Of interest

PHPP WARM Results Sheet v6.01 Released – PHPP9 Compatible!

Posted by on Dec 2, 2015 in news, Of interest | Comments Off on PHPP WARM Results Sheet v6.01 Released – PHPP9 Compatible!

PHPP WARM Results Sheet v6.01 Released – PHPP9 Compatible!

Dear all, We are very proud to announce the latest release of our popular results sheet. This release represents a big overhaul, and includes lots of new features, as well as improvements to usability. It is compatible with PHPP8 and PHPP9. Download link:   PHPP WARM Results Sheet v6.07 (204.2 KiB, 5,232 hits) [Edit 02/12/15: updated to v6.02] The biggest improvement is the addition of 3 new sheets that show a summary of the key data in the PHPP. Hope you find it really useful. Liam McDonagh-Greaves,...

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New PHPP Guide: Formulae to Make Solid Shading Transparent

Posted by on Nov 9, 2015 in Guides, news, Of interest | Comments Off on New PHPP Guide: Formulae to Make Solid Shading Transparent

New PHPP Guide: Formulae to Make Solid Shading Transparent

Dear all, We have published a guide to applying a transparency factor to objects in the shading sheet in your PHPP. Let’s say you are modelling a line of trees in your PHPP. The spreadsheet assumes that they are completely opaque, but this isn’t true – some degree of light always gets through. This guide shows you how to apply some transparency to those trees, making your shading more accurate. It is also useful for modelling non-solid fences, brise-soleils and pergolas. Download link:  PHPP Formulae to Make Shading Transparent (DEPRECATED) (220.1 KiB, 2,680 hits) Hope you find it useful! Liam McDonagh-Greaves,...

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New PHPP graphical results sheet to download from WARM

Posted by on Jun 24, 2011 in Of interest | Comments Off on New PHPP graphical results sheet to download from WARM

I’ve just uploaded an add-in graphical results sheet for PHPP. We’ve refined it to what we think are the key outputs – so we hope it’s helpful in your designs : ) To use – load both your PHPP and the results sheet – then copy the tab from the results sheet to your PHPP – all the links should start working. John   Download it:  PHPP WARM Results Sheet v6.07 (204.2 KiB, 5,232...

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Passivhaus vs the UK approach – a non technical comparison of the different principles

Posted by on Feb 11, 2011 in Of interest | Comments Off on Passivhaus vs the UK approach – a non technical comparison of the different principles

I’ve been working with Passivhaus for a year now, having previously worked with the UK approach of SAP and Building Regulations.  The technical differences are interesting, but the subtle differences in principles are where we have the most potential to learn. It’s important to recognise their common ground, and by ‘they’ we are really talking about two different ways influencing the design of a building in order to reduce its energy use.  We are not really talking about which is easier or harder, the Passivhaus standard is clearly more demanding, we are talking about different principles. They both use a model to predict energy use, Passivhaus uses the Passivhaus Planning Package (PHPP), and the current UK approach uses SAP 2009. They also both have a set of targets against which compliance is judged – the Passivhaus standard and the Building Regulations Part L. Rewarding good shape For the UK approach, Part L relies on what is called a ‘notional building’ comparison. This sounds confusing, but is really very simple.  It says that your building must be better thermally than if you built it using the energy efficiency standards of 2002 Part L.  This effects basic design,  because if you’re only comparing your building with itself, nowhere are you comparing it to a building design that has fundamentally more efficient shape.  Passivhaus on the other hand compares your building’s energy use to a fixed target – the well known 15kWh per m2 of useful floor area, per year.  This pushes the design towards a more efficient allocation of heat loss area to useful floor area, better orientation and better consideration of the quantity of glazing. This makes PHPP an invaluable tool at the initial design stage for optimising the design fundamentals, and the UK approach much less useful. The UK approach certainly has its advantages, for example the ‘notional building’ model is a lot more forgiving of certain errors.  If the SAP assessor enters extra wall area, it doesn’t really matter in compliance terms because the notional house will have exactly the same amount of extra wall area – and thus both result and target move in parallel.  Passivhaus in contrast has a fixed target and relies critically on the competence of the assessor. The UK approach comes down to simply judging compliance, whereas Passivhaus and PHPP guide the whole design towards an efficient, low energy solution. Considering Comfort Another key difference in principles is found in the drivers behind Passivhaus and the UK approach.   The Passivhaus driver is human comfort: cold draughts are eliminated and the cold radiant effect is minimised with a purpose.  This purpose is to create an environment where a person can be warm and comfortable without compensating for a poor atmosphere by turning up the thermostat.   The UK approach has nods toward comfort: a maximum air leakage rate, backstop U values and consideration of summer time overheating.  However, if you want to roll back the air leakage and U values to backstops and compensate with solar PV you will still comply with building regulations, but comfort certainly won’t be the priority. Closing the design loop An interesting difference has become apparent to us recently with the changes in the treatment of thermal bridges in the UK approach.  Consideration of thermal bridges is absolutely essential in designing a low energy building so broadly I welcome the more robust treatment in the 2010 regulations. However, again the difference in principles with Passivhaus is interesting.   PHPP, the Passivhaus model, is based on external measurements of the building.  These, being inherently larger, build in a margin into the standard...

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Whats do Google trends tell us about sustainable building in the UK?

Posted by on Sep 7, 2010 in Of interest | Comments Off on Whats do Google trends tell us about sustainable building in the UK?

I found Google insights today and wondered what it tells us about the current trends in UK sustainable building, if anything? Firstly, out of the voluntary standards in sustainable construction: Code for Sustainable Homes and Passivhaus – which is getting more interest? I’ve also added Zero Carbon Homes into the mix. These are the results: It’s quite clear that Code has still got the edge in Google search terms, but equally Passivhaus is gaining interest quickly. Although you could argue they are not really comparable as Code covers a range of sustainability issues, whilst Passivhaus is a much more rigorous comfort and energy standard. The above chart is live, so it will be interesting to see how it changes over time. Also interesting is how much interest feed in tariff is generating (please excuse the pun): And how various renewable energy options compare to insulation: The above graph shows insulation is still generating much more interest than any of the obvious renewable options, which is good news for those of us who believe in improving a building’s fabric before bolting on renewables. However, solar panels do look they are gaining in interest quickly – perhaps due to the feed in tariff. Interestingly you can see that interest in insulation is seasonal, with clear winter peaks. Google also tells us that most people are searching for wall insulation, loft insulation and cavity insulation. The biggest growth in insulation search terms relates to grants. If anyone can think of any others I could add – please drop me an email at...

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