Monday, March 28, 2011

Foundations.

No, not foundation garments. The actual foundations of buildings! (All photos are mine except for the one at Fort Pitt and the last one.)

When we were shopping for our house, being me, I read a couple-ten books on architecture, home building, building materials, and like that. It gave me a great background for looking at houses, but it also helped me know what I was looking at, in places I never intended to buy anything.

We're in an area that's been settled since the 1700s. So it's not uncommon to see a beautifully restored building, but when you take a good look at it, you see stuff like this:
Namely, original foundations of buildings, cobbled together out of gods-know-what. So, being me, I started poking at the history of things.

There were fur trappers in the area back in the 1660s, but it wasn't until the French built a fort in the 1750s that the area was stable enough to settle in a serious way. I'm sure the first shelters (I can't call them houses) were relatives of tents or extremely rustic log cabins built right on the ground, and they haven't survived. When first settling an area like this, Europeans were too busy trying to live though cold and heat and panthers and finding food to expend much effort on fancy buildings. The oldest surviving building in Pittsburgh is part of Fort Pitt built in 1764:
If you can see it, it's cobbled together with rocks. Some are dressed (smoothed into a brick shape of some kind) and some aren't. Back then, they were building with whatever they could scrape out of a river bed or hillside. They favored sand stone (it's soft enough to work with a hammer and chisel, which is about all they had) and shale and slate - both of which break in smooth chunks. You wind up with something like this:
This is from a place closer to my house, also built in the 1760s. It's kind of interesting; the back walls are built like this, with random rocks, but the front of the house is dressed stones:
So in the 1760s, dressed stone was still a good bit of trouble to go to.

Larger, heavier buildings like barns were also built in a 'compound' sort of way - the corners of the foundation are built up with super heavy, solid, dressed stones, and timbers were run from corner to corner to corner. The timbers support the upper portion of the building, and then the rest of the foundation walls were filled in with anything they could find in terms of stones. Most around here (no good pictures, sorry) look like they were done with slate or shale - I don't envy them the job. Even way back, builders realized random rocks weren't enough for load-bearing, and hauled in the good stuff for that. But they didn't haul any more than they had to. Considering they were using horses, block and tackle, who could blame them?

The problem with the 'pile of rocks' building method is the cement. (At least, here where I am. Different parts of the world have different problems.) Because the sides of the rocks aren't parallel, the cement is required not only to anchor the stones, but also to fill in uneven spaces and bear a lot of weight. And this was at a time and place when cement-making was done in people's back yards or a quarry, by people who didn't exactly have PhDs in materials engineering. (I'm talking about actually making the cement, not mixing it together.) So, many of the houses around here have either had entirely new foundations built for them, or have had all kinds of re-mortaring done.

Travel - and therefore shipping any kind of building materials - between civilization (East Coast) and the Pittsburgh area was problematic for many years. You could either go by land in a wagon (through malarial swamps, freezing mountains, and over horrific roads), or by river (also malarial) which required a trip through New Orleans and up the Mississippi. Because of that, building materials were still on-the-spot productions, so everything in this area was stone, wood, and sketchy mortar. In 1834 a canal and rail line went through from Buffalo to Pittsburgh, and in 1854 rail travel from Philly to Pittsburgh became possible. After that, shipping in cement became easier and the quality of buildings went up steadily. I'll bet you this area produced better window glass than cement, for a couple decades at least. It's all in what kinds of raw materials were laying around.

In fact, due to the raw material situation, there was a thing sort of like a cinder block made, that is in fact a type of stoneware/ceramic:
They're actually pretty good at load-bearing and were used for decades until being phased out by cinder block. Sort of. I bet they're still on the market. Of houses built before WW2, I bet 1/3 or more have foundations of these types of block. In this area, anyway. (We've got lots of clay and the stuff to make glaze.) See the coal chute? Love old houses.

Bricks of course seem obvious to us as a building material. But the problem for a long time was transporting them, not making them. Here in PA, even with railroads, getting the bricks from a rail line into the valleys and hills to a building site was still brutal. Since this area is full of clay and gravel and other brick-making materials, they made a lot of them right on the spot.
Which led to a lot of buildings settling weirdly and otherwise slowly disintegrating because the bricks weren't fired right. See the patching being done between the first and second floor windows? Bricks need to be fired at about 1750F/950C to properly bear weight later and not gradually turn to dust. That's not a temperature you're going to produce with a wood fire out in your back yard, or at least not easily - not to mention, the temperature needs to be held steady for a while or, yeah, they slowly turn to dust again.

So, even though the valleys here are full of clay, bricks were still pretty tricky to make and build with.

