ISTR that this thread was (once) about the residential building regs, but indeed this applies even more so to commercial buildings. There are plenty of well publicised timber framed sports halls, concert halls, offices, schools etc, and even tower blocks, bridges, carparks that demonstrate how it could be done.

Timber is renewable on the time scale of a building -in fact the carbon can stay locked up for longer in a timber frame than in does in a tree. Most of the timber in my house has been here 150 years so far, and likely will last the same again. It's nothing at all like "paper mills and heating plants" where the timber is burned faster than the replacement tree can grow.

Timber beams are reusable as-is, if their first building is demolished, or can be recycled into timber derivative products, or burned for heat. They are easier to repair or modify than steel.

So sorry I don't agree that's using "no-renewable and non-recyclable materials with potentially shorter lifespans." Steel is non-renewable, and "recycling" it at 1500⁰C consumes large amounts of energy.

Posted By: SimonDwe transitioned away from timber suspended floors in the UK as a result of using up our native supplies during WWII and needing a local material for replacement which was concrete

I'm curious about this. I don't remember ever reading about any such policies etc before and I know my parent's house had timber floors downstairs as well as upstairs when it was built in the 60s. Our own previous house was built in the 70s and that had a concrete slab plus timber upstairs. Our current house has a passive slab and metal web timber joists upstairs. It feels like those decisions were all taken for reasons of economy and convenience, rather than materials policy. Is there any digestible background reading around your statement?

<blockquote><cite>Posted By: SimonD</cite><blockquote><cite>Posted By: WillInAberdeen</cite>

it is not as a renewable as once thought, as consequence of the forestry practises and all the ancillary practises required to process and distribute. </blockquote>

That's interesting. I suppose that could potentially also apply to any "renewable" product.
In a strict sense one could almost argue that human life itself is not sustainable, unless all the requirements are obtained within walking distance of the home.

Perhaps being a subsistence farmer is sustainable, but a management consultant or IT engineer is not?

Neither does the tree have zero impact, at least when used to make joists in houses, That I took to be the point the report was making. So we ought to be looking wider than just the direct impact of the tree itself, in growing and regrowing after felling, but at the associated costs of processing and using the joists, and then comparing those with the costs of using concrete instead.
It's becoming recognised that sustainable food production is not so sustainable if it needs transporting halfway round the world to get here. My point was simply that other processes regarded as sustainable might not be if examined the same light. Or even that an unsustainable process just down the road might not be so bad if viewed in the round.

In short, what exactly does sustainable mean?

Posted By: Cliff Pope

Posted By: SimonD

Posted By: WillInAberdeen

it is not as a renewable as once thought, as consequence of the forestry practises and all the ancillary practises required to process and distribute.

That's interesting. I suppose that could potentially also apply to any "renewable" product.
In a strict sense one could almost argue that human life itself is not sustainable, unless all the requirements are obtained within walking distance of the home.

Perhaps being a subsistence farmer is sustainable, but a management consultant or IT engineer is not?

Yes, at one end of the spectrum I think one could almost argue that human life is not sustainable, at least not as it is structured today.

I'm a bit of a self-confessed nerd when it comes to these things, but I have come to think that our current, modern approach to nature was predominently formed around the 1600s. Since then we've come to approach nature in the broadest sense as seperate from the human race. As a consequence we've see nature as being there to satisfy our needs, wants, and desires, without consideration that the resources being consumed in doing so are finite. There's also a clear sociocultural preponderance towards nature where it appears to be our objective to subjugate, control, and battle with it to retain control.

As EF Schumacher pointed out in his book Small is Beautiful, we don't treat natural resources as capital and don't measure the burn rate of that capital. If we did, we wouldn't behave they way were are and business and industry would be run much more considerately and frugally in relation natural capital.

Posted By: Cliff PopeSo we ought to be looking wider than just the direct impact of the tree itself, in growing and regrowing after felling, but at the associated costs of processing and using the joists, and then comparing those with the costs of using concrete instead.

I agree. I'd like to see much more Life-cycle assessments being conducted to assess sustainability of activities and products, even if LCA is slightly limited in terms of the measures used for assessment. But we've got to start somewhere. We also need to revisit studies on a regular basis as, for example, energy production decarbonises.

I've done some feasibility studies where instead of using narrow assessment measures I've insisted upon looking at the whole life-cycle, which definitely can change the picture significantly. In one project it yielded the proposed development to be unviable. For example, looking at heatpumps, an LCA would show that pumps can use as much as 120kg of steel, something like 30kg of copper, plus numerous other materials. When taking into consideration the impact of additional mining and processing, nobody seems to have done the calcs to really know the wider impact of these heating systems on the scale being proposed. That's not even considering additional emitter volumes.

More amusingly, a professor I know calculated the carbon footprint difference between an organic 'sustainably' farmed apple sold in a supermarket that came from Italy and non-organic one down the road in Devon. As you've pointed out the local one won hands down, but in some cases it doesn't if like many fruit and veg it's sent half way across the globe to be washed and packaged - a process that has been heavily used by scottish raspberry producers for example.

Our production and distribution systems are unfortunately so opaque it's almost impossible to measure them fully; they're so integrated it's also almost impossible to unplug from the system.

WillInAberdeen quoted:

"Importing vegetables grown in [warm countries] has a lower impact than UK vegetables which are cultivated in heated greenhouses, despite the transportation."

"asparagus has the highest per-kg impacts across most of the 19 impact categories considered, while cabbage, celery and Brussels sprouts are generally environmentally most sustainable [because they grow here unheated]"

Hmm, I'm not sure I agree with either of those statements. For the first, surely it depends on how the plants are grown? I'm thinking particularly of tomatoes and the greenhouses described in

https://www.edp24.co.uk/news/business/norfolk-and-suffolk-tomato-greenhouses-nearing-completion-1593518

For the second, we sometimes buy asparagus straight from the field it is grown in up the road. i.e. "they grow here unheated". So again I can't accept the statement at face value.

Building Regs are a complete mess, because of the process behind them. We need to sort that out a lot more urgently and importantly than we need more regulations. We still have fire regs that aren't fit for purpose.