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Power

Entire Buildings Can Be Wrapped In Jackets To Save Energy (scientificamerican.com) 80

An anonymous reader quotes a report from Scientific American: On a normally peaceful residential road outside The Hague, the Dutch city that serves as seat of government, the whine of a hoisting crane and welding tools heralds a not-so-quiet housing revolution. Four workers standing above me on a scissor lift next to an apartment complex guide a thermally insulated facade 40 feet wide and one story tall into place against the existing wall. Its brickwork pattern of muted brown, grey and beige, and the triple glazed windows, perfectly fit the building's existing frame and openings. The original windows and the very old brick walls had allowed cold drafts inside, and warm interior air to escape, wasting much of the energy used to heat the building. The new facade is primarily fire-resistant expanded polystyrene -- essentially, hollow spheres that trap air to create a thick insulation layer -- faced with hardened clay and sculpted into hundreds of very thin rectangles known as "brick slips."

This new building skin, prebuilt in a factory, was one of a dozen such facades to be attached to local buildings when I visited the suburb on a rainy day in early summer, each structure measured to millimeter precision. The installation is part of a concerted effort to transform energy-inefficient public housing into a set of ultralow-emission homes -- without having to open a wall or remake an attic. The building was being wrapped in the equivalent of a winter jacket -- or summer beer koozie -- avoiding the need to insert insulation inside dozens of walls, lofts and attics. A similarly premade, lightweight, highly insulating material, complete with solar panels, would be installed on the roof, too.
The report notes that the average cost to retrofit a family home in the Netherlands is "about $94,000," but it's "comparable to the cost of other routine renovations that deliver no energy savings."

"In one neighborhood in the city of Utrecht, more than a dozen houses and some 250 separate apartments retrofitted in 2019 saw their energy requirements fall from 225 kilowatt-hours per square meter to just 50 kilowatt-hours per square meter, on average. The remaining demand for energy was met with solar power."
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Entire Buildings Can Be Wrapped In Jackets To Save Energy

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  • by Ostracus ( 1354233 ) on Thursday July 29, 2021 @11:58PM (#61636901) Journal

    The report notes that the average cost to retrofit a family home in the Netherlands is "about $94,000," but it's "comparable to the cost of other routine renovations that deliver no energy savings."

    Clearly "other" isn't insulation inside dozens of walls, lofts and attics.

    • by steveha ( 103154 ) on Friday July 30, 2021 @02:44AM (#61637045) Homepage

      I currently live in a home that was built in 1979. We had an insulation upgrade. We got new triple-pane windows and more insulation in the attic crawl space... and that was about it.

      The company said there wasn't much they could do with the walls; the walls didn't have enough interior volume to really upgrade the insulation.

      Also this home was not built to be airtight. It's downright drafty in places. The modern trend is to build things really insulated and really airtight so that there is not much energy loss.

      I'm not a building expert but I think adding a new "jacket" layer would be the only way to significantly improve the exterior insulation of this home.

      • by HiThere ( 15173 )

        Making buildings airtight has significant downsides. It tends to encourage various pollutants to accumulate in the interior spaces. Like the plasticizers emitted by a new carpet.

        I agree that it would be better to just prevent those emissions from ever happening, but there are multiple sources, and they aren't all obvious. Is the basement also air-tight? If not you may be accumulating Radon. Etc. Not to mention that if people live in the house people emit various gases, not all detectable. CO2 is just

        • by Z00L00K ( 682162 )

          I'm more concerned by the risk of mold due to enclosed humidity.

          However a good ventilation system with heat exchangers can do wonders.

          • You shouldn’t be. Air Barriers are vapor permeable.
            • by Z00L00K ( 682162 )

              And that's how you'd get mold in your walls in cold climate when the indoors humid air gets into the wall and condensates.

              • That’s why the air barrier is vapor permeable allowing the wall assembly to dry out. Trying to block water movement is the number 1 cause of mold. In the wrong climate vapor barriers trap water cause mold.
      • Surely insulating cladding would help? It's not exactly uncommon where I live, I saw numerous large buildings as they were upgrading them with insulating panels on the outside. They were doing these things a *decade* ago.
      • There is a limit to upgrading your insulation, having like this articles extended exterior walls, or extend the wall in your interior may be your only bet. Alternatively upgrading your HVAC to newer energy efficient systems may help too.

