I know this has been touched on a couple of times, but I’ve not found a good discussion yet. Regarding nail placement on lap siding. I’ve looked through older discussion and my questions have not been addressed yet. I worked for a couple of contractor in the Portland, OR and Vancouver, WA area. We resided several larger houses with cedar lap. Both contractors had me blind nail the siding. We used 8″ siding with 6″ reveal. Every so often we would face nail a trouble spot that didn’t suck in. It looked nice with few exposed nails. I recently did a friends house using this method and one of her other friends got all over me about it in front of the home owner. I was just doing it the way I had leaned. So, I’ve been researching it since then. What I’ve come up with so far is that face nailing (through the face just above the siding below the one being nailed) is required for high wind areas and larger siding (ie. 12″). It seems to be the common way to nail. But, it seems that using 8″ siding with 6″ reveal in an area that is not a high wind area blind nailing is sufficient. I have not been able to verify this in my books or from the mill. I’d like to hear your thoughts.
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You'll get plenty of replies on this. Wood is not stable and you'll have problems with it cupping, forget the wind. I would not blind nail any wood, even fiber cement lap siding companies require face nailing over a certain exposure, and FC is stable.
I would not want it blind nailed
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Why? I am interesting in the reasoning for the answers. I really don't care what people would or wouldn't do so much as why they would or wouldn't do. I don't mean this in a sarcastic or disrespectful way.
If blindnailed, I can't possibly imagine it lying flat all of the time, even if you used 100% clear, vertical grained material that was back primed AND painted. Maybe it'll look flat after a dry spell, but if there is any moisture variation between the front and back faces, it WILL curl.
That's a good point. I have gone back and face nailed a couple of pieces that curled outward on the bottom. One other question you guys may have experience with is cupping before installation. I just did a small project where I face nailed by hand. But, the siding (cedar again)had cupped before I installed it. The crown was outward so when I face nailed I had a problem with it splitting when I tried to suck it in with the nail. I tried to nail 6"-8" from the edge and still had problems. A lot of the people around here can't afford top of the line cedar so this isn't the best stuff.
In my climate, claps that size would warp right off the wall in a couple of years.
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The problem in northeastern Washington state isn't humidity like a lot of areas, but temp. differences. Here in the mountains it can be more than 40 degrees difference from day to night. This causes a lot of movement. I did have trouble with some of the siding cupping. I had to fix it. That is part of the reason for this post. I don't like having to fix my own work and I don't like doing a job wrong. But, I still have holes in my knowledge. That's what I like about forum like this. It's like having hundreds of friends that are contractors. Hopefully we can all learn from each others successes and failures.
That's what I like about forum like this. It's like having hundreds of friends that are contractors.
I agree completely. That's why this forum can be such a great resource.
By the way, have you ever looked closely at the siding that was cupping on you? It's most likely flat grain. I know that the clear cedar is expensive enough as it is without then specifying VG only, too! But if someone were to ask me to put on something like an 8" board, I would advise them to use CVG or select a different product that was more in their budget. In my experience, CMG works well for the little profiles, like 1/2 x 4 bevel, but beyond that I have reservations.
Hope that helps.
The were not a lot of options. This was a single mom with little money. She is selling the house. The house was half done (the easy to get to half). I did the second story over a glass greenhouse in feb. with lots of snow and ice. I did all the hard to get to places. No one else would do it for her. They all said it was too dangerous. They were right. But , I came up with ways to get to all the places. Also, the house is poorly built. It was built by 8 different groups of hippies back in the '70.
That's why we're all here
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Here's a hole in your knowledge you can fill ;-)
Temperature differences don't cause wood to move.
But they do cause changes in relative humidity, which will cause wood to move.
Even in high desert like eastern WA, there is moisture in cool night air which is absorbed into clapboards exposed to hot, dry sun all day. The moisture expands the surface of the wood, making it curl in. Then the sun dries the moisture out, or drives it farther into the building, making the clapboards curl out.
Nailing the clapboard near the bottom lets the wood do its dance between courses, without curling.
Temperature differences don't cause wood to move
Just about any material will expand or contract with temperature changes. But I think you're right in pointing out that changes in humidity are the dominant part of the equation when working with wood. And you're also right in pointing out that the fall in temperature at night leads to higher relative humdity levels, of course.
Check out http://www.amazon.com/Understanding-Wood-Craftsmans-Guide-Technology/dp/1561583588
You're right, temperature affects all materials, but the amount that it causes wood to move is infinitessimal compared to movement due to moisture.
Mike,
Do you happen to own the book that you linked?
I'd be interested in knowing what the actual numbers for humidity-related expansion are for cedar (or other woods, too, for that matter).
