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63

Screws are a "superior" fastener over a nail (they have far superior tensile strength) - especially if you're talking about screwing down decking. However there are many scenarios where a nail is the proper fastener for the application (attaching joists is one example - screws are brittle and will fail when subjected to the forces of a shear loaded ...


28

Nails are considered an "elastic connection". They handle wood movement much better than screws. Many times if you have severe wood movement with nails you will see things like nails that tilt or seem to back out. This is actually a good thing. Many times if a screw had been used in that case it would have caused the wood to split as it moved.


19

Without looking at blueprints, all you can do is make an educated guess. Possible methods include: If it's an exterior wall, it's almost always load bearing. If the joists are not continuous over the wall (they are cut short and meet on top of the wall) it is load bearing. If there is a load bearing wall or beam directly above or below this wall, it is ...


15

According to this document (PDF), accidental notches in the top flange may not need to be repaired if they meet specific criteria. To determine if a repair is required, we'd need a bit more information, including: The distance from the center of the notch to the end of the beam. The depth of the notch. The specific beam used, including beam height. If a ...


14

The methods you describe are probably the best, but if you can actually see the wall, a load bearing wall will generally have a double top plate but a non-load bearing wall usually won't.


14

Only if you're a "professional" plumber. Cut twice as much & then measure, hey lookie there just like they did in your place. Seriously no, you're completely right the I's of I-joists are NEVER to be touched nor any holes within 3" of the top or bottom edges. "Responsible" plumbers & builders re-spec a toilet with a deeper stand-off or just pull it ...


13

I think you need to get a structural engineer out there ASAP to investigate; I would be worried too! Your city's by-law office might be able to refer you to someone who can help. It might also be worth getting in contact with your insurance company - they might have their own engineer come out. If you think it's really about to fall over you might opt to ...


13

Point your home builder to page 9 of Weyerhauser's I-joist document here. See the bottom right of the page where it says "DO NOT cut or notch flange" It is typical of all I-joist manufacturers' installation documents. As Iggy pointed out, the I-Joist in question needs to be reinforced similar to a cantilever reinforcement. To fix this, the electrical ...


12

Check if the wall is load-bearing See that link for how to do this. Try to see if there are are any high-voltage lines in the wall Look for light switches, receptacles, lights, hard-wired smoke detector In some cases, a wire may run though the wall, but not be visible. This is very hard to determine, and takes sleuth work (look for wires entering the ...


12

Good question Paul, The situation with your framing is not really normal, but not uncommon for a house that age. Any time there is separation of framing members, it is a reason for concern and should be addressed. However, I would not say it is a major or alarming problem. There could be a couple of different reasons for this separation. The joists may have ...


11

For many houses, a wall running down the middle of the house, parallel with the roof ridgeline is nearly always load bearing. You also may have easier access to the basement to check joist direction.


10

The pergola is much like a stick framed house--the framing itself resists vertical forces (gravity) but in and of itself, has no resistance to shear forces (side to side). For a house to stand up on its own, the sides need to be braced against shear forces...typically that's done with plywood sheathing. Barring that, diagonal bracing can be used. On the ...


9

Technically when using joist hangers, a specific kind of hardened galvanized nails are supposed to be used. This is because regular deck screws probably don't have the necessary shear strength. For a deck though, I've used screws before without any problem. Although if you were planning to put a lot of weight on the deck (say, a hot tub) I would be a bit ...


9

You need an engineer's advice on what the load is and what is required to support it. And no, you really can't make a mixed materials i-beam.


8

I think they're there for stabilizing the brown beams/joists. Typically, a loft is unused space with no floor. Between the joists, there is insulation supported by drywall or other material depending on the age of the house (as in pic 2 and 3). Typically one would put in blocking between joists to stop horizontal flexing and torsion. Since an attic ...


8

Nails are used in almost all framing and structural applications. Most code books are designed with nails in mind and will have specific minimum nailing requirements and patterns for different applications. Structural screws are coming more and more on the market every day, but because most code books don't include them you will need an engineer's approval ...


8

Just found this useful document (direct link to PDF) on the web. It explains in a much clear manner than I can, plus it contains some good, easy to read diagrams. Notching & Boring Guide for Floor Joists & Stud Walls in Conventional Light-Frame Construction by Western Wood Products Association


7

A properly sized floor joist should never deflect. Is your bed a water bed?. Joists are supposed to be sized to handle a minimum of 60 to 80 pounds per square foot, which is actually a lot, since loads are distributed across the entire span. If you are seeing ridges, cracks, or movement under load, you have a problem. I have seen joists wain, crack or even ...


6

If you want to install it yourself, great. But I suggest you start by having an engineer look at the application and calculate your requirements. Could be well worth the investment.


6

Probably not. For a definitive answer you can bet your house on (which you will be doing), consult a licensed civil/structural engineer. The "white post" does not fulfill the same function that the "red beam" does (making strong/rigid triangles to resist forces from the roof loads.)


6

Short answer: No. If they ring when you tap them like you did in your video, then they are solid. Sand them and paint them with a good rust inhibiting paint.


5

I agree with everything Shirlock said regarding adding joist hangers, but first I would advise you to stabilize your joists from whatever is causing separation. Edit The gaps you are seeing are not caused by shrinkage. The gaps were either there when constructed or have developed over time. On a positive note, the joists you've shown don't appear to be ...


5

There isn't enough information in that sketch to verify calculations (for instance, we have no idea what's on the floor above), but here are some reactions: Removing 60cm of support may be significant, depending on how much load that wall was carrying. If the arch is structural, removing it requires additional support. Your existing building may not be ...


5

Without destructive removal of finishes, it is impossible to know if it is a problem because the deflection of 0.625" (5/8") on a span of 14'-0" is less than the maximum allowable deflection (length/240) that has been typical in most US building codes for many years. The reality is that describing construction as 'meeting the code' sets the bar at the worst ...


5

It was probably temporary bracing used during construction. It can be safely removed once the roof structure is complete and the walls have structural sheathing properly installed.


4

Assuming the sag is new/progressing. There are countless hundred+ year old homes with proper structure that have floors that don't sag, bounce or shake. Sagging is never good. Sagging is a sign of either poor engineering to begin with or structural damage done later. bcworkz does raise a good point about older foundation methods and short term sags ...


4

Some physics. Assuming the same material, length and loading, the bending strength is limited by the Second Moment of Inertia (I) of the cross sectional area. The math is complex, and even given a calculator, it's a bit confusing. Assuming a vertical loading, You can estimate the relative change in the I value by cubing the scale change. (This estimate ...


4

OK first let me say that if you're going to be making major structural changes to a building (and this counts as a pretty serious structural change in my mind) it would be well worth your while to get an engineer or other qualified building professional to help you with your design. If you just "wing it" you may be endangering the house and its occupants. ...



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