doesn't burn. What's not to like?
Er, that it doesn't burn?
Now that the Space Shuttle is being decommissioned, what are we to do with all that lovely high-performance insulation that protects it from the heat of re-entry? Silica aerogel is an amazing material: a solid foam consisting of over 95 per cent air, about the least material and the most 'hole' per unit volume and thus the …
Er, that it doesn't burn?
When I moved into my new house it has way better insulation than my mums place, I believe her house was built in the 1890s and hasn't been well modernised.
I now feel very hot in summer time as a result, when the sky is pure blue and the sun is blazing up to 30+ degrees C.
So how does an AeroGel insulated house fare in the hot summer?
If my improved insulation is anything to go by, then I'd imagine with the best insulator in the world it'll be somewhat unbearable, but at the same time if a derivative is used in the re-entry tiles for the shuttle, then it'll be keeping the heat out too, ambient temperatures then dominate, and that'll make it too hot?
Logically the thermal insulation should be a neutral factor, if you will be hot or cold will depend on sunlight or other heat or cold sources or draughts and ventilation. As far as I know that is why calculations need to be done on the properties of the glass being used in the windows (heat loss/retention/reflection), there are many different factors to consider to attain the best result. Probably best to get the advice of a pro in the field.
I would assume that if the aerogel keeps heat in, it can keep heat out too... of course, the leakage from the windows into the room may diminish your return, but it's still a thought... :-)
In summer the doors and windows will be open so the temperature inside will not build up beyond the ambient temperature at worst... How are you going to get it cooler with any sort of insulation bad or good? What usually happens is the external walls absorb a lot of solar energy and become a giant storage heater boosting the internal temperature and keeping it hot over night. With this insulation that effect would be dramatically lessened keeping the heat out and making the house a lot cooler in summer.
Or if you actually had any active cooling - air con etc - then the insulation will allow you to more easily maintain the temperature difference from inside to out. But that would not be very eco friendly.
@Stu: "If my improved insulation is anything to go by, then I'd imagine with the best insulator in the world it'll be somewhat unbearable"
Insulation slows heat from coming in through the walls just as well as it slows it from leaving. But it isn't the only design factor. The other factors in controlling the heat in summer are:
1) The size and (particularly) the orientation of glazing;
2) Shading/solar controls
3) Effective natural ventilation
In the northern hemisphere, for example, your openings should predominantly face south, where you maximise solar penetration in winter and minimise it in summer. Shading is also uniquely effective in this orientation (most effective in summer, least in winter). The design of the building (and ventilation mechanisms) can also ensure rapid natural ventilation of the entire house simply by opening key roof-lights or windows.
However, these concepts are better applied to new-build.
You need to remember basic physics theory. In fact, you need to remember the "perfect black body" experiment where perfect absorption of light and conversion into thermal energy is achieved by letting light through a small opening into a cavity and never letting it out.
So if you do not deal with the windows it will indeed become unbearably hot and will _NOT_ cool down at night. The same is valid for any modern house - it need blinds if you are not to die of heat stroke in the summer. Best kind are external rolldowns. Unfortunately while these are a standard feature on the continent they are nearly impossible to retrofit on a British house because the windows are put flush with the outer wall surface so there is no space for them (unless you put ugly side fascias as well). The same is valid for winter. Even with doubleglazing the windows will still leak heat so you will save more by having decent blinds than by wasting 100 quid per m2 on wall insulation.
In any case, insulating to the extent described in the article does not make any sense because do we like it or not we have to let fresh air into the house. I really would not want to be in a living room with 4 people which has been hermetically sealed so it "heats itself" from their heat. That is even if none of them have eaten any healthy fiber-rich diet. If you want to save a _LOT_ on your heating bill you actually need to build a good ventilation system with a heat exchanger. This however is once again very difficult to fit into a British house without ripping out all floors and re-plastering large portions of the ceilings. I am planning to do start putting some of that in on the next overhaul which unfortunately will be in 5-10 years or so (I made the mistake not to do that 10 years ago on the previous one).
@Anton Ivanov: "insulating to the extent described in the article does not make any sense because do we like it or not we have to let fresh air into the house..." [...]
