fbpx

Technical Information

Dimensions of Green Unit ARC I and ARC II modular buildings

ARC I 
  • Internal floor width 4.0m
  • Internal height 2.4m at highest point
  • Internal width 4.8m at widest point
  • External footprint width 4.5m
  • External width at widest point 5.4m
  • External overall height 3.2m
  • External height with floor at ground level 2.7m (foundation base 0.5m below ground level) 

ARC II 

  • Internal floor width 6.4m
  • Internal height 2.4m at highest point
  • Internal width 7.2m at widest point
  • External footprint width 6.6m
  • External width at widest point 7.8m
  • External overall height 3.2m
  • External height with floor at ground level 2.7m (foundation base 0.5m below ground level) 

Find out more about our offsite construction build process, and watch a timelapse of our ARC II for The Vindolanda Trust. 

Materials used in design and build of ARC I and ARC II

  • Spruce and birch plywood structure
  • Wood fibre insulation
  • Breathable external membrane
  • Airtight, vapour control (internal membrane) with fully taped joints
  • Triple glazed units
  • High-performance airtight triple glazed windows (vented or unvented, as required)
  • High-performance airtight triple glazed exterior doors (vented or unvented, as required)
  • Internal cladding - painted solid timber (other options available, to be determined during design consultation) 
  • External cladding - thermally modified, sustainable UK poplar (other options available, to be determined during design consultation) 
  • Water-based acrylic paints and lacquers
  • Solvent-free adhesives
  • Powder-coated aluminium cladding and window flashings
  • Painted timber end fascia boards
  • Water and root-proof roofing membrane
  • Sedum green roof

Technical specification of the Green Unit ARC 

 

Current UK regulations
(for non-dwellings)

Passivhaus requirements

Standard building

Green Unit

Floor insulation

0.25W/m²K

<0.15W/m²K

0.22W/m²K

0.18W/m²K

Wall insulation

0.35W/m²K

0.15W/m²K

0.3W/m²K

0.16W/m²K

Roof insulation

0.25W/m²K

0.12W/m²K

0.24W/m²K

0.16W/m²K

Airtightness

10m³/hr/m²

0.6m³/hr/m²

10+ m³/hr/m²

2m³/hr/m²

Air changes per hour

10ach

0.6ach

7ach

variable to 10ach

Air quality

Medium

High, filtered

Medium

High, filtered

Embodied energy

Not measured

Minimum possible

129 – 239 kW/m²

81 kW/m²

Recyclability

No requirement

Encouraged

Low recyclability

Fully recyclable

Testing procedure

SAP

Physical test

SAP

Physical test

 
Notes:
- See further information including information about U Values in Building Regulations Part L2A (non dwellings) on the Planning Portal (external link).
- See further information about Passivhaus requirements (external link).