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In the future (based on present/emerging tech) someone builds what is effectively a mountain bunker to survive a nuclear winter. But bunkers don't have natural light. So, the plan is to build a bunker into a mountain, and have the top (maybe side too, depending on orientation and position of bunker in relation to shape of mountain) of it glass, because sunlight is nice. But normal glass is a bad idea.

I'm curious about the possibilities and properties required to make this idea viable (even if just theoretical). For example, I am aware that manufacturers can create thick lead glass which shields from intense radiation. I am also aware that this would be heavy, and am not sure how easily it could be damaged. So what designs would be necessary? Geodesic domes? Or could the glasshouse be made into any shape? Using materials like graphene to reinforce the glass and structure, to prevent feral humans from smashing it?

Could such a glasshouse top be reinforced to the point it is resistant to intense radiation, boulders, battering rams, small arms, bombs? If not, what options are available, or theoretically would be required? Given that bullet/bomb proof glass, and radiation proof glass, are available.

Also, with regards to how useful this would be; could plants be grown under the glasshouse of leaded glass? And could the glass be heated automatically to melt any snow? Would the radiation proofing make it impossible to grow plants under it?

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  • $\begingroup$ wouldnt be easier to just stick a bunch of solar tubes in there rather than a glass dome? Plants can be grown in sealed ecosystems... $\endgroup$ – Erik vanDoren May 20 '16 at 14:00
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    $\begingroup$ Just add shutters to your windows. $\endgroup$ – Burki May 20 '16 at 14:09
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    $\begingroup$ Welcome to the site, I like the question and am not sure I understand the negative response you are getting. I would remind others that the expectation is answers should accept the premise of the question unless the premise is not internally consistent. The setting being developed here is interesting and has merit even if it isn't entirely practical or the easiest way to do things. $\endgroup$ – James May 20 '16 at 14:12
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    $\begingroup$ @James, staying within a question constraint is the fun of WB, but its asked about possibilities and properties to make a non viable idea viable. I dont think its wrong to answer "not possible" to something when the question constraints make it so. Its needed a "glasshouse top be reinforced to the point it is invulnerable to intense radiation, boulders, battering rams, small arms, bombs" with today tech...no such material... A question asking "which material able to pass sunlight and resist <list> could I use for a fictional bunker" is one thing, "mountain top" is another question $\endgroup$ – Erik vanDoren May 20 '16 at 14:40
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    $\begingroup$ Today we have glass which is radiation proof, we have glass which is bullet proof, bomb proof. And there's a lot of new materials which can produce incredibly strong reinforcement (like graphene). "can't be done" isn't true, in so far as the individual tasks can be achieved. At least, if the sum is impossible I'd really like to know why, and what theoretically could make it happen, rather than just "oh well it's impossible". $\endgroup$ – inappropriateCode May 20 '16 at 15:29
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If you really insist on having natural sunlight in your mountain bunker (I agree with AndreiROM that having a combination of UV lamps and some kind of thermal electricity generators would be the preferred method), you could avoid the immensely failure-prone glass roof by building light conductors. Use fiber optics (or if you want to be old-fashioned, use tunnels + mirrors) to guide the light from the surface down to wherever you grow plants.

You won't have to worry about radiation or heat-loss issues since you have enough shielding between yourself and the surface. And, since you don't have to group all your 'light-collection' places in one spot you build hundreds and thousands of them and so can compensate more easily when several of them fail (e.g. because they got snowed in, because of material failure, because a landslide buried them).

But, just like in the case of the glass roof, you will need people who periodically go up to the surface to maintain those exit points. If you don't want to endanger your people that way, and if you don't want to be dependent on 'Does the sun shine today or is the cloud cover so thick that we get twilight at best', you are reduced back to UV lamps and a totally autark underground system.


For a glass roof, you need to consider following issue: since you only have a glass roof and no side windows, your glass house can't be too deep (otherwise, your plants would only get light at high noon when the sun is right on top of the mountain). If it isn't very deep, however, you need to invest a lot into heating the thing to a comfortable temperature for plants.

Concerning the glass -- I think it is completely feasible to have large areas spanned by it, and even that it admits enough UV radiation to let plants grow. And I also think the joining-glassplates-issue can be solved even with current technology, never mind your SciFi setting.

However, since you are building to last decades you need to consider the regular maintenance a glass roof needs, no matter whether it is a high-tech version like yours or a conventional one: its surface needs to be cleaned regularly. Gradually, dirt will build up (be it from rain that dried or particles blown in by the wind or trees/boulders falling on top of it), and it will eventually effect your glasshouse functionality. Here, too, it would be advisable to not put all eggs into one basket, so-to-speak, so that you have both a fallback in case one glasshouse breaks, and the area that needs to be glassed over is smaller.

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When building a bunker to survive a nuclear apocalypse aesthetics should really take a back seat to survivability. A huge glass dome, or wall does not equate to survivability.

A wall - of any kind - which is exposed to the elements is a liability. A wall made of glass (even super strong glass) is an even bigger liability. Maybe even a suicidal liability.

Why? It's a nuclear winter! The surface of that entire wall is going to constitute one huge area through which your bunker is going to lose heat. It's also a surface which will get heavily irradiated, and, over time, lose integrity due to the constant radiation exposure.

This bunker should be deep underground, in a location where it can access very deep underground water sources, and your sunlight issue would be solved using very high quality lamps, etc. If we can grow plants on the International Space Station your survivors will manage just fine in a bunker without a freakin' window.

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  • $\begingroup$ While this is good advice you haven't really answered the question Andrei. Remember to accept the premise of the question as written (adding notes on a potentially smarter plan as you did is always good as well, but you should answer the question because that is what the builder wants to build) $\endgroup$ – James May 20 '16 at 14:14
  • $\begingroup$ Whilst I appreciate the points you make, which are sensible, the point is to query the possibility initially stated. Consider the last sentence you used: sure they can grow plants on the ISS, but they also gave it a window. I'm also curious about the notion of lead glass losing integrity due to exposure to radiation? As I've seen lead glass used in nuclear reprocessing facilities that was presumably not intended to be replaced until the plant is closed in fifty years or so. So such glass should be able to last a long time? $\endgroup$ – inappropriateCode May 20 '16 at 14:46
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    $\begingroup$ @inappropriateCode - the ISS has some small windows, yes, but not for the purpose of the plants getting sunlight. They use UV lamps for that. As far as the "lead glass" goes: maybe the glass is 100% immune to radiation, but is the insulation around the windows immune as well? What about the walls it's set into? Concrete is 100% not immune to radiation. In power plants they perform insane amount of maintenance, and don't have to worry about "small arms, bombs", or anything else trying to break the windows. $\endgroup$ – AndreiROM May 20 '16 at 14:49
  • $\begingroup$ There was a BBC documentary presented by professor Jim Al-Khalili "Britain's Nuclear Secrets: Inside Sellafield", which I would recommend. At one point he's showing the nuclear reprocessing part of the facility, and is stood beside a thick glass window looking into the machinery which automatically melts the spent fuel into glass discs for storage. The radiation inside of that chamber would be enough to kill him pretty swiftly if the glass wasn't there, which he described as "lead glass". I don't know the technical term, for it, but it is a real thing. $\endgroup$ – inappropriateCode May 20 '16 at 15:25
  • $\begingroup$ @inappropriateCode - I am not disputing the existence of lead glass, what I'm saying is that the setting in which you use it is very important. $\endgroup$ – AndreiROM May 20 '16 at 15:36

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