[Greenbuilding] The five hundred year house

[Chris Green]

Andy Foldes wrote:
> Please forgive if this has been discussed already, I have not been here that
> long. In my own musings about someday building a house, I am inclined to
> imagine it as a structure that will last centuries. While that may strike
> some as bizarre, it seems quite obvious to me, having traveled enough to see
> people very happily living in five hundred year old farmhouses or palazzos
> in southern Italy built in Michelangelo's day. 
There are some wooden buildings in Northern Europe which are over 700 
years old, but these are few and far between, and have been lucky to 
avoid fires.

A friend of mine in Peterborough, England, lives in a stone surfaced 
house that I thought looked like it might have been built in the 1880's. 
Turns out it was built in around 1645. Most of it, except what looks 
like a later addition. The walls are about 2' thick. I suspect the walls 
are rammed earth of some kind, perhaps rammed limestone, but they might 
also contain some kind of cob mix..
There are an estimated 40,000 cob houses being lived in in the UK today, 
and a goodly number of these are 400+ years old.
Another friend of mine lived in a similar to that in another part of 
England. They traced it back to about 425 years ago, but couldn't go 
back farther because the written records only went back that far. This 
particular house had a fire in it while they lived there, and the fire 
damaged the ceiling. It turned out the ceiling was deeply insulated with 
a straw/clay mix, one still commonly used in Germany, where it is called 
something like lichthelm. Your big challenge will be in convincing the 
building inspectors this will actually work. No matter, blowing in 
cellulose over top of the straw/clay mix will help things along.
> So I am curious if this topic has been studied much, and if any works have
> been written on the topic. 
The people who promote the Open Plan concept are thinking about this. I 
don't have a link to a website discussing this right handy. so maybe 
someone else might have it.
When designing an Open Plan, you start with an awareness that the uses 
of the building and the needs of the occupants will change over time, 
and so there will come a time when the interior of the structure will 
have to be changed. Bedrooms added, or removed, and so on. It might help 
to think of this as a modular type of construction. Modern office and 
commercial buildings, and some residential units, are designed to have 
the walls removed and changed around  quickly. With the advent of 
electrical wiring, this becomes a bit more of a challenge, and plumbing 
features will mean that some walls will remain in place over the years.
For a long lasting insulation, besides the previously mentioned 
straw/clay insulation, you could use rockwool.  It isn't prone to the 
problems that glass fibre is. The subsurface foundation could be 
exulated with rigid foam insulation, which I'm pretty sure will last a 
long time. Probably be around until the sun goes nova, actually...

The S.I.R.E wall system of stabilized, insulated rammed earth 
construction has rigid foam at the core of the walls, but insulation 
could also be mounted on the exterior if you work out some way to cover 
the insul boards with something like cement fibre siding (like Hardie 
planks.)
Roofing could be the traditional slate or clay tiles, but it could also 
be the newer concrete tiles. These should all rightly be fastened with 
stainless steel nails. A bit pricey, but still much less than replacing 
other types of roofing in 30-40 years.

Having wider doors at the entrances will make it easier to move stuff in 
and out of the house as time goes by. It is quite possible to design and 
build thicker doors with more insulation in their core to reduce heat 
lost thought these. No law says a door can't be 6 or 8" thick, and these 
can even be built using ferrocement techniques. (see 
http://www.flyingconcrete.com for examples.)
Hardware  (locksets ) for thicker doors will require some creativity, 
but that's part of the design challenge.

> It would be interesting to imagine how such a
> house would be built, since passive systems would seem to be the way to go,
> as opposed to the tons of machinery that keep present houses livable, but
> which would wear out in short order. And some off-grid functionality would
> have to be built in. 
Precisely. In designing and building the structure, I'd also plan for 
the day when you can add photovoltaic panels, so I have been 
recommending pre-installing the conduit pipes for the pv wiring 
circuits. Electricians I have talked to think this is a good idea, and 
it doesn't add much cost, even in conventional stick housing.

As for heating, German Passive Solar House design guidelines might be 
good to look up and refer to.

Lastly, a minor detail for long term planning.  I'd also build the house 
a bit higher off the ground. Why? In the really old houses in Europe, 
you now have to step down one or two steps to enter the houses, which 
used to sit at grade. Earthworms in the soil create more soil as time 
passes, and after 4-500 years, they can have raised the grade a couple 
of feet. This is why the Roman era villas in Britain are 4 and more feet 
below the top of the soil. Raising the foundation up a bit and sloping 
the soil away from the building will also will help avoid the flooding 
being seen in the Wisconsin and Minnesota this week. And if your site is 
kept healthy, the worms will be happy doing what worms do.

Anyhow, a 500-year house is quite doable. So too is a 1,000 year house, 
I think.

Cheers,

Chris Green.