Thread: Steel pilie foundation Rust - How Bad is It

another rust.jpgGambel rust 1.jpgGambell foundation rust.jpg

I inspect homes in Alaska. Homes up here are built on raised foundations to keep the permafrost from melting, promote easy leveling, and for other good reasons. About ten Homes located in an extreme maritime environment are encountering problems with foundation rust. I don't have much experience with rust and would like some input.

Can I tell by looking at it how bad the problem is? What do I look for?
Some homes are worse than others. Could electrolysis or some other flaw be causing this?
Is there any way to tell how long do we have to take care of this?
Is there a quick easy way to slow it down?
What's the long term solution? (I've seen some, but most are very expensive)

There are probably questions I should have asked but didn't. I'd appreciate input from any knowledgeable professional.

Similar Threads:

• Steel I Beam Supported by 2x6's in foundation
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• Foundation Repair - exposed steel
• How Much Is Too Much Rust
• Foundation Steel?

Walter,

A marine environment is going to cause metal to rust. I know of no long-term fix. This is something that will require regular inspections and correction.

From the pictures that you provided, it looks to me like mostly surface corrosion, but that is not entirely clear from the photos. No way to tell what kind of damage has occurred to the bolts without removing the nuts (and even then, you would only be able to see the threads and maybe a little into the hole in the plate). The condition of the steel reinforcing in the concrete cannot be evaluated. Seems to me that there are coatings (Krylon has a primer that allegedly changes or binds with the rust) that can be used to protect the metal from further corrosion, but I don't have specific information about effectiveness or whether this is "snake oil". Also, how long any product will last is a question as well. Clearly, any significantly corroded metal should be replaced.

I know that Alaska is earthquake prone, but I don't know if that goes for the entire state (or if you get them where you are), but that would be a reasonable concern. If corrosion on the steel piers is common, there are likely contractors that specialize in remediation and corrective work.

Another option would be to check with a local structural engineer. He/she might have knowledge of a long-term preventative solution.

Is there a local home inspector association chapter (ASHI or similar) near you? I have found that my local chapter members are often a big help with local issues.

Gunnar:

I appreciate your reply. Earthquakes are not a problem in our region. In Anchorage, 900 miles away, they are an ever-pressing concern. There nearest ASHI, and the closest structural engineer are probably both in Anchorage. I appreciate the advice and am not going to dismiss either of these as a possibility but they're a bit of a distance away.

I took a look at the Krylon product. I also found a class of products called "rust converters." They might be a good choice. There is no road system up here. Everything ships by air. Non-hazardous materials are easier and less expensive to ship.

You are correct that the photos I provided show mostly surface rust. One of the photos, however, includes a layer of rust that appears to be peeling off like an onion peel; that might indicate a problem.

If I'm lucky somebody whose an expert on rust will stop by and give me a few pointers. Once again, thanks for your time.

Originally Posted by Walter Rose

I appreciate your reply. Earthquakes are not a problem in our region. In Anchorage, 900 miles away, they are an ever-pressing concern. There nearest ASHI, and the closest structural engineer are probably both in Anchorage. I appreciate the advice and am not going to dismiss either of these as a possibility but they're a bit of a distance away.

I took a look at the Krylon product. I also found a class of products called "rust converters." They might be a good choice. There is no road system up here. Everything ships by air. Non-hazardous materials are easier and less expensive to ship.

You are correct that the photos I provided show mostly surface rust. One of the photos, however, includes a layer of rust that appears to be peeling off like an onion peel; that might indicate a problem.

If I'm lucky somebody whose an expert on rust will stop by and give me a few pointers. Once again, thanks for your time.

Hi Walter,

Yes, I think I see what you are referring to. The flaking layers of rust in the third photo are likely a problem. Not a surface rust. Something like that might well need to be replaced, depending on how deep the corrosion is.

Coastal marine environment. Lots of salt spray will get pretty much everywhere. Pretty much any metal, other than bronze, is going to fail without regular repainting. I inspect homes at the CA coast on occasion and the electrical panels are often in poor condition, even when they are in a closet with a gasketed door. It's amazing how corrosive it is near the ocean.

