Stainless Steel Rebar?

[etd66ss]

Has anyone used stainless rebar to pin the logs in their LHBA style home?

I'm probably not in the best of climates for a log home to begin with, and I have a concern about using mild steel rebar embedded in logs (hopefully when I go to source the rebar I can make sure it is not Chinese junk). Cast in concrete is one thing, in logs, I'm not so sure I like the mild steel rebar. I know if the overhangs are large and the chinking can breathe, theoretically the initial layer of rust will prevent further oxidation of the rebar yadda yadda. However, if it is just a matter of cost, I think I would personally go with stainless rebar, as well as stainless nails for the chinking.

Just wondering if anyone else has had such thoughts on the matter.

btw, yes, I am taking the class. I'm not all in on BnP method as of yet, but I will take the class and gain as much knowledge as I can.

[rckclmbr428]

Sure it can be done, but I would reckon it might be a lot cheaper to buy coated rebar instead

[etd66ss]

Well, from some quick research there are a few choices.

Mild steel - black oxide coating - non-corrosion resistant
Mild steel - epoxy coating - (1.4x the cost of black oxide)- 150-1100 times more corrosion resistant to black oxide (the range is based on damaged to undamaged and coated ends) - bending damages corrosion resistance
Mild steel - galvanized coating - (1.5x the cost of black oxide) - 38 times more corrosion resistant to black oxide - bending weakens coating
Mild steel - stainless clad - (1.9x the cost of black oxide) - 800-1500 times more corrosion resistant to black oxide (only if cut ends are coated)
Solid SS - (5.8x the coast of black oxide) - 800-1500 times more corrosion resistant to black oxide, damage to rebar is irrelevant in terms of corrosion resistance

If I calculate out 24" lengths of #4 rebar to build a 34 x 34 BnP home 12 courses high, and the pins are on ave (3 ft ?) apart and I use $0.50/lb for the black oxide rebar, I come up with ~$360 for black oxide and $2070 for solid stainless rebar.

I think I'd actually opt for the solid stainless.

I guess one question is, does the rust actually help the grip strength when the log shrinks on the rebar, and would something like an epoxy coating have an adverse effect.

[rocklock]

good grief... I have posted these pictures before. A little rust will not make any difference. I cut out some windows from my small shed... hence the small wood... These were unprotected for at least three years before I split them for fire wood... The log is Doug Fir...

About your math... probably times 6 or 7 would be a better estimate..

http://i154.photobucket.com/albums/s274/flintlock1/miss%20stuff/IMG_2614.jpg The wood

[etd66ss]

It would be cool to have a picture like that from a 150 year old BnP home in a wet climate.


About your math... probably times 6 or 7 would be a better estimate..


You mean from the black oxide rebar to solid stainless? I calculated ~1000 ft of rebar total, not sure if you meant that...

[tetonpeak]

Just an opinion but if there is enough moisture getting to the rebar to be concerned about failure due to corrosion I would assume it is far too much moisture getting to the wood. Properly constructed the rebar will be sealed from moisture for the life of the home. Surface rust would not be an issue. Anyway I don't think it would be a concern to use standard mild steel rebar, just my thoughts.

[Plumb Level]

What climate is this by the way?

I think Tetonpeak nailed it.....or rebared it.

[etd66ss]

What climate is this by the way?

I think Tetonpeak nailed it.....or rebared it.

Western New York climate, rust belt, lake effect snow, very damp in spring/early summer for 3-4 months, etc. My house will be built in the great lakes plain region close to lake Ontario.

I can see the point about if the rebar is getting further oxidation, it means it is getting both moisture and oxygen, meaning the logs are getting wet/damp. Even still, looking at a lot of bridge abutments here, the concrete columns with embedded rebar crack apart a lot due to the rebar expanding from rust, seems to happen to many columns in 3-4 decades.

It is probably correct that normal black oxide rebar would work fine, but if it is only going to cost me and extra ~$1800 to go with solid stainless at time of construction, seems like a no brainer to me. I was just wondering if any LHBA members have used stainless in their builds, I'm not sure I see a downside other than cost and/or it being labeled overkill. I'm already going against the grain building a BnP style home in the first place, I don't mind going against the grain within the LHBA community as well :)

[allen84]

I don't think stainless would be worth the extra expense. And I think the only reason your vehicles rust so bad is from snow and road salt.... A few years ago I bought a rust free truck that came from New York. It spent it's entire life in a cemetery. Great low mileage truck, if you could get past the dead body smell (joking). It did look like the driver door had been opened into every headstone in the graveyard tho... Union workers.

