# What is the oldest material in a modern house **URL:** \ **Category:** Factual Questions\ **Created:** [November 27, 2019, 8:23pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085 "2019-11-27T20:23:11Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Nansbread1](https://avatars.discourse-cdn.com/v4/letter/n/6a8cbe/32.png) [@Nansbread1](https://boards.straightdope.com/u/Nansbread1)\ **Post date:** [November 27, 2019, 8:23pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/1 "2019-11-27T20:23:11Z")
Take a modern brick house in any European or US state. What will be the oldest material in the house, if you exclude private possessions. The bricks, the door, the lead flashings, the copper pipes, the wooden floors, the glass, the roof… Is there something that houses are made of that clearly trumps all of the above as having been on planet earth earlier than anything else in the structure of the house. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [November 27, 2019, 8:25pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/2 "2019-11-27T20:25:09Z")
The wood structure? ---
**Author:** ![PatrickLondon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/patricklondon/32/4422_2.png) [@PatrickLondon](https://boards.straightdope.com/u/PatrickLondon)\ **Post date:** [November 27, 2019, 8:31pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/3 "2019-11-27T20:31:06Z")
The clay the bricks are made of? Or (at least in much of northern Europe) the slates on the roof. ---
**Author:** ![puzzlegal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/puzzlegal/32/3827_2.png) [@puzzlegal](https://boards.straightdope.com/u/puzzlegal)\ **Post date:** [November 27, 2019, 8:31pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/4 "2019-11-27T20:31:35Z")
It depends how you count. The sand in the mortar might be ancient. Are you counting when the mortar was made, or when the parts that made it were gathered, or when the sand was created? Are you counting a wooden door form when it was formed into a door or from when the tree grew? I’d think if you are counting from when the item was made into its current form, most of the parts of a house would be just a little older than the house. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [November 27, 2019, 8:34pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/5 "2019-11-27T20:34:39Z")
Diatomaceous Earth, if you have a filter that uses it. It’s the fossils of ancient diatoms. As the link below notes, some of it dates back to the Miocene, 12-13 million years ago (although the Miocene stretches back much older than that. Maybe some of the diatoms do, too) > **[Diatomaceous earth](https://en.wikipedia.org/wiki/Diatomaceous_earth)** > > Diatomaceous earth (/ˌdaɪ.ətəˈmeɪʃəs/ DY-ə-tə-MAY-shəs), diatomite (/daɪˈætəmaɪt/ dy-AT-ə-myte) or kieselgur/kieselguhr is a naturally occurring, soft, siliceous sedimentary rock that can be crumbled into a fine white to off-white powder. It has a particle size ranging from more than 3 μm to less than 1 mm, but typically 10 to 200 μm. Depending on the granularity, this powder can have an abrasive feel, similar to pumice powder, and has a low density as a result of its high porosity. The typica... ---
**Author:** ![harmonicamoon](https://avatars.discourse-cdn.com/v4/letter/h/65b543/32.png) [@harmonicamoon](https://boards.straightdope.com/u/harmonicamoon)\ **Post date:** [November 27, 2019, 8:35pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/6 "2019-11-27T20:35:45Z")
Sheetrock? I don’t know which is older. Sand for cement or rocks made into sheetrock. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [November 27, 2019, 8:48pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/7 "2019-11-27T20:48:03Z")
> [@CalMeacham](#): > > Diatomaceous Earth, if you have a filter that uses it. > > It’s the fossils of ancient diatoms. As the link below notes, some of it dates back to the Miocene, 12-13 million years ago (although the Miocene stretches back much older than that. Maybe some of the diatoms do, too) > > [Diatomaceous earth - Wikipedia](https://en.wikipedia.org/wiki/Diatomaceous_earth) If the sand contains fragments of ancients rocks such as zircons they could potentially be billions of years old. ---
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [November 27, 2019, 8:51pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/8 "2019-11-27T20:51:59Z")
I’d guess pure elemental material, particularly metals heavier than iron, since they would be formed in (as I understand it) neutron-star collisions, and thus must predate the Earth. So the copper pipes are a good candidate. ---
**Author:** ![pmwgreen](https://avatars.discourse-cdn.com/v4/letter/p/edb3f5/32.png) [@pmwgreen](https://boards.straightdope.com/u/pmwgreen)\ **Post date:** [November 27, 2019, 9:02pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/9 "2019-11-27T21:02:24Z")
Granite countertops? ---
**Author:** ![am77494](https://avatars.discourse-cdn.com/v4/letter/a/d2c977/32.png) [@am77494](https://boards.straightdope.com/u/am77494)\ **Post date:** [November 27, 2019, 9:05pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/10 "2019-11-27T21:05:03Z")
> [@Nansbread1](#): > > Is there something that houses are made of that clearly trumps all of the above as having been on planet earth earlier than anything else in the structure of the house. Hydrogen and helium are the oldest elements in the universe. Water is made up of hydrogen and anything containing water would be the oldest. So things like water in wood (about 30%), in mortar , in bricks, … ---