"it need blinds if you are not to die of heat stroke in the summer. Best kind are external rolldowns"
Wrong on both counts - study up on environmental and passive solar design. Poor insulation does not equate to good ventilation, nor does good insulation mean poor ventilation. You are confusing two different design issues (and there are many others to consider). Strong insulation is always good (in the British climate at least).
And regarding shading, a simple, horizontal, louvered screen is very effective, provided the majority of the openings and shading is orientated roughly toward the south. It works all year around with no manual intervention.
How harmful is that dust when working with it? Where does the residue end up after installation? Any danger of more dust if you want to put up shelves?
and you will immediately find the datasheet that covers handling and best working practice- just as you would any other construction material. (select "Spacetherm", then RightHandClick >> "Search Google for...". Oh, a PDF is a file that requires a special program called Adobe Reader or alternative...)
Basically, wear protective equipment, disposable overalls, and be sure to vacuum up the dust regularly using a vacuum cleaner. Regarding the drilling of the installed sheeting for the purpose of erecting shelves etc, just hoover up the resulting dust or use one of many drill-dust reduction solutions available on the market.
'Penguin', cos they know something about insulation.
its a desiccant so similar to silica gel dust (wear a mask), its just lighter. a vacuum will remove it just like other dusts. Yes if you drill into it later the dust is still potentially a hazard, but again vacuum after as you would with plaster dust and all is well.
As anyone used to working with microfine silica will tell you, you should ALWAYS wear a dust mask or similar when handling it, or risk getting silicosis:
so could it be used as some kind of high end Ryvita or something?
It has a use.
Maybe if you laminated it with thin sheets of chipboard to add flavour and texture.
When eating chipboard, no need to contaminate with Ryvita.
"so could it be used as some kind of high end Ryvita or something?"
I think that bio degradable puffed packaging PC and network hardware comes in does the job nicely.
What those puffed cheese snacks would taste like if you washed off the cheesey tasting coating IE nothing.
Otherwise there is a serious risk of water vapour condensing on your nice cold timber frame and rotting it.
Adding insulation to the inside of a house is a much poorer way to do it that adding to the outide, as you have no thermal mass and the structure is cold and liable to freeze. Adidng an insulated render to the outside of the building would probably have been much more effective.
I once worked for builder in the holidays, he was building a neighbourhood swimming pool. To remove the risk of condensation forming on the inside walls (warm water, cold walls) they calculated that the dew point would fall Inside the wall. This was actually a good thing IFF you sealed the wall. I was largely employed in taping over the staples fixing plastic sheeting on the, wooden frame of the wall (over the insulation) to completely seal it (and help stop cold spots from the metal staples).
However trying that in a domestic situation is not really viable as people will want to pierce the plasterboard to hang stuff on the walls ruining the sealing.
Also the problem here in the UK is that not enough air flow is allowed in timber framed walls, that is the main reason you get rot from dewpoint damp. Houses in New Zealand (where this swimming pool was) have much higher air flow so the wall framing does not rot. Recent problems with rotting framing is due to inappropriate design and shoddy building resulting in ingress of rain water, not condensation.
"..Those holes are filled with air or a gas such as pentane."
Really? Pentane is flammable, a member of the methane, ethane, propane, butane....family of organic compounds. It has a boiling point of about 30 deg.C and so is used as a foaming agent.
The foam you describe was probably 'blown' (made into a foam) by mixing liquid pentane with it's base constituent and then heating it, so the pentane bubbled up and evaporated. I would think that the pentane was driven off by heating to be replaced by air diffusing in.
If the pentane has formed the voids of a closed cell foam, then it should burn quite nicely if you crush it and put a match to it. Can anyone comment on this subject?
The reference to pentane as a possible filler was in describing "off-the-shelf building insulation such as rigid foam and glass wool". In particular, n-Pentane is the primary blowing agent used in the production of polystyrene (which does, indeed, burn well).
I think this was what was being referred to in the article.
"With off-the-shelf building insulation.......holes are filled with air or a gas such as pentane."
The Aerogel is different it is not a foam it is a clear transparant solid that looks like glass but is stupidly lightweight a photo of some aerogel or these panels with the mesh inside would have helped this article no end.
