Critical Plumbing Issues: Understanding Floor Joist Safety

TLDR
The video showed floor joists with deep cuts and pieces that did not seem to rest on a support. The work looked wrong, but I could not name the exact fault or repair from a video.

Table of Contents

What I Could See

Someone sent me videos from a bath where a plumber, or another worker on the pipes, seemed to have cut deep into several floor joists. In one spot, almost none of the old board remained. Another piece looked newer, as if someone had added wood beside the damaged area.

That was enough to say the work looked bad. I said I was no Boy Scout about code, and this still looked clearly wrong. It was not enough to say who did it, why the new wood was there, or how the floor should be fixed.

Why the Cuts Concerned Me

Rules limit where and how much a joist can be cut or bored. The limit depends on the member, the cut, and its location along the span. During the recording, I guessed that a limit might be near 30% in some cases and immediately said to look up the real rule. Do not use that guess as a cut allowance. For example, the 2021 IRC separates its limits for solid lumber from engineered wood products. The adopted local code, product instructions, existing damage, and actual design control this house.

The cuts looked far beyond a normal hole. Some pieces seemed to be held only by nearby wood and nails. The cut joist itself did not seem to bear at both ends.

Do Not Diagnose This From an Article
A photo or short video cannot prove the loads, spans, wood type, joints, or needed repair. The recording was a reaction to clear damage, not an engineer’s review.

Why the House Could Still Look Fine

Houses can remain standing even when part of the structure is wrong. That resilience can hide a serious problem for a while. In the video, I warned that the visibly damaged condition could eventually fail, even though the house had not already collapsed.

That observation should not be turned into a countdown, a load percentage, or a specific failure scenario. None of those details were established in the source.

The Honest Next Step

Record what you can see. Have the real floor checked by a qualified structural professional and the permit authority for that job. The source does not give one sistering plan, a repair price, or a claim that an engineer’s letter shifts all risk.

FAQ

Did the video prove a plumber caused the damage?

No. I suspected the plumbing work was involved because of where the cuts appeared, but I did not establish who made them.

Did the newer wood prove somebody tried to hide the problem?

No. It showed that newer material may have been added. The video did not establish why it was added or whether it was a valid repair.

What repair did the source recommend?

It did not provide a repair design. The central point was that the cuts looked clearly wrong and the exact code and structural requirements needed to be checked.