One of my old texts gives a few coefficient values for thermal expansion. It'd be interesting to compare the numbers and see how much worse the humidity-related expansion really is.
Yes, I own it, and I'd scan and post pages here but I don't want to violate the author's copyright. He does say that "In the grain direction, wood changes dimension by only about 2 millionths of its length per Farenheit degree change in temperature.... Perpendicular to the grain, the coeffiecient of thermal expansion is as much as ten times that of wood parallel to the grain direction."
He also says that the approximate shrinkage of western red cedar as a percent of green dimension, from green to oven dry in the tangential direction, is 5.0. In the radial direction its 2.4.
If you're interested in wood's material properties, it's THE book to have. I highly recommend it.
Mike,
The thermal expansion values you cited jibe with what I've read before. That is, expansion along the length of the board is in single digit (millionth) percentage points, and expansion across the grain can be in the 30-50 (millionth) percentage points.
I was looking around on the net a bit and found numbers related to shrinkage due to the drying process. They were also as you cited.
However -- lacking a text to explain it -- I don't know how to interpret the moisture shrinkage numbers. Going from a green (i.e. sopping wet) state to being dry is a radical change. This is obviously a far greater change than wood would undergo due to daily or seasonal humidity changes.
Is there anything in the text that relates to a more "real world" moisture change that we as woodworkers would be likely to deal with?
Yes, the formula is:
Change in dimension due to shrinkage = (Initial dimension)(Total shrinkage percentage)(Change in moisture content)/Fiber saturation point
Total shrinkage percentage is one of the values I gave you for red cedar, expressed as .050 or .024.
The average value for Fiber saturation point is .280.
Ragnar, the USDA Forest Products Lab has the engineering data for nearly all, (if not all), woods commercially produced in North America on their website.
http://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr113/fplgtr113.htm
It is a great free, (if you don't count the taxes you pay to support it), resource.
I know math isn't everyone's favorite topic, and it has a lot of the materials science and equations that come from it in it. But don't let that scare you off, the tables and text are pretty straight forward.
I know math isn't everyone's favorite topic, and it has a lot of the materials science and equations that come from it in it. But don't let that scare you off, the tables and text are pretty straight forward.
Thanks for the link -- I'll check it out when I have some more time and see if I can figure out just how much cedar siding may want to expand.
Math scare me off? Did you forget that we were discussing engineering in another thread? Math is definitely my friend. ;)
I was trying to keep it semi invinting to the rest of the crowd. Most people know a lot more math than they think they do, but are frequently scared off if they see the math. And, if they just slow down read the text and think about it they can learn, understand, and use the information.
And, the Wood Manual is pretty much the dfinitive work on the propoerties of wood, and how it reacts.
Thanks for the explanation.
By the way, do you have any pictures of your fish screen projects that you can post over in the "photos" section?
Now that you ask again, I feel like an idiot. I spent the whole day touring different sites with anew engineer from the National Resource Conservation Service, showing him the different types of screens we have installed and explaining the positives and negatives of each type. It would have been the perfect chance to take pictures and post them.
I'll have to see if I can have him email me copies of the pictures he took. That, or make an attempt to find some on our network drives at work.
It's funny that you came up with that book. I put it on my "must have" book list earlier today. The reviews were great for it. You must recommend it too.
I installed shiplap siding on my garage and after reading these posts I fear I may have done it wrong. I should have primed or primed and painted both sides and ends? I should have nailed the siding top and bottom of the face all along and not in the bevel only to try to hide the nail because it could curl? and the nails should be what size? ring shank framing nails ok? I used my nailer. thanks-worth exactly 2 cents!
Well,There is lots of siding up and lasting that has not been back-primed.But for it to last longer, with less chance of it curling and to be more certain that the paaint will not peel off in sheets, it is best to backprime. I like factory pre-primed because we have bad weather here so bare siding can get wetted several times and have some UV damage as well by time it gets primed after the install. Also important - when you wait until it is hung to proime it, you end upo with a chance that the unpainted paortion under the lap will become exposed when the woood shrinks later and need more paint.The reason paint can peel off if not backprimed has to do with moisture moving out through the wood siding. It used to be reall bad with opil paints whih made a skin that trapped the moisture so that it woud boil right up under the paint skin. Latex will let moisture breathe through toi in a limited manner.You should NOT nail top and bottom. As you can see from this thread, there are some who believe in and practice top nailing. But it does not work for me here. If you naile two nails and then the board shrinks, you have stopped it from moving so the only choice it has is to split along the grain in the middle between the nails. Then more rain blows in.Ring framing nails from a gun for siding?!Shucks, I been had, you been pulling my laig!
go on now son....
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We resided several larger houses with cedar lap
I'm kind of confused by this. All the "lap" siding I've encountered has been an "engineered" product like OSB, cement fiber, etc.