Pentane should diffuse out readily even in closed cell foam
I have a room that is nearly totally external 3.5 of 4 walls ceiling and floor. (its above a staggered garage) I'm sure that it did not comply with the regs when it was built (2003).. anyway I have looked into the 40mm spaceblanket style insulation previously, but I only have 20mm behind the existing drylining and dont really want to reduce the room anymore! now I'm gonna have to look at this gel too! but where can I get it??!
The article itself names one supplier. Googling "Aerogel UK" gave me a few more on the first page.
Would also love to know. :-)
please keep us updated on any more home improvements! I'd never heard of aerogel, but will certainly look at trying to use it in the future
Blazing hot summers... I guess you don't live in the UK then.
Either way, a well insulated house tends to stay cool during the summer due to the insulation, thermal mass and average temperatures (over the night as well as the day).
For the author, my brief research into triple glazing indicated that it wasn't really worth it compared to modern double glazing. If you have old double glazing then replacing it will make a big difference either way, but the performance of modern triple over modern double is marginal.
These super-eco houses you see on Grand Designs are sometimes air-tight to prevent any energy getting out. Great so in winter you need no heating, but then don't you suffer from hotel-room syndrome (suffocatingly hot and no windows) in the summer?
So if it is hotter outside than inside, insulation will help keep things cool inside.
And you can open them! It's not that they're sealed boxes, instead the ventilation is precisely controlled so as to minimise heat loss. Ventilation is very important but is largely ignored, in the UK at least.
we just had the "spacetherm" stuff installed in our (council) house. It's good, but the contractors had a hard time installing the material. It's not easy to cut, it eats electric saws for breakfast dinner and tea. Insulation seems to be good, we run the heating less now, sometimes survive just on the heat stolen from our beloved terrace neighbours!
That stuff (the dessicated silica) looks a bit too fragile for building use; more like solidified smoke than a blanket.
Specifically the piece holding up a brick, and the section: "Despite the fact that it is prone to shattering, it is very strong structurally. Its impressive load bearing abilities are due to the dendritic microstructure, in which spherical particles of average size 2–5 nm are fused together into clusters. "
Just because it looks fragile, doesn't mean it is. Things start to behave oddly when they have meaningful nanoscale structure
...Have some pictures :D http://stardust.jpl.nasa.gov/photo/aerogel.html
Please tell me you did a cost analysis that takes into account:
- Potential saving on heating?
- Potential expenditure on cooling (insulation and triple-glazing sound like a hot-summer to me)?
- Potential damp / humidity problems? (Aerogel is hygroscopic)
- Initial cost (including specialist builders willing to die of lung cancer and tools you wouldn't normally need to use) vs recurring savings?
- Replacement / maintenance costs if that stuff starts to fail in any way (e.g. damp, temperature-triggered flexing, or harbouring bacteria - some aerogels shatter under sharp stress, etc.)?
- Time, effort, money involved in tracking down materials and delivering.
Like just about every "green" project I've ever seen, over the lifetime of the product you'll cause many times more damage to your wallet / environment than you would have if you'd just slapped a bog-standard insulation up or left it alone.
If you do something green and it ends up costing you more money in total than the non-green alternative, chances are it's not gonna do what you think (e.g. mercury etc. in CFL, or solar cells that take more than their operational lifespan to pay for themselves - let alone anything caused by their manufacture).
Interesting stuff - I'd always thought after seeing pictures of Aerogels on the Interwebz that they were as soft as cotton wool and not 'dense' enough to be a good insulator. But what a great idea! I have a 1930's terrace without any kind of cavity wall insulation, so have been toying with the idea of having a second internal wall built with insulation sandwiched between.
I too am interested in the condensation issue as mentioned above, look forward to see some updates. Its a shame you've not got before/after temperature stats.
Comparing aerogel with K17 you said it's twice the performance and then said with a big discount you did the room for £1500 as opposed to £170 with K17.
I'm all in favour of saving energy but comparing the £1500 with the cost of energy to heat the room, how long before it's cost is offset by the fuel saving?
Or you could loose another 4cm per wall and spend almost a tenth of the money... I think most people would find alternatives to aerogel when the bill came in.
Quite, the author mentioned on the first page it was 'several times' the price of similar building materials - it wasn't until the second that we found out it was really almost 10 times the price!