Cinder blocks, our current go-to for building foundations, is a fairly new invention. Especially the mass-production of them. But like so much else, the real problem with cinder block isn't really making it - it's transporting the damn things. They came into 'common use' in the 1920s along the east coast, and from the looks of it around here, were used here since about the 1930s. But, just a decade ago, I remember hearing a friend in the building supply biz in Hawaii telling me about a shipment of cinder blocks coming in with a 50% breakage rate. That was about normal. Those suckers are oddly fragile.

Now, with the whole world of building supplies available, people who can afford anything, what do they do?


They build with barely dressed stone.

People are so damn weird.

12 comments:

Caryn said...

They build with barely dressed stone so it will look like it's been there forever.
Around here we get a lot of field stone foundations. In very old houses they are flat-ish field stones that are stacked. I don't know if there is mortar anywhere in there. In post Civil War houses like mine, they are round-ish boulders that are mortared. Fun job repointing those things.

Alwen said...

Speaking of brick, I'll bet you'll like this website I just found. For example, their article on Hoffman kilns (ring-shaped brick kilns):

http://www.lowtechmagazine.com/2009/10/hoffmann-kilns-brick-and-tile-production.html

Lots of other cool stuff on there.

missleya said...

You'd probably find cement slab foundations interesting too, the possible history behind them and their upkeep.
(Used in TX, not sure where else, likely somewhere.)

Barbara said...

Here in the upper Midwest, where there's lots of clay, poured concrete foundations work well. Concrete block shifts and weeps making wet basements. Lots of historic homes have stacked limestone foundations and fences, and farmhouse foundations are made from fieldstone which the ground around here, where the glaciers visited, grows with abandon.

almeda said...

In Chicago, a lot of older stick-construction houses has fieldstone foundations and crouch-over crawlspaces until the mid-80s, when there was a boom in jacking up the houses and pouring a new cement slab-and-foundation-walls to make stand-up, finishable basements (that also didn't need nearly so much pointing/maintenance).

I happen to know this because my mom was a contractor at the time, and specialized in doing houses that were occupied while jacking (most contractors wanted you to move you and all your belongings out for a month while they did the construction).

Roxie said...

For a period of time, contractors around here were doing poured slab foundations with radiant hot-water pipes built in. Then came an icestorm, the power went out, the water in the pipes froze, and, well, you can imagine the disasters. When shopping for houses, I, too have paid careful attention to foundations.

Ellen said...

Have you checked out Old Economy Village in Ambridge, PA? German precision building in the 1830s. Or some of the houses in Harmony, PA? 1815 or so. The Harmonists built kilns wherever they went and then built out of bricks. Very cool!

For the early stuff, stop by Fort Macintosh in Beaver, Pa. - my hometown. The last fort on what was the frontier prior to the Revolutionary War. In ruins now but very cool foundations.

Grew up in WPA and miss some parts of it very much!

Liz said...

Foundations? oh yes, people have those, don't they; elsewhere. Here on the edge of the English Fens, my little house is on about a foot and a half of brick. It's amazing it's as square as it is.

Meanwhile, friends who actually live ON the Fen have a timber-framed house sitting on 18-foot pillars driven into the mush...

Allison said...

You might enjoy this movie: http://www.imdb.com/title/tt0255313/

The write-up talks about coping with loss and being a role model but there's lots of interesting details on making bricks by hand.

Alicyn said...

those nominal 8"x16" cinder blocks (aka concrete masonry units) are brittle on their own, but can resist quite a load when properly filled with steel rebar and poured concrete.

Amy Lane said...

See-- that is just so cool! Alas, there very few old buildings in California--the Gold Rush buildings (our first) were mostly canvas--and burnt down quickly, or didn't survive the flooding. (Sacramento is built on about four-five feet of river-bottom silt, imported through the years as the place flooded and was rebuilt.) One of the oldest buildings that I've seen is in Foresthill, and the reason it's still around is that the roof is about three feet of sod. (It has three tunnels--one from the place, which was a mail repository for a while to the owners house, and two from the front door--one leading to a brothel and another one leading to a secret entrance from the street.) I'll have to take a look at what it's made of, besides old dry-goods shelves and oar cart planks on the inside, as well!

Leah said...

We on the West Coast don't build with brick. Brick has a disconcerting way of turning to powder in an earthquake. Wood frame houses have a way of gracefully swaying during an earthquake, and not comming down squish quite so badly as brick or rock. People long for the solid look of rock and brick, so face their timber frame houses with them. I find it weird to see the facing end at the corner of the house.

Some of the oldest houses were put on a stack of rocks; nothing mortared at all; the wind blowing under the house. It doesn't get that cold here, so it worked ok. The people restoring the houses jack them up, clear out, and pour concrete.

It is interesting how where you are effects what is built.