I looked up "cedar lap siding" on the net; some manufacturers identify "cedar lap" as horizontal ship lap.
Where I live, the horizontal cedar siding is known as "bevel siding", due to the bevel shape in cross section.
What style of siding are you specifically working with?
Beveled siding and lap siding are often used interchangeably. Shiplap has a rabbeted joint at the overlap. One reference that I am looking at right now is Building Construction Illustrated by Francis D.K. Ching. I have learned through the years, however, that the same thing is often referred to by different names in different areas. Just moving from Alaska to Portland,Or and then to north east Washington; I have gone into the lumber yard, in my new home town, and asked for something by the name I had always used and got a blank look in return. I think with the internet and all the books and magazines we have now, that is changing.
Beveled siding and lap siding are often used interchangeably
That may be the case now, but I'd attribute it to popular misuse. "Beveled siding" is a pretty descriptive term, as it refers to the cross section of the siding, of course.
Anyhow, back to your original post -- are you refering to a cedar siding with a beveled section, or a rectangular section?
The reason I ask is that I think beveled siding is a poor candidate for blind nailing. In addition to what others here have already said, blind nailing in a beveled section results in driving the nails through the thin (and therefore flimsy and structurally vulnerable) portion of the board.
With "lap siding" (as I understand the term), the siding is of uniform thickness. Therefore, nail placement is not as critical --- at least from a strength perspective.
A final note: cedar manufacturers specifically advise against double nailing beveled siding. If someone blind nails and then has to go back and drive additional nails to hold down the lower edge, that results in double nailing as the manufacturers define it.
Edited 6/14/2007 4:28 am ET by Ragnar17
Manufs recommend face nailing with spiral or ring nails for pullout resistance. No nailing through lapped areas.
http://www.wrcea.com/cedar-products/cedar_siding/installing_siding/lap_siding.htm
I'm doing a vertical applied channel siding job at the moment, with 1x8 cedar. It's being stained with a forest green solid stain so it's easy to touch up the nail heads with a bit of stain and they pretty much disappear, although not sure of the longevity of stain over galvanised steel.
Slykarma,
I can't imagine that the OP is using the same type of "lap siding" that you are (aka shiplap). It seems nearly impossible to blind nail ship lap since there is only about 3/8" or so of coverage at the top.
moon.... what is "cedar lap" ?
is it cedar or fibercement ?
I am referring to siding made of cedar. And yes, it is beveled.
I've appreciated all of your responses so far. I am wandering, though. Does anyone out there blind nail or was I just unfortunate enough to learn from a couple of guys that were exceptions to the norm. I haven't done a lot of siding jobs over the years. And we always face nailed hardie siding, but I always thought that was because we painted it. Anyway, thanks so far. I've been reading up and this issue and talking to a lot of other contractors. So far the consensus is pretty clear.
Several years ago there was an article in FHB. Forget the author but he was/is a regular contributor.He advocated face nailing wood beveled, and also didn't think it was important to hit the studs...just use ring shanks into the sheathing.The article generated lots of criticism from those who felt the technique would result in splitting. I tried it on my last home...used WRC that was good and dry...recall it being 7.5" with 6" exposure...never had a split. Todd
He advocated face nailing wood beveled
It's amazing to me that "his" approach would be widely criticized. It's been standard practice with bevel siding for more than 100 years. And it's also what the cedar manufacturers recommend. There's usually even a little picture attached to the bundles of bevel siding that clearly communicates the installation method.
Blind nailing is recommended for lap siding.
Maybe it's the confusion between the terms "lap siding" and "bevel siding" that have generated the problem.
Humm...maybe my terminology was wrong or had an unclear description, yup. Point is, the author felt that nailing through both pieces (upper and lower) was just fine.The little direction sticker on my WRC stated that the nails on the top piece should clear the piece below. Didn't check with the industry bureau but bet that's what they say, too.Todd
Point is, the author felt that nailing through both pieces (upper and lower) was just fine.
If that's the case, then I can understand why the article received criticism. You are right in pointing out that the nails are supposed to clear the course immediately below them.
Putting in two rows of nails is called "double nailing" and is technically a no-no. Mike Smith posted a brief explanation as to why it's not recommended.
