69 votes

Is it safe to remove the bottom chords of a series of garage roof trusses?

Absolutely not safe. Those trusses were engineered with a heavy (critical) dependency on the bottom chords, which are in tension. Removal has left them extremely vulnerable to collapse due to ...
isherwood's user avatar
  • 137k
49 votes
Accepted

I want to build an all metal, self-designed building. Are metal frame and joists really that infeasible?

You're probably thinking of the wrong sort of metal When most people think of "metal buildings", they think of I-beams, columns, and open-web joists, as found in large-scale construction. ...
ThreePhaseEel's user avatar
32 votes

Is it safe to remove the bottom chords of a series of garage roof trusses?

With no bracing above, you might want to check the out side walls - they are probably already spreading. Once they start moving the stabilization and repair can cost many thousands if the roof stays ...
Ed Beal's user avatar
  • 103k
29 votes

How to reinforce a joist with plumbing running through it?

I had an electrician notch the top 5" of a 2x10 (9" old growth Douglas fir) in the middle of an 18' span. I brought in a structural engineer and he said the 18' 2x10 was already over current ...
Fresh Codemonger's user avatar
28 votes

I want to build an all metal, self-designed building. Are metal frame and joists really that infeasible?

There are loads of pre-designed steel building shells out there. Use one. These are offered by commercial building companies for farm and industrial buildings. They have gotten a family of designs pre-...
Harper - Reinstate Monica's user avatar
26 votes

Can I hang a swing from manufactured "I" joists made of wood?

The answer with I-joists is always "ask the manufacturer." Your image's "Trus Joist TJI 210" is sufficient to figure out the manufacturer, Weyerhaeuser. Since there appears to be ...
popham's user avatar
  • 10.4k
25 votes

Contractor cut joist hangers to make them fit

No, it’s not acceptable to cut the joist hangers. In order to determine if they are acceptable anyway, there are several issues to review: 1) hangers are notched, 2) incomplete nailing, 3) wrong ...
Lee Sam's user avatar
  • 23.2k
25 votes

How to reinforce a joist with plumbing running through it?

I would sister 2 pieces 3/4" marine grade Plywood Braces (since it's under a toilet) on one side of the damaged joist as shown below. Use Epoxy or Urthane glue and SS deck screws to tie them to ...
BobM's user avatar
  • 359
22 votes

Long crack in I joist flange

That looks like typical checking just from the wood aging and drying out. It's down the long axis of the beam vs. across the beam which would indicate a problem. Also that portion of the beam is ...
jwh20's user avatar
  • 23.3k
20 votes

Is notching a flange on an I-Joist ever acceptable?

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 ...
Tester101's user avatar
  • 132k
19 votes

Is it safe to remove the bottom chords of a series of garage roof trusses?

The triangle is an extremely stable form of architecture precisely because it has three sides. You remove one side, and you have one of the least stable forms of architecture on account that two ...
J D's user avatar
  • 682
19 votes

What's the purpose of this lumber resting on top plate of the wall?

That's standard practice to create backing for drywall (or plaster lath) where walls are parallel with ceiling framing members. It's reasonable that the carpenter would've used extra subfloor material ...
isherwood's user avatar
  • 137k
17 votes
Accepted

Is notching a flange on an I-Joist ever acceptable?

Point your home builder to page 9 of Weyerhauser's I-joist document. See the bottom right of the page where it says "DO NOT cut or notch flange". It is typical of all I-joist manufacturers' ...
ArchonOSX's user avatar
  • 19.8k
17 votes

Removing Load-Bearing Wall in Timber-Framed House

What you're proposing and/or actively doing is a major structural change to the building. As such, you need to be sure that it's both safe and building code compliant. There is no way any random ...
jwh20's user avatar
  • 23.3k
15 votes

Is notching a flange on an I-Joist ever acceptable?

The Is 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 ...
Iggy's user avatar
  • 10.3k
15 votes
Accepted

What is this orange yellow substance on my wooden studs inside walls?