Meter base corrosion / rust is another huge issue here. We started using stainless steel meter bases a couple of years back but are still having problems. Even though the box is stainless, the guts inside still corrode. Condensation inside the box, possibly combined with the incompatible metals is the culprit. We're still working on a solution to that one. Other problems with corrosion: Metal entry doors, porch lights, and window crank operator hardware (there's one steel part inside that rusts). I'm particularly concerned about rusting foundation pilings however; failure would be catastrophic.

Originally Posted by Walter Rose

Meter base corrosion / rust is another huge issue here. We started using stainless steel meter bases a couple of years back but are still having problems. Even though the box is stainless, the guts inside still corrode. Condensation inside the box, possibly combined with the incompatible metals is the culprit. We're still working on a solution to that one. Other problems with corrosion: Metal entry doors, porch lights, and window crank operator hardware (there's one steel part inside that rusts). I'm particularly concerned about rusting foundation pilings however; failure would be catastrophic.

Walter,

Although this is an interesting topic, it my not be the appropriate question if you are looking for input to report to your client. If you are looking for input for your report, I recommend you stick to your area of expertise and/or other areas that you are licensed to perform.

I believe the best response would be to report on your observations (facts) and advise that corrosion can weaken the structure and will continue to corrode over time creating a potential for structural failure. I recommend you advise the client to contact a licensed structural contractor or engineer for review and recommendations for repair as needed.

Ken,

The closest structural engineer is 900 miles away - he is trying to get information for his client instead of just dropping it in his client's lap while knowing that it is unlikely that a structural engineer can get to it for a reasonable cost.

What would you charge for an 1800 mile trip charge?

I inspect homes in the remote isolated Native Villages of Western Alaska for the Bering Straits Regional Housing Authority. I report my findings to the Housing Authority. I do not have clients. I will not profit from information I gather or things I learn on this forum.

The region I work in, population 10,000, is about the size of West Virginia. I inspect homes in 9 road isolated villages. They range in size from 120 to 650 people. Specialized expertise and licensed professionals are few and far between here. What I'm trying to do is learn more about rust. My goal is to accurately report on the scope and severity of the problem. If that is inappropriate for this forum please advise; I will go elsewhere.

- - - Updated - - -

I inspect homes in the remote isolated Native Villages of Western Alaska for the Bering Straits Regional Housing Authority. I report my findings to the Housing Authority. I do not have clients. I will not profit from information I gather or things I learn on this forum.

The region I work in, population 10,000, is about the size of West Virginia. I inspect homes in 9 road isolated villages. They range in size from 120 to 650 people. Specialized expertise and licensed professionals are few and far between here. What I'm trying to do is learn more about rust. My goal is to accurately report on the scope and severity of the problem. If that is inappropriate for this forum please advise; I will go elsewhere.

Walter,

When answers are provided, we all learn things we didn't know.

I don't envy your job and travel distances.

Observation: Suspect, atmospheric corrosion due to the proximity of salt in the atmosphere from the Bering Sea.
The metal oxidizes (corrodes) at the anode, forming rust or some other corrosion product.
Corrosion appears minimal. Appears to be, Uniform corrosion.
Recommend: Preventing corrosion involves stopping these reactions taking place.​​​​​ it is advisable to use a cleaning agent that has a pickling and/or passivating effect.

Originally Posted by ROBERT YOUNG

Observation: Suspect, atmospheric corrosion due to the proximity of salt in the atmosphere from the Bering Sea.
The metal oxidizes (corrodes) at the anode, forming rust or some other corrosion product.
Corrosion appears minimal. Appears to be, Uniform corrosion.
Recommend: Preventing corrosion involves stopping these reactions taking place.​​​​​ it is advisable to use a cleaning agent that has a pickling and/or passivating effect.

I know some report formats are quite stilted and stuffy in their presentation of the inspection results, such as those you posted.

I simply said it as people talked: The steel foundation supports were rusted, some with surface rust, others were rusted to the point of flaking and pitting - recommend blah, blah, blah (without all those high-flutin' words).

Maybe that was just me and my way of doing it.

Robert Young hit the nail on the head.

"Observation: Suspect, atmospheric corrosion due to the proximity of salt in the atmosphere from the Bering Sea. The metal oxidizes (corrodes) at the anode, forming rust or some other corrosion product. Corrosion appears minimal. Appears to be, Uniform corrosion. Recommend: Preventing corrosion involves stopping these reactions taking place.​​​​​ it is advisable to use a cleaning agent that has a pickling and/or passivating effect."

