Tue, 09 Jun 2026 08:24:20 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=7657&Focus=114184#Comment_114184 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=7657&Focus=114184#Comment_114184 Thu, 04 Aug 2011 12:32:21 +0100 PeteLawley
Its tricky because every standard/ measuring device uses different criteria. However, I am fairly confident that the primary energy (all energy use + transmission losses) and space heating calculations from SAP and those used by Passivehaus are comparable.

So, imagine my surprise. I modelled a house to passivehaus standards in SAP 2009 and got a spaceheating requirement of 36.59 kWh/m2/yr but a primary energy usage of only 25.5 (passivehaus minimum standards are 15 / 120 kWh/m2/yr respectively)

Any ideas anyone?

Also, can anyone know what the average space heating requirement of a dwelling to ADL 2010 is (in kWh.m2/yr)

Thanks]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=7657&Focus=114193#Comment_114193 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=7657&Focus=114193#Comment_114193 Thu, 04 Aug 2011 13:31:57 +0100 djh Posted By: PeteLawleyHowever, I am fairly confident that the primary energy (all energy use + transmission losses) and space heating calculations from SAP and those used by Passivehaus are comparable.
I don't think your confidence is shared by many other people. The first link I found was http://www.greenbuildingstore.co.uk/page--passivhaus-and-csh.html but there are plenty more.

What did your PHPP model of the house show, BTW? And if you haven't done one, how do you know it is 'to passivehaus[sic] standards'?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=7657&Focus=114202#Comment_114202 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=7657&Focus=114202#Comment_114202 Thu, 04 Aug 2011 14:24:50 +0100 PeteLawley
It doesn't give either primary energy usage of space heating by both SAP and PHPP though. I guess to know how similar the calculations are we need to find both. This paper goes into more detail http://www.ukgbc.org/site/document/download/?document_id=494, and you are correct - they are very different.

The PH comparison is a bit of sideline really, I was trying to find a way to accurately compare annual energy costs of our timber panel system with a house built to current building regulations (without fiddling with SAP until I just about reached the minimum standards), but because ADL 2010 uses DER/TER rather than FEE I have been unable to find anything useful on the web.

Then, whilst reading about Passivhaus standards I thought it would be interesting to see how our buildings would perform if I upped the spec to minimum PH standards, thats when I discovered the discrepancies that I mention.

Always happy to be told there are beter ways to do things.....?

P]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=7657&Focus=114203#Comment_114203 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=7657&Focus=114203#Comment_114203 Thu, 04 Aug 2011 14:46:52 +0100 PeteLawley
It makes me wonder what our SAP space heating requirement of around 60 kWh/m2/year would look like through PHPP...?

P]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=7657&Focus=114259#Comment_114259 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=7657&Focus=114259#Comment_114259 Fri, 05 Aug 2011 13:46:19 +0100 djh
PHPP is only £120 or so and fairly easy to learn to drive in a basic fashion. I'd suggest taking a course if you want to understand it properly though (still on my to-do list).]]>