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68 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 ...
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48 votes
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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. ...
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31 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 ...
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  • 95.7k
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 ...
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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-...
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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 ...
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  • 22.5k
24 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 ...
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  • 349
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 ...
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  • 20.4k
18 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 ...
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  • 527
17 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 ...
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  • 128k
15 votes
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Is notching a flange on an I-Joist ever acceptable?

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' ...
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  • 19.3k
15 votes
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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.
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  • 53.3k
14 votes

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

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 ...
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  • 9,779
13 votes
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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 ...
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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 ...
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  • 331
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 ...
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  • 6,906
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 ...
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11 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. ...
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  • 5,498
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 ...
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  • 95.7k
9 votes
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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 ...
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  • 104k
9 votes

Contractor cut joist hangers to make them fit

You never cut hangers unless they are made for cutting. Call in a inspector who will advise you or the engineer who done the design but don't under any circumstances let this go without it being ...
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9 votes

Can I overlay lumber perpendicular to floor joists to raise the floor height?

I would say that the main issue with putting down boards like that is cupping or bowing of the wood especially since this is a high moisture area; that's dirt beneath the joists, right? Look at any ...
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9 votes
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Should I repair or replace floor joists with holes in poor locations?

None of the holes are an issue. There is some slight compression with the one joist - in your top picture. But it doesn't look to be an issue and it is certainly not caused by that small hole. If ...
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  • 46.2k
8 votes
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Hurricane ties installed using joist hanger nails top AND bottom. Should I yank them out?

Nah - most of the strength is in shear, and joist hanger nails are nice and fat so they have good shear strength. also, yanking them is likely to be harder than you think. The actual nailing ...
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  • 133k
8 votes

Do I need a nailing edge around the perimeter of my room for my new AdvanTech subfloor?

I did it both ways in a laundry/powder room I completed last year. Along the one wall, I installed the nailing plates your described. Along another wall, I didn't, in part because the sole plate for ...
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  • 3,959
8 votes
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Do I need a nailing edge around the perimeter of my room for my new AdvanTech subfloor?

If I don't install a nailing edge, is it likely I will have a noticeable bounce? No, because you can't stand that close to the wall. The only unsupported edge is right at the face of the wall If ...
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  • 5,551
8 votes

Are my trusses capable of carrying the load of insulation and drywall?

Yes, your trusses will support insulation and gypsum board. The Building Code requires the bottom chord of trusses and ceiling joists to support a minimum of 10 lbs. per square foot. (See IRC Table ...
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  • 22.5k
8 votes

How to reinforce a joist with plumbing running through it?

Also not an engineer but building my own home. I would suggest one of four solutions, in no special order, but please check with a structural engineer if you have any doubts. I would draw attention to ...
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  • 610
8 votes

How to reinforce a joist with plumbing running through it?

I have dealt with this in older houses that have had water damage in a location in a bathroom. Basically you will need two things with maybe a third: You need metal sleeves around each of these. ...
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  • 46.2k
8 votes
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What are the actual dimensions of a 4x8' subfloor plywood panel

Looking for "sanded" plywood and check the specification for the panel you are looking to purchase. This one is a 4x8x3/4 from Menards. https://www.menards.com/main/building-materials/panel-...
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