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View Full Version : Unusual Repairs to Joists



Nick Ostrowski
11-30-2012, 03:13 PM
I saw these repairs at an inspection today. Pocket rot (ie - rot on the joist ends at the bearing point in the foundation walls) is pretty common around here, especially in older homes in Philadelphia. Over 50% of the joist ends on the left-hand side of the basement had been repaired. The repairs consisted of a steel angle shelf inserted into the foundation wall beneath the joists and extending less than 2 feet past the bearing point. The angle shelfs were not the same width as the joists and the depth in which they were inserted into the foundation wall is unknown. I found 3-4 joists with pocket rot on joists that had these repairs.

I told the buyers I have never seen repairs like this and have no way of knowing whether or not they are structurally adequate. I recommended they have these repairs evaluated because I have no way of knowing if they are sufficient. I lean towards saying "not adequate" but I've never seen joists repaired in this manner.

Has anybody seen repairs made like this?

Jack Feldmann
11-30-2012, 05:48 PM
While I am not an engineer, I would guess that they are nowhere near strong enough to do much good at all.
Angle is likely not large enough and does not have enough fasteners.

Lon Henderson
11-30-2012, 06:15 PM
I vote inadequate, although done differently with angle iron that was longer, went higher up the side of the joists and more attachment lags, and it might be adequate. I agree with your call for a structural engineer. I haven't seen anyone do that either.

Markus Keller
11-30-2012, 06:37 PM
I've done joist end repairs like that in the past. We've used actual steel angle irons or steel U channels. However that looks like the standard aluminum stock stuff you can buy at big box stores. Also definitely looks too short. I also have to write it up as inadequate.

Chris McIntyre
12-02-2012, 06:24 PM
However that looks like the standard aluminum stock stuff you can buy at big box stores. Also definitely looks too short.

I agree. Looks like they were trying to cover up the damage instead of repairing it.

Thom Huggett
12-03-2012, 09:37 AM
Definitely inadequate structurally as shown in the pictures, plus it does not correct the issue of non-treated wood in contact with concrete addressed in International Residential Code Section R317. Those joists should be supported on a preservative treated ledger bolted to the foundation wall.

Mark Reinmiller
03-20-2014, 07:09 PM
I saw these repairs at an inspection today. Pocket rot (ie - rot on the joist ends at the bearing point in the foundation walls) is pretty common around here, especially in older homes in Philadelphia. Over 50% of the joist ends on the left-hand side of the basement had been repaired. The repairs consisted of a steel angle shelf inserted into the foundation wall beneath the joists and extending less than 2 feet past the bearing point. The angle shelfs were not the same width as the joists and the depth in which they were inserted into the foundation wall is unknown. I found 3-4 joists with pocket rot on joists that had these repairs.

I told the buyers I have never seen repairs like this and have no way of knowing whether or not they are structurally adequate. I recommended they have these repairs evaluated because I have no way of knowing if they are sufficient. I lean towards saying "not adequate" but I've never seen joists repaired in this manner.

Has anybody seen repairs made like this?

A bit late in responding, but its still a relevant topic. That is an old method of repair and it is not a bad one. I would use about a 2"x2"x3/16" steel angle minimum and would use epoxy paint, galvanized, or some other good method to protect the steel from corrosion. This repair works well when the joist is deteriorated right at the wall to maybe an inch or so out from the wall. anything more than that and I would up the size of the angle. The length does not have to be very long. One 3/8" lag bolt can do the job if it is about a foot out from the wall. The lag bolt should actually be installed in the bottom of the joist so it is loaded in withdraw. It does not seem like it makes sense, but think about it like a lever arm. I have used the method a few times and have run the calculations. It works and the fact that many of these repairs still look fine after maybe 50 years backs that up.

Raymond Wand
03-21-2014, 04:56 AM
Start with repairing/improving the conditions which caused it and allow the rot to continue. Such as grading, damp basement, rising damp. Joists may also be subject to crushing.

Mark Reinmiller
03-21-2014, 03:11 PM
Start with repairing/improving the conditions which caused it and allow the rot to continue. Such as grading, damp basement, rising damp. Joists may also be subject to crushing.

Raymond, But the time I see these they are usually completely deteriorated at the bearing ends. Many are below grade and there is little potential to improve grading.

Many times the ends are also crushed. Even with improvements there is still a need for repairs.

Jerry Peck
03-21-2014, 04:12 PM
Definitely inadequate structurally as shown in the pictures, plus it does not correct the issue of non-treated wood in contact with concrete addressed in International Residential Code Section R317. Those joists should be supported on a preservative treated ledger bolted to the foundation wall.

(Presuming, I am sure, that the foundation wall has a filled lintel/bond beam around the top of it and is not just hollow blocks for the top course.)

I'd be inclined to go with this information for what is needed.

Nick Ostrowski
03-21-2014, 07:22 PM
This was a stacked stone foundation with the bearing ends of the joists very close to the exterior grade level. The pocket rot is a very common defect around here due to the way many of these older houses were built. Unfortunately there is often little to nothing that can be done to improve exterior grading and drainage easily as most of the exterior ground around these Philadelphia houses is concrete patio and walkways.