The author mentioned that this ended up not being a significantly major cost in the overall balance of things, but he 'had the builders in' to do up one room!
The points I took away from this article:
* Space shuttle has insulation
* You can use this insulation in houses
* It costs ~9 times the cost of equivalent materials
* Builders don't know how to use it yet
* If I work in IT for a City firm long enough, I can be pretentious about 'green tech', and hire builders to install 'space installation' on my house, making me the most important grauniad reader in the street.
They aren't air tight, you'd suffocate, they are well sealed and have low natural air movement, which normally means that they are supplemented with a mechanical ventilation system, often run through a heat exchanger with a bypass.
So in the winter you loose little heat through air movement, and in the summer you push warm air out and pull ambient air in, if you've thought about it, you pull the air in through a ground source heat exchanger (long pipe under ground) and it comes in at 10 degrees C all year around, free heat in the winter (when the ambient air is <10) and free cooling in the summer (when the opposite is true).
So, basically what you're saying is that it's far better to go out and partake of healthy outdoor pursuits when someone in the house has been on the pulses and brown rice the night before?
Now how 'bout some more beans Mr Taggart?
ok so if the dust is a desiccant, is the aerogel itself? how does it react with humidity / condensation from breath? does it decay with humidity? do its properties change?
...but, in the end, is it worth it just to feel that you are not causing as much CO2 as the next person. How long will it take to make back the cost of all the materials and time?
Those PV panels you have cost how much and yet, given the British weather, actually end up producing how much electricity? And of course, you factored in the cost in CO2 to actually make them in the first place?
It's all very well sealing our homes, we could live in a plastic box if you wanted to but the reality is that humans and the materials and furnishins in most homes actually need a bit of fresh air... I've lost count of the number of stories I've read about well meaning individuals who insulated themselves in so much in the vain attempt to stop 'global warming' that they ended up in a house dripping with condensation and then had to run dehumidifers all day to get rid of it.
Personally, I'm willing to trade a little insulation value and accept heat loss in exchange for proper airflow throughout my house.
But the problem is more with folks who know enough to be dangerous (DIY'ers) but don't know proper building technique. As indicated elsewhere in the comments, taking an existing structure with little to no insulation and then trying to insulate the bejeezus out of it can actually cause more problems than it resolves - especially around ventilation and condensation/mold.
I still think aerogel is still interesting for translucent window applications (would be curious to see how outrageous the prices are) but for wall insulation this really just confirms, for me at least, that there are much better options/approaches out there. That said, if I ever need to try and insulate a structure with a razor thin envelope and money is no object... I might follow the author's lead (although I would give more time/thought to the condensation issue).
... is this stuff any good for sound insulation as the party wall in our house is letting through far too much noise from next door, I suspect it's because the brick walls are only 2skin width and laid at their thinnest point.
...there are specialty sheetrocks (in the US/Canada at least) with sound insulation built into them. I think there is a Holmes on Holmes episode where he used one of them. I don't recall any of the names off the top of my head, but a search should find a whole lot of info on various approaches and product choices (easiest, IMO, from your post being the sheetrock).
Sorry I can't answer your question on the aerogel - I have no clue on it but it doesn't seem consistent with any of the established sound reduction methods I've seen.
This problem can caused by e.g. structural timbers that run through the wall, or gaps around them, so it's worth investigating further before you assume that a whole-wall treatment will be cost-effective. Also sound insulation has different requirements than noise insulation - e.g. a stud wall with rockwool and double plasterboard can be very effective if it's isolated from vibration from the existing structure, and a lot cheaper than specialist material.
Seems a bit expensive, but it could be amortised over time given that energy costs are bound to rise.
Excellent article! I was unaware that aerogel had any purpose beyond aerospace.
Couldn't decide between the "artificial fire" or the "getting coat" icons.
"we were able to replace two large old and ineffective radiators with one half-size double-skin"
ALL radiators are 100% efficient and are rated in BTU's relevant to the surface area available that the water flows through.
If you are saying that you replaced 2 x 1 kw radiators for 1 x 2Kw radiator that is half the physical size then i'm with you.
If not, i don't get it!
He didn't claim his old radiators were less than 100% efficient. Just that with his old insulation, they were ineffective for heating his room.