Thanks for the input folks..

Originally Posted by Walter Rose

Robert Young hit the nail on the head. .

Walter,

Only if you understand the terminology. "Pickling" and "passivating" are terms that I am not familiar with. My reports are more in line with Jerry's. I have found that most buyers prefer straightforward comments that do not involve "ten-cent words".

Also, from the thread and the third pic, the corrosion did not appear to be "minimal" or "uniform". Personally, I would stay away from terms that I do not fully understand and statements like "minimal". They can come back to bite an inspector, particularly when it turns out the corrosion is not minimal.

Perhaps an engineer can be consulted by phone with photos and verbal description? A phone consult will not get you any engineer's stamp, but would be much less expensive and might provide your client with enough information to proceed with. Contacting the manufacturers of these "rust converters" should also provide your client with information as to whether or not their product would be effective in this case.

Originally Posted by Gunnar Alquist

Walter,

Only if you understand the terminology. "Pickling" and "passivating" are terms that I am not familiar with. My reports are more in line with Jerry's. I have found that most buyers prefer straightforward comments that do not involve "ten-cent words".

Recommend: Preventing corrosion involves stopping these reactions taking place.

The "Pickling" and "passivating" are terms much, if not the majority, of works know well in remote settings. By Pickling yourself, with your choice or pickling agent, mine was 10 year old single malt scotch, and beer, you pacify/passivating your frustration preventing negative knee jerk reactions from taking place.
IE: Like running outside and sealing the steel with tremclad.
Its an old northern expression like, concession road, day liner, eh, Kokanee, pickerel.
I feel everyone should “Take off to the Great White North" at least once in your lifetime.
Bob & Doug.JPG

Robert,

Some have been in that great white north and found it to not be as great as the sunny south.

Since Walter is inspecting for a government agency, he can do well using technical terms and engineering jargon to fill the pages of his reports. "Structural steel foundation member surfaces were found to be in an advanced state of corrosive degradation etc"

In a marine environment, I suggest doing what the mariners do, chip off the scale and apply paint.

We took a trip recently on the Black Ball ferry from Victoria to Port Angeles. That ship built in 1959, was getting new paint where the window trim was rusting. Same with our BC ferries here, painting goes on whenever the weather permits it.


http://maritimematters.com/2009/12/m...-shawn-j-dake/

Moring John.

The idea of describing the various ways corrosion can damage metals by it appearance had be used by many before Fontana and Greene coauthored their famous book in 1967.

There are 8 types of corrosion in steel.
1: Uniform Attack, to which I think are exhibited in the permafrost bearing pad and steel girders.
Uniform attack is the most common form of corrosion. It is normally characterized by a chemical or electrochemical reaction which proceeds uniformly over the entire exposed surface or over a large area. The metal becomes thinner and eventually fails. For example, a piece of steel or zinc immersed in dilute sulfuric acid will normally dissolve at a uniform rate over its entire surface. A sheet iron roof will show essentially the same degree of rusting over its entire outside surface.

2: Galvanic or Two-Metal Corrosion.
In this case, The corrosion would be exhibited at the connections and fasteners.

3: Crevice Corrosion.
Frequently occurs within crevices and other shielded areas.

4: Pitting.
Extremely localized attack that results in holes in the metal.

5: Intergranular Corrosion.
Localized attack at and adjacent to grain boundaries.

6: Selective leaching.
(dezincification)

7: Erosion Corrosion.
acceleration or increase in rate of deterioration or attack on a metal because of relative movement between a corrosive fluid and the metal surface.

8: Stress-corrosion cracking.
Cracking caused by the simultaneous presence of tensile stress.

http://corrosion-doctors.org/Corrosi...tory/Eight.htm

Walter, I have seen ads on TV for a product called Rustoleum. I haven't tried it myself, but their claim is that it removes rust and won't allow future rusting. You should be able to buy it at Home Depot or Walmart.

Originally Posted by ROBERT YOUNG

Morning John.

The idea of describing various ways corrosion damages metals had been used by many before. One such article by Fontana and Greene coauthored in 1967.

There are 8 types of corrosion in steel.
1: Uniform Attack, to which I think are exhibited in the permafrost bearing pad and steel girders.
Uniform attack is the most common form of corrosion. It is normally characterized by a chemical or electrochemical reaction which proceeds uniformly over the entire exposed surface or over a large area. The metal becomes thinner and eventually fails. For example, a piece of steel or zinc immersed in dilute sulfuric acid will normally dissolve at a uniform rate over its entire surface. A sheet iron roof will show essentially the same degree of rusting over its entire outside surface.

