What type of insulation, and why?

[admin]

Thanks for the link – I will check this out.😀

[David]

Extract from the report in Passive House Plus: https://passivehouseplus.co.uk/magazine/new-build/stirling-work-the-passive-social-housing-scheme-that-won-british-architecture-s-top-award

“Passive-grade timber frame

All homes are bright and spacious, with high quality finishes and tall windows.

The buildings are timber-framed, using panels manufactured off-site by passive house veterans Cygnum. Walls incorporate Warmcel recycled cellulose <a href="https://passivehouseplus.co.uk/internal-insulation&quot; data-tipcontent="

Insulation applied to the inside of a building, sometimes called dry lining

” data-tiptheme=”tipthemeflatdarklight” data-tipdelayclose=”500″ data-tipmouseleave=”false” data-tipeventout=”mouseout” title=”insulation”>insulation within the panels and rigid insulation boards on the outsides. The front elevations of the houses, and the blocks of flats, are clad with light-coloured clay bricks; the rear elevations of the houses are simply rendered (a value engineering casualty), and the render is coloured to match the brickwork.

To achieve passive house insulation standards, the brick-clad walls are approximately 600 mm thick, including the cladding, and the rendered walls are approximately 500 mm thick, so windows have deep, insulated reveals, sills and soffits. Window openings, which are larger than the windows themselves, expose the rendered insulation layer externally as window surrounds, and have pre-cast concrete sills.

The windows themselves are triple glazed Idealcombi Futura+ composite units with powder-coated external sills.

The roofs are mostly shallow pitched (~30 degrees), facing north or south, with some steep pitched (~80 degrees) roofs on the larger houses and blocks of flats. All roofs are covered with shiny black glazed pantiles, with minimal eaves overhangs and clipped verges. The average tested <a href="https://passivehouseplus.co.uk/airtightness&quot; data-tipcontent="

The degree of air leakage or air infiltration a building has. Making a building airtight essentially means eliminating draughts. Ideally we want to have total control over how much air we’re letting in to the building through designed ventilation systems, rather than cold air entering (and warm air escaping) uncontrolled through unwanted or unseen gaps.

Airtightness is typically measured in two units: air changes per hour (ACH) and air permeability (m3/hr/m2). For a typical building, there is usually little difference in the two figures. The smaller the airtightness figure the better. Under Irish building regulations new homes must have an air-tightness of 10 m3/hr/m2. The rigorous Passivhaus standard demands an airtightness of 0.6ACH or less.

” data-tiptheme=”tipthemeflatdarklight” data-tipdelayclose=”500″ data-tipmouseleave=”false” data-tipeventout=”mouseout” title=”Airtightness”>airtightness of the <a href="https://passivehouseplus.co.uk/building-envelope&quot; data-tipcontent="

The exterior shell of the building, including the external walls, windows, floor and roof.

” data-tiptheme=”tipthemeflatdarklight” data-tipdelayclose=”500″ data-tipmouseleave=”false” data-tipeventout=”mouseout” title=”Building envelope”>building envelope for the development is 0.57 air changes per hour at 50 Pascals (see ‘In detail’ for more).

All homes have central heating systems consisting of gas-fired <a href="https://passivehouseplus.co.uk/condensing-boiler&quot; data-tipcontent="

A condensing boiler can re-capture some of the heat normally released in the form of hot gases, and use it to heat up water returning from your central heating system. This means that it requires less energy to produce a given amount of heat, and is therefore more efficient.

” data-tiptheme=”tipthemeflatdarklight” data-tipdelayclose=”500″ data-tipmouseleave=”false” data-tipeventout=”mouseout” title=”Condensing boiler”>condensing boilers supplying heat to radiators, and hot water. Ventilation is provided by Paul passive house certified <a href="https://passivehouseplus.co.uk/mvhr&quot; data-tipcontent="

See ‘mechanical heat recovery ventilation’

” data-tiptheme=”tipthemeflatdarklight” data-tipdelayclose=”500″ data-tipmouseleave=”false” data-tipeventout=”mouseout” title=”MVHR”>MVHR systems. Internal air quality is excellent, and residents report minimal use of the heating. For architectural reasons all flues and ventilation terminals are located on the rear elevations.

There is scope for solar <a href="https://passivehouseplus.co.uk/photovoltaic&quot; data-tipcontent="

A technology that uses energy from the sun to produce electricity

” data-tiptheme=”tipthemeflatdarklight” data-tipdelayclose=”500″ data-tipmouseleave=”false” data-tipeventout=”mouseout” title=”photovoltaic”>photovoltaic (PV) panels to be added to the south-facing pitches, in the future, to bring the energy performance of the homes close to ‘net zero carbon’.