Pitched Internally Fitted

The system complies with the most stringent of standards – from baseline building regulations through to Passivhaus.

The system is suitable for most internal finishing options, including lime plaster, clay plaster or plaster board finish. All components for the system are available from Unity Lime.

CROSS SECTION OF SYSTEM

  1. Existing tiles/slates
  2. Existing non-breathable felt
  3. New treated timber battens (min. 45mm height), fixed to existing rafters to create ventilation area
  4. System glue (to seal battens to rafters and woodfibre boards to battens
  5. ISOLAIR. Option A: fixed to the battens. Option B: fixed to the rafter.
  6. PAVAFLEX or PAVATEXTIL-P between battens. Option A: DB 3.5 airtightness membrane can be installed after this layer
  7. ISOLAIR
  8. a) Lime-based plaster system. b) DB 3.5 airtightness membrane; service void and plasterboard

SYSTEM PERFORMANCE

u-values
0.30 – 0.10

y-values
0.05 – 0.02

Airtightness
5 – 0.6 @50pa

COMPONENTS AND ACCESSORIES FOR PITCHED INTERNALLY FITTED

PRODUCT DOWNLOADS

Build up Options-IRI UNDER RAFTER

Build up Options-IRI BETWEEN RAFTER

Retrofit Roof Pitched Internally Fitted System Sheet