2: Galvanic or Two-Metal Corrosion.
In this case, The corrosion would be exhibited at the connections and fasteners.

3: Crevice Corrosion.
Frequently occurs within crevices and other shielded areas.

4: Pitting.
Extremely localized attack that results in holes in the metal.

5: Intergranular Corrosion.
Localized attack at and adjacent to grain boundaries.

6: Selective leaching.
(dezincification)

7: Erosion Corrosion.
acceleration or increase in rate of deterioration or attack on a metal because of relative movement between a corrosive fluid and the metal surface.

8: Stress-corrosion cracking.
Cracking caused by the simultaneous presence of tensile stress.

Eight forms of corrosion

Typos. Sorry.

Originally Posted by Walter Rose

......

Can I tell by looking at it how bad the problem is? What do I look for?
Some homes are worse than others. Could electrolysis or some other flaw be causing this?
Is there any way to tell how long do we have to take care of this?
Is there a quick easy way to slow it down?
What's the long term solution? (I've seen some, but most are very expensive)....

Walter, Interesting job by virtue of location.

1) How bad is it? Depends on metal thickness and degree of deterioration. If metal was oversized by 10% and you have 5% loss then you still exceed the sizing by 5% depending on uniformity of loss due to deterioration.
----What do I look for? All metals oxidize even stainless steel. It will depend on the metal.
----Way to tell how long do we have to take care of this? Depend on rate of deterioration and minimal structural requirements. Purely an engendering thing that manufacture can help with.

2) Electrolysis or other flaw the cause?
Here is a good article for a general explanation: Corrosion

--Unless there is an electrical current present or being created, it is not electrolysis.
--There is Galvanic Corrosion between dissimilar metals which has become a big issue since to introduction of Cu (copper) into treated lumber.

3) Quick easy way to slow it down? Internet research " rust neutralization or rust converter" as search criteria. There are materials that can be applied that react and seal existing rust
/oxidation. Some are easy others not so easy. I don't have specific recommendations. especially since you need to know chemical composition for transportation in your area.
You will get these types of results:
BlackStar Rust Converter

Rust Converter: 1-Step Rust Killer

4) What's the long term solution? I know everything is more expensive in Alaska due to transportation costs, kinda like the Caribbean. Like most things it is a mater of trade off between labor and the materials to get the best job for the cost.

I would think that actually replacing the supports would be the least expensive long term method. They appear to be bolted together. Jacking to release pressure then replacement. Coating the materials would yield a longer life to the project which could be done prior to shipping to site.

Originally Posted by Garry Sorrells

Walter, Interesting job by virtue of location.


4) What's the long term solution? I know everything is more expensive in Alaska due to transportation costs, kinda like the Caribbean. Like most things it is a mater of trade off between labor and the materials to get the best job for the cost.

I would think that actually replacing the supports would be the least expensive long term method. They appear to be bolted together. Jacking to release pressure then replacement. Coating the materials would yield a longer life to the project which could be done prior to shipping to site.

Another consideration would be replacing with high-grade stainless steel for longevity - all depends on 'how old are they' 'how much to replace with steel' 'how much to replace with high grade SS' cost between the two replacement options would be considered against longevity, which (for steel) is a known based on the current age and condition, with SS being much longer (nothing 'lasts forever', some come close enough over the long term to consider it that).

Steel or SS - labor to remove and install new is the same
Steel or SS - shipping is the same (or very close to the same)
Steel or SS - material cost is more for SS
Steel or SS - fabrication cost is somewhat more for SS

Originally Posted by Jerry Peck

Another consideration would be replacing with high-grade stainless steel for longevity - all depends on 'how old are they' 'how much to replace with steel' 'how much to replace with high grade SS' cost between the two replacement options would be considered against longevity, which (for steel) is a known based on the current age and condition, with SS being much longer (nothing 'lasts forever', some come close enough over the long term to consider it that).