You are looking at tree sap. It's harmless. It's dried out so if it's gonna cause you to lose sleep at night, just scrape it off with a chisel.
JACK's user avatar
  • 80.5k
14 votes
Accepted

Repairing a notched floor joist

Good on you for leveling up your knowledge and learning where not to drill or saw on joists. On that same note, here's an excellent summary from BuildingAdvisor titled Guide to Notching and Boring ...
Matt Simerson's user avatar
14 votes
Accepted

How should I deal with this protrusion in future drywall ceiling?

Jack it into place and nail it (spike it) in while jacked into place. Don't overdo and jack up the whole laminated beam - just jack up the loose bit, and use suitable spikes into holes somewhat ...
Ecnerwal's user avatar
  • 214k
14 votes

Any idea what this structure in my attic might be?

My guess is a former light well. It looks like we are seeing the BACK of the drywall there, which would corroborate this a little. If you poke a hole and see the drywall has been painted white on the ...
jay613's user avatar
  • 37.4k
14 votes
Accepted

How can I support a sagging double joist where the hanger was cut?

Move the water line. I realize that you don't want to, but you have to--if only a little. A small offset of a couple inches will allow you to fix the framing problem. Start with an elbow just below ...
isherwood's user avatar
  • 137k
13 votes

I want to build an all metal, self-designed building. Are metal frame and joists really that infeasible?

Background: My father was a structural engineer in the steel building industry and did exactly what you are asking for - calculate the statics of buildings and other large constructions, dimension ...
AnoE's user avatar
  • 330
13 votes

How can I temporarily support a ceiling with embedded heat tubing?

It's just not necessary to support the framing from above. Temporary walls are put up under drywall all the time, and the gypsum doesn't crush. Actual plaster certainly won't. Just use a 2x6 or wider ...
isherwood's user avatar
  • 137k
12 votes

Is it safe to remove the bottom chords of a series of garage roof trusses?

As pictured - very bad idea. It may work IF the roof is re-engineered to carry a lot more of the stress across the top and bottom of the cutout. That means a much beefier horizontal beam on all ...
Criggie's user avatar
  • 10.6k
12 votes

Contractor cut joist hangers to make them fit

Cutting a hanger is never a good idea and should never be accepted. It's shoddy workmanship by the contractor and there were numerous solutions that could have avoided this (starting with properly ...
indianajonesy's user avatar
12 votes

How do I screw through a metal bathroom fan box to affix it to the joist?

Almost any wood screw. It takes only say 3/4" of penetration into a joist to secure such a housing. Thread type doesn't much matter. Diameter doesn't, either, though thinner screws will go in ...
isherwood's user avatar
  • 137k
10 votes

How urgently should this joist be looked at by a pro?

I would get a General contractor, if you can’t drive a couple of nails or screws. As far as urgent , probably not at all urgent. I would want some joists hangers on the ones hanging down and only toe ...
Ed Beal's user avatar
  • 103k
10 votes

I want to build an all metal, self-designed building. Are metal frame and joists really that infeasible?

Prefab metal shed. These are popular and durable. They are used on farms and workyards everywhere. Many, many sizes and shapes are available. Quonset huts many decades old are still in service. ...
Willk's user avatar
  • 6,593
10 votes

Floor Joists Knot

It always happens and was a total miss by the framing crew. But, unless you're springy upstairs it's not really a problem. The adjacent joists will assist just fine for normal empty area loads above. ...
Iggy's user avatar
  • 10.3k
10 votes
Accepted

Joist are not properly attached to the band joist - found by home inspector. What does the repair entail?

Your rim board's purpose is to prevent the floor joist end from rotating. Imagine standing a couple of 2x12s on a flat surface with a sheet of plywood on top. Standing on this plywood the platform ...
popham's user avatar
  • 10.4k
9 votes
Accepted

Increase size of ceiling joist compromise roof strength?

You don't have joists or rafters. You have engineered roof trusses. The bottom chords are 2x4 because that's all that's required for your scenario. They don't span the ceiling themselves. They're part ...
isherwood's user avatar
  • 137k

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