        When I got my home, it only had Oil heat, I have added a pellet stove, where even in cold winter days unless it goes below 0F I don't need to turn on the oil heat, and I recently added a heat pump system mostly for AC during the summer, but in the winter it helps event ou

    • Re: (Score:2, Insightful)

      by AmiMoJo ( 196126 )

      Retrofit is always more expensive that fitting it during construction.

      It's utter madness that new homes are still being built with gas boilers, for example. The cost to fit a heat pump is about the same if done at time of construction, or vastly more than a replacement gas boiler if done when the old one reaches EOL.

      • People have a problem with compromise and change.
        Heat pumps systems offer a lot of high value benefits, high heat per energy, low expenditure, less pollutants and most units are much quieter. But they don't work so well when the temperature gets really cold even though for most areas where people live, when the temperature gets that cold only is about 14 days a year, where the cost of using resistive heating is actually cheaper.

        When people are use to a technology, they don't want to to change, and if asked

        • But they don't work so well when the temperature gets really cold

          What temperatures are you talking about ? I just had a heat pump installed, that's rated to work down to -30C (-22F).

      • by sfcat ( 872532 )

        It's utter madness that new homes are still being built with gas boilers

        There are two reasons for this. One, developers mostly build new houses, not the people that will live in them. And developers don't care about such things, heat pumps are expensive and cutting out that cost is more important to them. Two, heat pumps don't work everywhere. Even worse, the belts where the most people live (because of temperate climate) are also where heat pumps are ineffective. Heat pumps work better where there is a higher temperature differential and thus more extreme environments (li

  • by digitect ( 217483 ) <digitect&dancingpaper,com> on Friday July 30, 2021 @12:03AM (#61636907)

    (Full disclaimer: I'm an architect.)

    Wrapping a building in an exterior "jacket" is only a small part of the larger building envelope. We've been hearing about insulation forever, but real professionals have been dealing with the larger building science issues of condensation, humidity entrapment and control, thermal bridging of intermediate conductive fasteners (brick anchors, nails, screws, etc.), even the embarrassingly large amount of bulk water that invades most buildings past parapets, flashings, windows, even brick cladding itself.

    The Grenfell Tower fire was, in part, brought about by cladding added to an existing building. Not only was the new insulation highly flammable, but so, too, was the exterior cladding panel itself. Plus, they didn't fire block very well, so the whole installation acted as a massive chimney drawing new oxygen to the fire as it burned.

    The fine article is missing any detail drawings whatsoever, but I'd say this idea is as new as a 1970's This Old House episode. Talk to an architect that understands building science and you might learn more about solutions that will help you in your specific climate. For example, here in North Carolina, our problem is humidity, not thermal control. Air leakage (and thereby, vapor) is arguably 10x more contributing to energy costs, indoor air quality (mold, pollen, insects, etc.), and comfort.

    • but real professionals have been dealing with the larger building science issues of condensation, humidity entrapment and control

      Locally, some rich guy hired contractors of the hippie-hating variety, and asked them to build a "green" mansion. So they wrapped everything in extra insulation.

      It was only two years before the walls were so full of mold that it was torn down.

      You need builders who care about their work, and that's hard to find these days; the construction trades are chock-full of anti-intellectuals.

      • The rich guys problem wasn't the contractors, but he didn't hire a qualified architect, also I expect he cheeped out in hiring a Project Manager as well.
        General construction work requires a lot of manual work, also the workers will often have to be great distance from their homes for the job.
        This means the prime demographic are young men, without families to be construction workers, This is also the same demographic range where people will go to college. So you are not going to get too many intellectuals

        • The rich guys problem wasn't the contractors, but he didn't hire a qualified architect

          God, your idiocy never ceases to amaze. Reality just shifts to accommodate your blathering, you think? Right? Whatever you imagine, that's what happened, right?

      • the construction trades are chock-full of anti-intellectuals.

        Brent Hull would take issue with that statement.

    • I think the Grenfell Tower was clad for aesthetic purposes and not insulation hence no care given to safety
      • I think the Grenfell Tower was clad for aesthetic purposes and not insulation hence no care given to safety

        The Grenfell Tower was clad in two things: insulating panels to improve the thermal efficiency, and on top of those decorative and protective panels to imporve appearance and protect the insulation.

