Galvanized roof was at least laid in 1952 or earlier

[Tom M King]

Yes, I saw that. It could well have been made sometime in there, and sat in inventory somewhere, for some unknown amount of time. In any case, 1875 has to be out.

Still curious how stiff the metal is. The only corrugated roofing I've ever seen like that was pretty thick, and stiff. It was still sold in farm stores, around here, in the early 1980's.

edited to add: All the old carpenters that were working for me in the early 1980's, were still using Yankee screwdrivers. I bought the first impact screwdriver they had ever seen-a Rockwell 7563 (if I'm remembering the model number correctly-edited: looked it up, and that's the wrong number). None of them liked using it, to start with. One said, "If that thing knew when to quit, it might be okay", after ringing the head off of a #12 wood screw, back when wood screws were still sold, and some good.

[Nicholas Lawrence]

Could be a lot number or something.

I have a tar and gravel roof. Cannot find anyone around here who knows anything about them. Older gentleman at the building supply store told me to look at it every year, and put a little roofing cement and new gravel down if bare spots appear, and he said it would last forever.

Personally I like the standing seam roofs like what was mentioned are common on older houses. Painted or not they seem to last forever.

[Tom M King]

Once a Terne coated roof starts rusting, it's not long for this world. They typically painted them with a linseed oil based paint, which would have to be repainted every couple of years.

My Grandfather's house had it. I don't know of any that lasted over 100 years, and usually not over 50. The last one we replaced was 36 years old. I still see some from the mid 20th Century, but those are on abandoned houses around here, and most likely leaking.

I put a copper standing seam roof on a house I built in 1991. That one should be around for a while. It cost 63 cents a square foot for materials then. 10 dollars now. I was considering putting Terne coated on it, but the break even point was the second time the Terne had to be repainted.

I don't think you can even buy Terne coated metal now. Follansbee steel went out of that business.

[Kevin Jenness]

My dad bought me a Yankee screwdriver- it's been a long time since I used it, but I do have a 1/4" hex drive adapter in it just in case. I have one for a bit brace too which gets used occasionally.

A guy I worked for called them "project destroyers" for the result when the spring-loaded bit slipped off a slotted screw and scarred the work.

[Nicholas Lawrence]

My dad bought me a Yankee screwdriver- it's been a long time since I used it, but I do have a 1/4" hex drive adapter in it just in case. I have one for a bit brace too which gets used occasionally.

A guy I worked for called them "project destroyers" for the result when the spring-loaded bit slipped off a slotted screw and scarred the work.

My grandfather took the spring out of his. I never got to ask him why, but that may be it.

[Malcolm Schweizer]

Yes, I saw that. It could well have been made sometime in there, and sat in inventory somewhere, for some unknown amount of time. In any case, 1875 has to be out.

Still curious how stiff the metal is. The only corrugated roofing I've ever seen like that was pretty thick, and stiff. It was still sold in farm stores, around here, in the early 1980's.

edited to add: All the old carpenters that were working for me in the early 1980's, were still using Yankee screwdrivers. I bought the first impact screwdriver they had ever seen-a Rockwell 7563 (if I'm remembering the model number correctly-edited: looked it up, and that's the wrong number). None of them liked using it, to start with. One said, "If that thing knew when to quit, it might be okay", after ringing the head off of a #12 wood screw, back when wood screws were still sold, and some good.

To bend the material, you really have to be trying to bend it. It is like a car fender. I mic’d it at 1/64th inch.

[Tom M King]

That gives me another reason to think that it's not that old. If it has a fairly high carbon content, the faster it rusts away. I can't believe that any tin roof would last as long there, as the same thing here would.

It looks very much like a tin roof on an observatory that my friend, and I built in 1967. That was a very steep roof, and it's been rusted away for some years now, although the little building is still mostly standing.