Regards,
Ragnar
""Does anyone out there blind nail or was I just unfortunate enough to learn from a couple of guys that were exceptions to the norm.""I'd say you were unfortunate, Sorry, I think you picked up behind someone who learned on hardi siding, which can be blind nailed, and tried to transfer that practice to bevel (AKA Lap-) siding. Live and learn. "The proof of a good carpenter is more in how little the mistakes slow him down than in how few mistakes he makes" ------------------
"You cannot work hard enough to make up for a sloppy estimate."
moon..... the time honored correct way to fasten beveled siding is to face nail just above the lap
so...if you are doing 8" beveled siding, it is probably 7 1/4" and you exposure is 6"
the nail will go 1 1/2" above the butt , just clearing the course below
beveled siding likes to expand and contract with the change in humidity, so you only want ONE row of nails holding it, then it can expand and contract without splitting ..
with a blind nail, you will accomplish this also, often termed "hanging claps".... as in: "what are you guys doing ?"
"we're hanging claps"
the problem with blind nailing an 8" clap is the bottom 6 1/2 - 7" is doing just that.. "hanging"... it won't make for a very neat job and clapboard siding should be a "neat job"
we used to fasten our claps with bronze ring-shank boat nails until we got into siding guns... now we use a medium to small head ring shang SS siding nail.... face nailed
the reason i asked if this was fibercement, is because a lot of the mfr's call their product "cedar mill".. anyways. with FC we blind nail with Hot Dipped 1 3/4" roofing nails up to 6" exposure,
for exposures beyond that , we face nail with SS siding nails, in the same location as wood beveled siding
a lot of the mfr's call their product "cedar mill"..
Yeah, I noticed that when I was searching online for lap siding. Nothing like calling a cement lap product "cedar mill" to clarify things. ;)
I was wondering why you asked if it was cedar. Thanks for that explanation.
Well, here's my 2 cents.....
Clapboards, specifically refers to a siding originally from New England, applied horizontally, where each succesive row laps the previous row....face nailed.
lap siding was a term applied to a plywood siding of variable widths, applied horizontally....the term appearing most commonly after WWII....face nailed.
Horizontal sidings includes board a rectangular profile, applied in a Board and Batten fashion, Board on Board fashion, or Clapboard fashion.....face nailed. Channel/rustic a rectangular profile,with two rabbeted opposing edges, applied horizonally or vertically, installed in a lapped fashion.....face nailed. Drop available in multiple profiles in either a ship-lap or T&G style and either blind (T&G) or face (ship-lap) nailed. Bevel available plain or rabbeted edge, installed in a lapped fashion....... face nailed.
Other names/styles "Bungalow" (also called "Colonial") "Dolly Varden" " Log Cabin" and "Tongue & Groove"
All these are horizontal sidings which are applied in a lapped fashion (except for the T&G, technically speaking) and all are recomended to be face nailed (except the T&G versions).
The "popular misuse" of terms is probaly the best description of what now exists, in terms of terminology, perpetrated mostly by product manufacturers/distributors.
Just my 2cents worth
Geoff
P.S. to moonmlns: beveled siding should be face nailed IMO
Edited 6/15/2007 1:25 am ET by Geoffrey
Geoff,
I've heard of "German siding", too, but I have no idea what it might be. Got any guesses?
Hi Ragnar,
I'm thinking (guessing really) it's probably one of the drop sidings, since there's about 8-10 profiles of that style that I'm aware of.
Geoff
You ever hear of a train siding?
You ever hear of a train siding?
Yeah, I've also heard of spurs. ;)
<You ever hear of a train siding?>
Actually it is called "car siding" and is intended for use on freight cars. It is tongue & groove material, typically 2 inch (true thickness back in the 1900s; today the typical 2x thickness). Often times it is finished smoothly on one side to make the outside of the car look good. The inside gets banged up really quickly.
Car siding is typically installed vertically.
(I just finished priming a whole load of new car siding for a freight car that I am helping restore. The person in charge of the project had a heck of a time getting good, clear fir for this project. Then we ran stuff through the machines to make the tongues and grooves.)
I was just being a goof. But I have a friend that does volunteer work restoring old RR cars for the Whitewater Valley RR. http://www.whitewatervalleyrr.org/main.php
And I apologize if my response sounded snide. I did not intend it to sound that way.
And, indeed it is sometimes called train siding but the more standard term is car siding.
You didn't sound snide at all. I was thinking of a siding where the train is off the main tracks, like a spur. Sometimes I try a one liner that flops.
Sometimes I try a one liner that flops
Hey, I got the joke. Maybe John's just a tougher audience.
MarkH and JohnD1,
I actually have heard it called "box car siding"
Geoff
How do you train siding not to do tricks?You hire a german siding expert to nail her gud'n'tieghtBadaboom
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http://www.buffalo-lumber.com/dutch-lap-siding.htm
I guess that's "Dutch" like the "Pennsylvania Dutch", who are really German. ;)
Having three names for the same thing sure can confuse things. The original part of my house had that siding in pine before it was covered with a wonderful vinyl. (:-(
Greetings. Although not covering cedar, check out "sidings and applications" at http://www.calredwood.org/ref/lit.htm