388.1 - passive housing revisited | Scoins.net | DJS

388.1 - passive housing revisited

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I've written several times about the need to change our demand for energy. This piece starts from and award-winning article and turns steadily to what one might, as an individual, do about this.


This article won an award for clarity of explanation. It is about climate change and what it would take to reach net zero. The point, I think, is that we have bought into the idea that we need to remove CO₂ from the atmosphere by plants or technology or both. Fine, but at the very same time that seems to have resulted in the attitude that we burn now and pay later. I don't quite agree, but I do recognise that this adequately describes the observed behaviour; "Quick, let's use up the gas [or petrol, burn fuel in general, timber even] while we're still allowed to do so" is how I'd characterise the reaction.

The issue seems (I cannot be definite, which is frustrating) to be that we have somehow settled on the idea that change must be incremental, and that by this we do not mean steadily more change, but doing as little as we can get away with. What I think we need is more nearly the opposite, that we accept we need to make huge changes because it will take us so very long to enact such change (a generation, I expect). Acceptance of change would permit change to occur; what we have sold ourselves is the idea that change must occur but not yet. Each year we allow to pass with no reversal changes the planet we inhabit and is making the things we could do become more difficult. For example, we might plant a lot of trees but we're losing them to wildfire and forest clearance at a rate I suspect cancels out what we have actually managed to plant.

An example of kiddology that the article points to bases its argument upon the use of modelling. I have every reason to support such an approach, but, as my wife often has said, if is a surprisingly short word that is so easily missed. So, for example, we postulate the concept of carbon capture (and storage), we explain how it would work and we build it into the models. Consequently it is built into the economic planning. But, along the way, the conditional state—that assumption that we've actually built it and made it work—has been lost. We're in cloud-cuckoo land here, telling ourselves it's all fine when it really isn't and we're still careering to the cliff edge. We haven't made carbon capture work, and I explored some of this when we were short of CO₂ (patently ridiculous, since a surfeit is seen as the root problem).

So what it is that we're not doing is recognising that we need to spend—in volume, at a rate we've not seen since world war—so as to have any chance at all of arresting the situation, let alone reversing it. I do not see us doing so, nor do I see this occurring anywhere except on the private estates of the significantly rich. Sources [32-34] suggest that the extra cost of new build varies widely but in the UK might be up to 30% more than 'traditional' techniques. German figures suggest 3-8% additional cost, so we might view the British figures as falling between 0 and 30% with a mean nearer 10% (as the additional cost). As building regulations change (raise standards), so this additional cost falls, as the difference in standards reduces. The reasonable information centres on new build, when, given the state of UK housing, it is the cost of conversion that we really need to know.

The problem at an individual level might be described as "What do I do to significantly raise the insulation of my house?" with the obvious consequence of dramatically reducing the energy requirements of that building. Accepting that target, I find myself returning repeatedly to the disparity between the prospect of significantly changing my current house for some other house that I could convert. Changing house fixes my own issue but simply leaves the 'old' house as unresolved and for others to eventually fix. Yes, I'd have several avenues open to me if I didn't live in a conservation area and I see this as a significant impediment, not only for myself but in the wider context. Within a conservation area, any plan therefore starts from an assumption that the external skin must remain as it is, but that one might strip the interior completely. I suspect that one should plan to live elsewhere while the building work occurs, with additional costs (mitigated a little by improved performance from the builder because you're not in the way all the time). It also seems to me that, if stripping the interior, you might as well rethink the whole plan, not just moan about the lost finishes. Which means that 'moving out' is the full performance, amounting to actually leaving; nothing left onsite. In effect, you need to move house so you can not move house. Thinking of the house I live in, I see this as costing about as much as the house is worth, certainly half of that value. This needs further exploration.

[30]  https://theconversation.com/climate-scientists-concept-of-net-zero-is-a-dangerous-trap-157368?utm_medium=email&utm_campaign=Latest%20from%20The%20Conversation%20for%20June%2016%202022%20-%202322523139&utm_content=Latest%20from%20The%20Conversation%20for%20June%2016%202022%20-%202322523139+CID_53c6eee2cbb2689da70367c2a8825179&utm_source=campaign_monitor_uk&utm_term=an%20article%20we%20published

[31] Essay 262 which points to several other essays AND, I discovered today, I wrote that a pandemic might be a good way of reducing population. Dated 2018, so prior to covid. Ouch.

[32]   https://ecoarc.co.uk/first-retrofit-passive-house/   

[33]   https://buildpass.co.uk/blog/what-is-passivhaus-retrofit/   A suggestion here that 30% of current house value is a sensible budget to change to a passive energy state. Google Passivhaus. A different read of the same information says that the build costs are 100-130% of previous, traditional methods.

[34]   https://www.passivhaustrust.org.uk/UserFiles/File/Technical%20Papers/150128%20PH%20Capital%20Costs.pdf  Discussion of passivhaus capital costs, 2015.

I think it quite likely that this page will move to a subpage, say §388.1



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