        Whether primarily decorative or primarily insulating (everything on a building is insulating to some extent), it must still be safe.

        See https://en.wikipedia.org/wiki/... [wikipedia.org]

      • by ChumpusRex2003 ( 726306 ) on Friday July 30, 2021 @06:18AM (#61637363)
        The primary purpose was insulation. Under UK legislation and renovation or upgrade to a building must also enhance the energy efficiency of the building to meet modern standards. So, for example, if you build an extension to your 100 year old house - then not only must the extended part meet modern energy efficiency standards, the rest of the house must be upgraded too. So, insulation was a mandatory legal requirement.

        Aesthetics are also an important criterion for getting planning permission. Councils these days generally do not permit eyesores - hence it is necessary to convince planning inspectors that the aesthetics are suitable for the area.

        However, the insulation was relevant here. One of the targets of the council was to demonstrate "aspirational" energy efficiency. They specifically listed thermal specifications significantly in excess of the legal requirement as one of the core specifications that the contractors had to acheive.

        The architect when he got the thermal specifications wasn't sure that they were possible - so contacted all the insulation companies he had used before with and asked their technical support departments for details of fire-resistant insulation products capable of meeting these specifications. The replys came back that the specification was unachievable. The architect went back to the main contractor and the council to inform them that the thermal specification in the contract was unachievable and had to be changed. There then followed an increasingly beligerant exchange of e-mail between the customer and prime contractor, and the architect and insulation suppliers - with the prime contractor insisting that it was possible and the council was insisting that the spec was non-negotiable and would not be changed under any circumstances. After being unable to find suitable fire-resistant materials, the architect begged the prime contractor for advice to break the stalemate. The contractor suggested that he look at alternative materials, and suggested a type of PIR insulation which "they had used all over London, and never had a problem with building control".

        Eventually, an order went in for the PIR material. The supplier found out it was for a residential tower, and refused to supply it, stating that it was too unsafe. They substituted it for a fire-resistant version, which had a fire test certificate - however, the certificate was only valid for when the insulation was paired with a cement boards, and not used with any other type of combustible material, and certainly not the polyethylene outer cladding used.

        It later turned out that the test which the certificate applied to had been manipulated - The first test of the material at a laboratory failed spectacularly. Subsequently, the manufacturer of the material submitted it for a retest, but had secretly agreed with a technician at the test laboratory to insulate the thermocouples with ceramic.

        That said, the insulation waas only a part of the issue - the main issue was the flammability of the outer polyethylene panels. The architect and planning inspectors had initially wanted solid metal cladding - and had agreed on brushed zinc. However the council decided that they had to find cost savings and demanded that the architect/contractor cut the budget by 500k. The expensive solid zinc tiles would have to go. In fact things were worse, the prime contractor had mis-quoted when they signed the contract, and had under-estimated the cost of the project by approx UKP 1 million. The council would not reconsider the budget - the cost reduction was non-negotiable. The prime contractor was already in financial trouble and they could not afford to eat a UKP 1 million loss.

        At this point nothing mattered any more. For all the extensive effort and discussions about which shade of brushed zinc with brass accents, the only materials which were being considered were the absolute bottom-of-the-barrel materials which were would meet the budget requirements. Aluminium/Polyethylene composite was the cheapest material available - and nothing else would fit within the budget.
        • by hey! ( 33014 )

          Weird and unexpected things can happen when you scale up a system, so materials that resist burning in a bench test can burn intensely in a large installation. But this case the danger was already well known: the spacing between cladding and insulation creates a large vertical air plenum -- basically a chimney. The manufacturer recommended that the cladding used only be used in buildings less than 10m height.

          Somebody willfully ignored that and installed it on a 70m tall building; not only that, they did

    • I (with no knowledge except that of a DIY homeowner) was going to say something similar (albeit without half of your detail).

      I'm farther and further North than NC. Our building codes cover about six layers of materials in our walls -- including moisture barriers (e.g. big plastic sheet), and moisture releases (e.g. holes between bricks).

      Sure, I like insulation like anyone else. But those in warmer clients simply don't understand what ice can do.

      1. rain makes a wall a little wet
      2. snow sticks to the wall
      3.

