EnerPHit changes to 20kWhr/m2yr in Southern England

Whilst this helps with achieving low energy retrofits and buildings, coupled with another change this has serious implications for future refurbishment projects.  The PHI has reclassified the targets for EnerPHit dependent on the climate  the project is in, reducing from 25kWh/m2a to 20kWh/m2a in Warm Temperate zones.

The zones affected include London, Efford and Exeter, or zones 1  3 and 5 within the PHPP model.

Following the releases of the new PHPP 9, we’ve completed a number of PHPP models for early stage projects looking to retrofit to EnerPHit or even Passivhaus standards.  One interesting discovery that has implications is the fact that some areas in the UK are now classified as Warm Temperate rather than Cool Temperate.

Interestingly, the climate also shifts the other way in the North, with some areas of Northern England and Scotland changing from Cool Temperate to Cold, dependent on the altitude of the project site.  Again a small change, but the EnerPHit target changes to 30kWh/m2a, which could come in handy if you’re retrofitting in Wanlockhead, Scotland’s highest village at 402m above sea level.

The altitude is significant in each case, due to the PHPP accounting for higher sites by reducing the temperature by a constant 0.6K per 100m difference to the climate station.  Zones where the data is collected with a low station may be overly affected by this assumption, or this may be an accurate representation of the changing of altitude (I’m not a Climate Scientist…).  Further information is on the Passipedia website here.

This means that all EnerPHits in London will need to meet the 20kWh/m2a target, as will many further south in zones 3-6.  It also raises the question about EnerPHits following the component route, and in particular with windows, as the requirements for U Values reduces in Warm Temperate climates from an overall 0.85W/m2K to 1.05W/m2K.

This may result in a higher take-up of the component route in southern England. Further information on EnerPHit component route and its criteria can be found here.

Below we have summarised the climate zones in a table, showing which areas may be affected.

Patrick Osborne 18/01/2016

Climate Zone of stationWarm Temperate20Cool Temperate25Cold30Counties in Climate ZoneApproximate Highest point in area
Zone 1 – LondonWarm Temperate0-145m146m-711m712m+Inner London134m
Zone 2 – Thames ValleyCool Temperate0-517m518m+Surrey, Berkshire, Oxfordshire, Buckinghamshire, Bedfordshire, Hertfordshire297m
Zone 3 – London GatwickCool Temperate0m-578m579m+Kent, East Sussex, West Sussex280m
Zone 4 – EffordWarm Temperate0-127m128m-657m658m+Hampshire, Dorset286m
Zone 5 – ExeterWarm Temperate0-125m126m-656m657m+Devon, Cornwall621m
Zone 6 – LynehamCool Temperate0m-540m541m+Somerset, Wiltshire, Avon, Gloucestershire, Gwent, West, Mid, and South Glamorgan519m
Zone 7 – Sutton BonningtonCool Temperate0-423m424m+Hereford, Worcestershire, Warwickshire, Northamptonshire, Leicestershire, Nottinghamshire, Derbyshire, Staffordshire703m
Zone 8 – FairfieldCool Temperate0-526m527m+Clwyd, Cheshire, Merseyside, Greater Manchester, Lancashire628m
Zone 9 – CarlisleCool Temperate0-331m332m+Cumbria, Dumfries and Galloway978m
Zone 10 – EskalemuirCold0-188m189m+Scottish Borders, Northumberland, Tyne and Wear840m
Zone 11 – LeemingCool Temperate0-318m319m+North Yorkshire, Durham, Cleveland788m
Zone 12 – WaddingtonCool Temperate0-443m444m+Lincolnshire, Humberside, West and South Yorkshire, Nottinghamshire582m
Zone 13 – HemsbyCool Temperate0m-526m527m+Cambridgeshire, Norfolk, Suffolk, Essex147m
Zone 14 – SennybridgeCool Temperate0-457m458m+Dyfed; Powys, Gwynedd1085m
Zone 15 – Glasgow AirportCool Temperate0-264m265m+South Ayrshire, East and North Ayrshire, South Lanarkshire, Inverclyde, East Renfrewshire and Renfrewshire, Glasgow, North Lanarkshire, Stirling, Argyll and Bute1174m
Zone 16 – DundeeCool Temperate0-238m239m+Tayside, Clackmannanshire, Fife, Angus, Dundee, West Lothian1068m
Zone 17 – AberdeenCool Temperate0-178m179m+Moray, Aberdeenshire, Aberdeen1309m
Zone 18 – AviemoreCold0-176177m+Skye and Lochalsh, Lochaber, Caithness, Sutherland, Ross and Cromarty, Badenoch and Strathspey, Nairn, Inverness1344m
Zone 19 – StornowayCool Temperate0-163m164m+Western Isles799m
Zone 20 – Kirkwall AirportCool Temperate0-59m60m+Orkney481m
Zone 21 – LerwickCold0-7m8m+Shetland450m
Zone 22 – Belfast-AldergroveCool Temperate0-362m363m+Fermanagh, Tyrone, Londonderry, Antrim, Armagh, Down,850m

Values taken from PHPP v9.3.  Where altitudes of the climate zone are not met, i.e. the highest point in the area is lower than that of the switch to a different climate zone, the figures are greyed out.  Please note this includes a minor correction to PHPP v9.3 please speak to your certifier for details, and if you get different results than above.

Updated 03/02/2016 

By |2017-07-07T13:11:39+00:00February 4th, 2016|Concepts, Passivhaus, Residential|

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