Green space

1 000,00

Parking spaces

Private drive with flexible parking spaces (1 car in the household only)

Building Environmental Quality

  • indoor air quality and health
  • comfort (visual, olfactive, thermal)
  • energy efficiency
  • building end of life management
  • building process
  • products and materials

Health & Comfort: the building uses materials which are predominantly biobased, such as timber, straw and clay plasters. Most of internal walls are unpainted self finished clay plaster. Low VOC paints have been used for some ceilings. Mechanical ventilation with heat recovery maintains an excellent indoor air quality whilst minimising heat loss in winter. 

Energy & Temperate climates: passivhaus certification means the house has very small heating demand, monitoring over the last 4 years confirmed average space heating demand of approximately 12kWh/m2.a. Overall annual electricity consumption is approximately 4500kWh

Low carbon: the house is built predominantly with low carbon materials such as timber, straw, recycled cellulose and clay. Ecococon prefabricated straw panel system is Cradle to Cradle certified. 

Contest categories

Energy & Temperate Climates

Energy & Temperate Climates

Low Carbon

Low Carbon

Health & Comfort

Health & Comfort

Green Solutions Awards 2020-2021

 straw
 passivhaus
 health and comfort
 biobased
 offsite

Author of the page


  • Other case studies

    More

    Contest

    Green Solutions Awards 2020-2021