  • How is this new? (Score:3, Interesting)

    by MacMann ( 7518492 ) on Friday July 30, 2021 @01:22AM (#61636983)

    I remember seeing an old brick building being renovated where a new facade was being constructed from large foam blocks, after being put in place the blocks were covered with a thin layer of some kind of mortar or cement to give it a durable weatherproof covering that made it look like blocks of limestone, granite, concrete, or whatever they like. After seeing it in the process of construction then I started to notice it everywhere. The fake stone can be differentiated from the real stone by looking for how it cracks. A large block will have long and deep cracks, but a mortar covered foam block will crack more like a window with many thin cracks. Another way to tell them apart is to give it a tap with your knuckles and listen. A rock will sound like a rock, a fake rock will sound hollow or like wood.

    The use of a foam block exterior is done on new construction too. On large expensive buildings that they intend to keep around for 300 years will not trowel on a mortar though. They will get the large stone block look with a steel frame holding up large stone panels. It might look like the stone is 3 feet thick but it's more like 3 inches, and the interior of the hollow block will have wires and plumbing, and of course insulation.

    This doesn't sound new to me. I suspect this kind of construction is 50 years old, with people looking for ways to lower heating and construction costs after heating oil started to get expensive in the 1970s. They also likely wanted to retain the look of big stone blocks so new construction didn't stick out too much in old cities.

  • The downside (Score:5, Insightful)

    by Wizardess ( 888790 ) on Friday July 30, 2021 @02:55AM (#61637061)

    Over the ridiculous number of years I have been alive I've noticed that buildings have a lamentable tendency to catch fire for the darndest silly or serious reasons. Polystyrene burns nicely. And both it's fire, it's flowing liquid preburning state, and its burned state's fumes are highly infelicitous to human life. I think I'd be inclined to skip on an opportunity to live in one of those buildings.
    {o.o}

    • by Viol8 ( 599362 )

      Good call. This is what happens when flammable materials are used on a building:

      https://en.wikipedia.org/wiki/... [wikipedia.org]

    • by Dusanyu ( 675778 )
      the other consern is somthing building contractors have been fighting for years "Sick Building Syndrome" https://www.epa.gov/sites/defa... [epa.gov] we can build buildings that are remarkably air tight and insolated and sould do the same with addons like described in the artical but you will allways have to have ventalation which will negitvly effect on energy use. heat exchangers are fantastic for solving this in new construction. retrofitting old construction is not as easy
    • Back in them olden days, a lot of buildings caught fire too. A combination of buildings made from mostly wood. Primary heating from Open Flames, people had an interesting pass time, of lighting various plants (Tobacco was a popular choice) on fire just to breath in its smoke, while often sitting down on cloth future, as well lighting often required some sort of open flame as well.

      Polystyrene while it does catch fire and burns like crazy, it is in general more difficult to get it in that state, these bui

  • Photos and Video (Score:5, Informative)

    by MDMurphy ( 208495 ) on Friday July 30, 2021 @02:58AM (#61637063)
  • Insulation to retain heat lowers the amount of fuel spent on heating an enclosed space. Up next, spear or bow, what is better for hunting down the wooly mammoth?

  • Cost vs. benefit (Score:5, Insightful)

    by bradley13 ( 1118935 ) on Friday July 30, 2021 @05:33AM (#61637289) Homepage

    Our previous house was built in 1934. We insulated the attic and replaced the windows. The next step would have been to insulate the outer walls, which were completely uninsulated (but about 50cm of solid brick). It was a large building, combined business private, about 500m2 plus another 250m2 of basement/garage. Using round figures:

    • Insulating the outer walls would have saved about 3000 liters of heating oil per year. That's roughly CHF 3000/year.
    • Cost for the insulation would have been about CHF 250,000
    • Math: that gives you a payback in about 80 years

    There's just no way this is worthwhile for private people. Perhaps doing whole apartment buildings yields some economy of scale, but it is notable that the government is paying for this. Likely, the payback is still not worthwhile in any economic sense. It is debatable, whether it is worthwhile in any sense at all - just how much energy went into producing those shells?

    Of course, tearing building down and replacing them is even worse. Really, the best solution for older buildings is to do the "easy" upgrades, including efficient heating systems, and otherwise live with them as they are.