[rocklock]

If I calculate out 24" lengths of #4 rebar to build a 34 x 34 BnP home 12 courses high, and the pins are on ave (3 ft ?) apart and I use $0.50/lb for the black oxide rebar, I come up with ~$360 for black oxide and $2070 for solid stainless rebar.

I have stated that I have 900 pieces of rebar in my log home... 23 inches long... or about 1800 feet. Probably 2000 for a 34 by 34. I don't know the price per pound but the last time I looked at the delivered price it was about $6.50 for a 20 foot stick... or 100 sticks... or total cost of $650 for 100 sticks.

This is about 100% more than your estimate...

good luck

[NWscott]

. . . total cost of $650 for 100 sticks.

So, asking price of $200 for 91 sticks of 20 ft. would be considered a deal?

I'm aware there is a "Post your CL finds" thread, but unlike LHN, I am keeping on topic here ;)

http://seattle.craigslist.org/tac/mat/5494544501.html

Craigslist to the rescue!

I'm still in the dreaming and planning stage Rocklock, after just taking the class in Feb (20-21). Anybody else in the Puget Sound looking for a good deal?

Etd66ss, at the end of the day...it's your pocketbook that is paying for it, and your peace of mind once they're in. Every home is going to be unique, so go with your dreams. (consider the helpful advice of those who've done it already too, or it may be a nightmare)

[taylorjones]

I am very attracted to the LHBA style, as they focus on element protection via overhangs and pier systems for airflow. But the main thing that keeps bothering me is the "sweating" that occurs with metal. I understand that the water penetration will be about nil, but I wonder about humidity.

I pulled off steel panels on a standing seam roof only 9 months old and there was moisture trapped between the steel and the synthetic underlayment from the rain occurring during installation. Granted, that is between a water tight and vapor tight barrier. Still, water can linger. I am still convinced this style of construction will outlast near all alternatives, but I am curious how the steel would fare after 500+ years.

[loghousenut]

I am very attracted to the LHBA style, as they focus on element protection via overhangs and pier systems for airflow. But the main thing that keeps bothering me is the "sweating" that occurs with metal. I understand that the water penetration will be about nil, but I wonder about humidity.

I pulled off steel panels on a standing seam roof only 9 months old and there was moisture trapped between the steel and the synthetic underlayment from the rain occurring during installation. Granted, that is between a water tight and vapor tight barrier. Still, water can linger. I am still convinced this style of construction will outlast near all alternatives, but I am curious how the steel would fare after 500+ years.

I worry about that sweating issue on the panels also. We put a 2" ventilated air gap under all of our steel roof that is over the living space. As for sweating of the rebar, I think it is a non-issue. That part of the system works a lot better than any of us mortal's work. It is just a log house and only has to last 4 or 5 generations to suit my wife. I'll get back to you when we know how my place does in the long term.

[taylorjones]

I worry about that sweating issue on the panels also. We put a 2" ventilated air gap under all of our steel roof that is over the living space. As for sweating of the rebar, I think it is a non-issue. That part of the system works a lot better than any of us mortal's work. It is just a log house and only has to last 4 or 5 generations to suit my wife. I'll get back to you when we know how my place does in the long term.
Did you fasten your panels to solid decking, with some sort of underlayment?
The ice and water shields are absolutely excellent at fulfilling their designed purpose. The problem though, even with Cadillac material such as Grace, is that they do not breathe at all. So any moisture present during installation...remains present.

As long as you have proper ventilation, I would not stress at all about moisture developing after install, as Ice and water is very waterproof (double edged sword). In all reality, products like Grace could suffice as water proofing your home alone, except for the fact that UV radiation will burn it up and the wind may do some work on it.

My advice if you want the most bulletproof roof:

IF your decking is dry (not bone, but very dry)
IF your panels are dry
IF it doesn't rain or drizzle a smidge
THEN you can just put on synthetic ice and water shield and your steel panels.

If there is any wetness, rain, etc, then install 30# felt over the ice and water. That will provide an excellent vapor barrier and allow water to weep out.

And of course, if you are not in a climate where ice damming is a concern, just go with 30# and steel regardless off how wet the product is during install.