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How long ago were 2×4 actually 4 inches?

AlanB4 | Posted in General Questions on

I live in a very old house in Ontario Canada and its built with actual 2x4s, i have no idea how old the house is so i’m hoping to get some idea by finding out when 2x4s were shrunk and assuming the house was built before that.

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  1. Expert Member

    Alan, Unfortunately there is no reliable way of fixing the date of a building by sizing the wall studs. You will have much better luck looking at the architectural style or, as most towns in Ontario have very good archives, checking for references to it or it's neighbours there.

  2. Expert Member

    Allan, Could you post a picture? We might be able to estimate based on the style. Which town?

  3. AlanB4 | | #3

    I would prefer not to post that kind of personal information, i apologize

  4. AlanB4 | | #4

    I've tried what i can think of, its balloon framed, brick basement walls, made with barn board walls, its the first time i have seen plaster-lath-plaster,barnboard (1.5in thick barnboard), 2x4, (no exterior sheathing) exterior wood siding and vinyl siding (added on top about 10 years ago)
    I have not pursued it seriously, i could spend time at the library going over very old records and maybe find some historians but thats a lot of effort which i don't really want to go through

  5. GBA Editor
    Martin Holladay | | #5

    The answer to your question varies from location to location. In general, homes built before World War II were likely to be built with rough-sawn full-dimension 2x4s. During the late 1940s or early 1950s, builders in many areas of North America switched to planed 2x4s that measure 1.5" x 3.5".

    Here in rural Vermont, builders are still sometimes building new homes with rough-cut full-dimension 2x4s (or, more commonly, 2x6s) cut on a bandsaw mill. I built several homes like that in the 1980s.

  6. AlanB4 | | #6

    I see, mine are rough sawn and of course old. Any idea why they would have used barnboard then plaster then lath then plaster again and no exterior sheathing?
    Also was there a time when brick foundation walls were in general use or is that also variable?

  7. GBA Editor
    Martin Holladay | | #7

    Q. "Any idea why they would have used barnboard then plaster then lath then plaster again and no exterior sheathing?"

    A. It was fairly common for older wood-framed buildings to have siding installed directly on the studs, without any intervening sheathing. It's fairly common to see stucco-clad buildings in California without any sheathing, and clapboard siding was often installed directly on the studs in many older wood-framed buildings in the Northeast, especially in rural areas.

    It sounds like your house was built with attention to air sealing. The combination of materials you describe -- interior boards, plaster, then lath and a second layer of plaster -- makes for a fairly airtight interior finish surface.

  8. GBA Editor
    Martin Holladay | | #8

    Q. "Was there a time when brick foundation walls were in general use or is that also variable?"

    A. I'm sure that the demise of brick foundations happened at different times in different areas. Certainly, a house with a brick foundation was built before World War II. I'm going to guess that the heyday for brick foundations was 1890 to 1935.

  9. Expert Member

    Allan, No need to apologize - I wasn't thinking of the privacy implications. Quite understand.
    Hope this is of some help:

  10. kshenefiel | | #10

    When planed 2 x4 studs first came into use they were 1 5/8 by 3 5/8 they switched to the current size sometime after the early 1950's, . Other tips on age. The modern round wire nails began replacing square cut nails shortly before 1900. Between 1850 an 1870 sawmills retooled from up and down saws to circular saw. So check your rough sawn boards. Up and down saws leave straight lines nearly perpendicular to the board. The marks of a larger circular saw will look nearly straight on a small board but will run across at a noticeable angle..
    The interior boards may have been an experiment in putting the sheathing on the interior so it could double as lath. with the additional lath and plaster added after they had trouble wit the plaster sticking. Or could your house have been converted from a carriage house? Rough sawn boards would have been a common interior finish for such a building.

  11. AlanB4 | | #11

    Hi Kevin, i have attached a few photos, they are the best my phone can take, i can dig out the camera if need be, i found some flat nails when i was removing the fiberglass in the headers for the cellulose, so i assume that is what the house is made of
    The house appears to have been originally 3 rooms (living and two bedrooms now) and an extension with crawlspace was added later (also made the same way except for one partial wall, barnboard-plater-lath-plaster, entire house balloon framed)

  12. AlanB4 | | #12

    Thanks for the replies Martin and Malcolm, when i moved in the blower door registered 17.68ACH50 (i have a crummy crawlspace) and with a few repairs i am now at 14.85ACH50 so i have a lot to do still, but i do hope that once i airseal the ceiling and dig out and poly the crawl i should have it reduced quite a bit. I found some newspapers from 1976 which is when it appears they installed the heavy metal chimney through the middle of the house, put wood on the "headers" in the basement (but not crawlspace) and did some other upgrades.

    At what ACH do i need to consider an HRV (i also have a gas cooking stove and chimney vent water tank, furnace was replaced with 95.5AFUE with intake and exhaust 6 months ago).

    Another question i have been meaning to ask is how vapour permeable is plaster and lath, these days i doubt it matters but if i ever do the exterior insulation (if i win the lottery first) it might become relevant. At this point i doubt i ever will, according to Hot2000 if reduced to 7 ACH50, and insulate the attic and basement (i am considering spray foam directly on basement brick if thats safe to do) the heat load will be down to 24250BTU at -20C which is just over 1/3 of what i started with

    Even more questions, what is the R value per inch of loose fill cellulose, the company i hired did it instead of dense pack so i will have to get it fixed someday.

    My house looks mostly like the victory style in that pdf file, but not quite, and i am surrounded by Regency, Edwardian, and some late Victorian.

    Last winter with the 80% furnace it was using indoor air and the humidity was at 30% and i had a hell of a time trying to raise it (i gave up), but with the new furnace i have had 50% humidity till about -10C and at -20C i am down to 30% (i get shocks every time i leave the computer). The humidifier was removed with the old furnace, but is the cause the crawlspace caused ACH (its closed but not airtight to the rest of the house) or is there some other method that humidity is being stripped?

  13. wjrobinson | | #13

    Kevin great info. I too wanted to mention the in between size with the added 1/8". I work on cabins that are built from 1900 to the present which go from full size lumber to mid size to todays standard size.

  14. kshenefiel | | #14

    Alan, Saw marks don't photograph well; but the lower part of the photo is clear enough to tell it was cut by a circular saw mill.

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