    • Buildings can also be externally insulated. That ruins the aesthetics of your brick house but for houses which don't have any character it's a fine and cheaper strategy than insulating from within... as long as you don't use flammable siding. And ideally you don't use flammable insulation, but I speak from experience when I say the flammable stuff is by far the easiest to work with, and it also provides the best R-value.

    • but it is notable that the government is paying for this. Likely, the payback is still not worthwhile in any economic sense

      Your 240000 liters of heating oil over 80 years generate something like 700 tonnes of CO2, with a social cost of at least CHF 32000, but possibly several times than number if more comprehensive environmental effects are taken into consideration, and if the future marginal costs are applied (in an already warm climate of the future, any extra kg of CO2 may be doing considerably higher damage than today's estimate). So it may be still worth it for the government.

    • Nit Picking (damn nits): YOU are paying for this.
      The government takes YOUR money, keeps the majority for themselves, family, close personal friends, and for the people that have dirt on them.
      A small amount goes to 'Public Works' that they will take credit for, showing their magnanimity.
      Please make no mistake, they did NOT pay for it, YOU did under, threat of loosing all you own and possible imprisonment.
      This is often called democracy.

  • We hear that a lot (Score:4, Insightful)

    by nospam007 ( 722110 ) * on Friday July 30, 2021 @06:07AM (#61637345)

    "Why is polystyrene flammable?
    Polystyrene is a polymer made from styrene, a substance commercially manufactured from petroleum. This makes Polystyrene a thermoplastic substance, it melts when it is heated and spreads fire very quickly. It is classified as a 'highly flammable' or 'easily ignited' building product."

    The next big fire will tell us why it was a bad idea.

    • I agree that polystyrene can be flammable, but it's link to petroleum is irrelevant. Flammability of starting materials doesn't necessarily confer flammability to end products. Lots of materials are derived from petroleum because it's a source of saturated and unsaturated bonds, which make great building blocks for larger molecules. Not all of those materials are flammable.

      Also, polystyrene can have additives that change its flammability.

  • Some people dress up their dogs to keep them warm, why not put a fur fuzzy on their entire house?
  • by Fly Swatter ( 30498 ) on Friday July 30, 2021 @10:05AM (#61637857) Homepage
    Excuse me but they must not be using US dollars. $94,000 will buy you a new pool and a new garage. Or 4 new kitchens.

    Someone is deluded as to the cost of that 'energy blanket'. Or completely out of touch with reality. Perhaps they live in California.

    Currently $94,000 will pay for 52 years of heating oil, and I was being generous with the cost and my use per season. Also for me it would be much cheaper to just gut the home of drywall, add a row of studs to the outside walls packed with insulation, then hang new drywall. Granted I don't own one of these million dollar homes that has become common everywhere.
  • Maybe those buildings last century that used to install awnings over the windows in the summer were on to something? yes you can get a white vinyl tarp and string it up to shade your building during the day as well as make cheep white vinyl tarp awnings to shade you windows. A 2,100-sq-ft home requires a two-ton AC unit with a rated power consumption of 3,500 watts. Running the AC unit eight hours per day uses 868 kilowatt-hours per month of electricity. The cost of electricity from the grid per year at
  • We're supposed to live in closed boxes with no windows now? Screw that.
    • by PPH ( 736903 )

      Did you see the part about the triple-glazed windows in TFS? This sounds like they are upgrading the efficiency of older buildings by adding a 'wrap' to the exterior instead of tearing into them to add insulation. That wrap includes windows.

  • How long doe it take to save $50,000 in heating and will the hose cozy still be useable then, or do you need another one making it a zero sum game?
  • It basically says "oh neato! And then we can have solar!" with nearly no details, no data, no actual questions about flammability, moisture, long term consequences, etc.

    And not really even a picture of the shit being applied.

    Honestly, US News covers it more in-depth.
    Scientific American: Has hated America for a few decades now, and not even bothering with the science either.

  • Or, hear me out on this.

    Are you ready for this ground breaking idea?

    Add more insulation to houses when you build them, or higher grade insulation.

    It works. My friend's grandfather had a house designed with insulation for Arctic conditions, but in a temperate climate. It was cooler in the summer and warmer in the winter.

  • So Christo and Jeanne-Claude where right all along! They were wrappping buildings back in the 80's [wikipedia.org].

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