Steel or SS - labor to remove and install new is the same
Steel or SS - shipping is the same (or very close to the same)
Steel or SS - material cost is more for SS
Steel or SS - fabrication cost is somewhat more for SS

I'm curious about use of stainless in this case. My understanding is that stainless does not rust because the chromium combines with the oxygen at the surface to make a very thin layer of chromium oxide which protects the iron from oxidizing. However, I have seen stainless steel hardware on sailboats (marine environment) that look fine on the surface, but were corroded-out on the back side where they were attached to the hull. This is apparently due to the limited amount of oxygen (there is usually a sealant or gasket used where the hardware is attached to the hull).

So, (finally) my question:

Would stainless steel rust where it was embedded in the concrete or placed against something that limited airflow? Even if the steel piles do not corrode (or corrode quickly), the anchors that are embedded in the concrete might still be subject to corrosion.

Originally Posted by Gunnar Alquist

So, (finally) my question:

Would stainless steel rust where it was embedded in the concrete or placed against something that limited airflow? Even if the steel piles do not corrode (or corrode quickly), the anchors that are embedded in the concrete might still be subject to corrosion.

The only answer I can give is that stainless steel reinforcing bars are used in concrete columns and slabs along the ocean in South Florida . specified for the worst locations to avoid rusting and spalling of the concrete due to that rusting.

Where those fitting you saw on boats stainless steel through and through, or chrome plated on the outside?

I know that the supposed 'maximum cost efficient' SS is 18% chromium, less chromium and it rusts/corrodes faster with each % reduction of chromium, and more chromium begins to not make much difference relative to the higher chromium % - i.e. 20% chromium is negligibly more resistant than 18% but cost substantially more, and 24% chromium is negligibly more resistant than 20% but costs substantially more. But if you really want resistance to corrosion and have tons of money, I guess there is a limit to the % chromium which adversely affects the steel in other ways. Note: I an "not" a metallurgist (I even had to look it up to spell it).

Originally Posted by Jerry Peck

Where those fitting you saw on boats stainless steel through and through, or chrome plated on the outside?

Hi Jerry,

Yes, stainless steel "chain plates". The mast cable stays are anchored to the chain plates just above the deck. The chain plates then penetrate through the deck and are anchored to the hull. The degradation was found between the metal and the hull of the boat (inside the cabin). I have looked for my photos, but I am unable to find any. If you search "corroded chain plates" you can see similar.

Originally Posted by Jerry Peck

I know that the supposed 'maximum cost efficient' SS is 18% chromium, less chromium and it rusts/corrodes faster with each % reduction of chromium, and more chromium begins to not make much difference relative to the higher chromium % - i.e. 20% chromium is negligibly more resistant than 18% but cost substantially more, and 24% chromium is negligibly more resistant than 20% but costs substantially more. But if you really want resistance to corrosion and have tons of money, I guess there is a limit to the % chromium which adversely affects the steel in other ways. Note: I an "not" a metallurgist (I even had to look it up to spell it).

It might have been the percentage of chromium, as you suggest. I believe I read that a minimum of 12% is necessary to prevent corrosion. I do not know how to tell the chromium content. Also, I think higher chromium makes for more brittle metal.

Originally Posted by Gunnar Alquist

It might have been the percentage of chromium, as you suggest. I believe I read that a minimum of 12% is necessary to prevent corrosion. I do not know how to tell the chromium content. Also, I think higher chromium makes for more brittle metal.

For more than I knew, or will remember, about stainless steel types and their uses:
- Stainless Steel Information Knowledge | 18-8 | 304 | 316
- https://9to5mac.files.wordpress.com/...tion-chart.pdf
- http://www.aksteel.com/pdf/markets_p...comparator.pdf
- Stainless Steel Grades - Stainless Steel (SS) Material Properties | Stainless Sales

(No, don't bother to ask what I remember from what I read in those - I'll answer 'Huh? What articles?'

Holy smokes. Even dumbed-down for me, it was a bit much.

New member here, just catching up on this thread. Walter, I definitely agree with Jerry though, I don't envy your travel. I travel usually 30-45 minutes only and I find myself complaining (though silently) I forget when I had to travel 2.5 hours each way for my corporate job each day. Definitely glad for this profession, even though it has it's slow spells it's enjoyable when it's good.

Charles G.
www.longislandhomeinspectionpros.com

To determine how significant corrosion is try to determine how much the cross section has been reduced.

Regarding slowing the corrosion, a zinc rich primer is recommended. Good zinc rich primers are expensive and not readily available.