**Author:** ![casdave](https://avatars.discourse-cdn.com/v4/letter/c/c6cbf5/32.png) [@casdave](https://boards.straightdope.com/u/casdave)\ **Post date:** [November 27, 2019, 9:27pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/11 "2019-11-27T21:27:17Z")
I would imagine slate is pretty old as a construction material in its own right, rather than an amalgam such as mortar. Lots of houses will have stone lintels and mullions. ---
**Author:** ![Jackmannii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackmannii/32/311_2.png) [@Jackmannii](https://boards.straightdope.com/u/Jackmannii)\ **Post date:** [November 27, 2019, 9:51pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/12 "2019-11-27T21:51:13Z")
In a closet I have some mono records of Toscanini conducting the NBC Symphony Orchestra. Does that count? ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [November 27, 2019, 10:21pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/13 "2019-11-27T22:21:07Z")
The Welsh slate on my sister’s house roof is supposedly 400 million years old. [https://www.geolsoc.org.uk/ks3/gsl/education/resources/rockcycle/page4008.html](https://www.geolsoc.org.uk/ks3/gsl/education/resources/rockcycle/page4008.html) ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [November 28, 2019, 12:19am UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/14 "2019-11-28T00:19:34Z")
> [@Sailboat](#): > > I’d guess pure elemental material, particularly metals heavier than iron, since they would be formed in (as I understand it) neutron-star collisions, and thus must predate the Earth. > > So the copper pipes are a good candidate. Most Elements heavier than iron are formed in Supernovae. Gold is formed in neutron-star collisions. ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [November 28, 2019, 12:36am UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/15 "2019-11-28T00:36:37Z")
> [@pmwgreen](#): > > Granite countertops? Probably. Lots of precambrian granite. If you go with elements, if the house has any type of storage batteries (for solar or whatever) the lithium goes back to the Big Bang. ---
**Author:** ![Banksiaman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/banksiaman/32/3334_2.png) [@Banksiaman](https://boards.straightdope.com/u/Banksiaman)\ **Post date:** [November 28, 2019, 2:54am UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/16 "2019-11-28T02:54:24Z")
Many houses in the Sydney Basin, which covers a population of maybe 5 million people, incorporate local sandstone blocks as footings or even wall structure. It was formed in the earliest Triassic, so a quarter of a billion years ago, in round figures. Unlike some of the material cited, its still pretty much just what it looked like back then, only cemented. Of course its constituent quartz sand and other particles are older still. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [November 28, 2019, 8:55am UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/17 "2019-11-28T08:55:32Z")
Going by “material” as being a composite substance, rather than the elements or individual minerals that comprise it, I think it’s going to be rocks of some form, if the house has any. Even concrete will usually have rock in it as aggregate - recycled aggregate exists but ins’t the norm - millions of tons produced vs billions for crushed rock. And unaltered rocks are millions to billions of years old, nothing else is going to come close - the metal alloys will all be recently smelted, ditto the glass, and the same goes for porcelain and bricks, even the clays will be fairly recent alteration products of older rocks. The oldest possible wood can only be a couple thousand or so years old (and most lumber will be less than a hundred). I’m not that familiar with US construction - can a modern brick house not use any concrete? I would think it would require a poured foundation at a minimum. So it will have million-years-old rocks in the aggregate. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [November 28, 2019, 8:58am UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/18 "2019-11-28T08:58:02Z")
> [@harmonicamoon](#): > > Sheetrock? The gypsum used for sheetrock is a manufactured product. The raw material may be the older gypsum rock, but it’s completely changed by the time it’s incorporated into the drywall. ---
**Author:** ![Novelty\_Bobble](https://avatars.discourse-cdn.com/v4/letter/n/a3d4f5/32.png) [@Novelty\_Bobble](https://boards.straightdope.com/u/Novelty_Bobble)\ **Post date:** [November 28, 2019, 11:22am UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/19 "2019-11-28T11:22:24Z")
If you consider the various constituent parts of a building and set an arbitrary requirement that is a material used in its original form and structure (so it can be physically shaped but not amalgamated or otherwise processed) then for houses I’m familiar with, probably slate (\>500 million), sandstone (\>700 million), limestone (\>200 million) or flint (\>75/100 million). Those figures will of course vary from location to location. ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [November 28, 2019, 2:02pm UTC](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085/20 "2019-11-28T14:02:03Z")
> [@bob\_2](#): > > The Welsh slate on my sister’s house roof is supposedly 400 million years old. > > [Geological Society - Slate, North Wales](https://www.geolsoc.org.uk/ks3/gsl/education/resources/rockcycle/page4008.html) Whoa. I was impressed with our shingles 50 year warranty. [Next page](https://boards.straightdope.com/t/what-is-the-oldest-material-in-a-modern-house/844085.md?page=2)