# Lap Siding: How (Not) To Install Hardiplank And The Like

In a comment on my first "how (not) to" hub--How (not) to install a low-flow toilet--I was told, "you are so not 'Canada's worst handyman!'" This might seem self-evident, given that I live in Atlanta, but I chose to take it as a compliment to my skills anyway. (And I suppose that I should explain, for those not versed in Canadian lore, that "Canada's Worst Handyman" is a popular 'reality' show.)

However, I do find that I have a tendency to discover at least a few of the pitfalls in any given project the hard way. The bright side of that is that I can then share those pitfalls with you, dear reader, and save you the hassle. So, since you are reading this, perhaps you need to do some siding? OK, then, let's start.

Front view, siding in process. You can see how unsightly the sheathing was! (Though the supplier probably appreciated the advertising.)

As you can see, we have a shed that was seriously in need of siding; how our neighbors put up with this for such an embarrassingly extended time I don't know!

The first thing is to estimate the materials needed. At the store, the salesman told me that he needed to know the square footage of wall to be covered. Time for some math. . . The shed is ten by twelve, with eight-foot high walls, and with two doors. So multiply the height times the width for each wall, and subtract the area of the doors.

The triangular area of the gable ends might seem intimidating at first, but the geometry works out such that you can just multiply the height of the gable by the width of the wall. ("Height of the gable" means the distance from the peak of the gable down to the line where the eaves meet the top of the wall.) Adding it all up, I found I needed a little less than five hundred square feet of board. Since I wanted extra board for another small project, I rounded up to five hundred; that worked out to be 70 12-foot boards.

But what sort of boards, exactly? There are a number of options. However, this Hub isn't about the virtues of each. We chose Hardiplank, a popular and durable choice today. It was pretty affordable, as well, since our building supply store sells a couple of types of Hardiplank basically as a loss leader (less than \$5 per 12-foot length, as of this writing.) You can read more about the environmental virtues of Hardiplank at this Hub:

Whole and broken Hardiplank.

## Handling Hardiplank

The photo above shows the Hardiplank on a pallet--and brings us to the first "how not to." Hardiplank is durable--but not if you handle it incorrectly. How did those boards in the center get broken?

I discovered a few ways to do it:

--You can lift the board with your hands too close together, putting too much stress on the center of the board;

--You can handle too many planks at once, and the weight of the upper boards will tend to snap the lower board. When they give way, the upper board will "flop" and break too;

--You can move too abruptly, especially when lifting one end of the board, as when placing it on your work table.

So, when handling Hardiplank, keep your hands well apart to spread the pressure, move deliberately, and move boards no more than two at a time.  If you stick to one at a time, you can follow the Hardie company recommendation by carrying them on edge.

And if you're like me, remember that swearing at broken board doesn't mend it, and can be quite embarrassing if those long-suffering neighbors happen by.

Corners with trim installed over the tar paper. The duct tape has come unstuck on the far corner, causing a sag.

Applying the siding starts at the corners. That's where you put the trim pieces, which serve to cover the ends of the siding boards. There are different sizes of Harditrim available, but 1' x 4' is pretty standard, and that's what I chose. I also followed a time-honored practice by covering the corners first with tar paper. The concept is to keep out any water that may come through the potentially vulnerable corners. I'm not sure it's really necessary, but it's also cheap and pretty easy, so why not?

There is a small "how not to" here, though--if you're siding over foam board, as I was, don't try stapling the tar paper. It just won't hold. I ended up using duct tape to hold the tar paper until the boards went up, thereby securing the paper in place permanently.

Speaking of securing the board, you have choices of fastener, too.  There are siding nails intended for the purpose; but roofing nails and coated sinker nails have their adherents as well.  The roofing nails have a tendency to bend and damage the siding, in my experience at least.  And the sinker nails, though they work well, don't meet the corrosion resistance recommendations of the Hardie company.

Detail of corner. The Harditrim boards will be cut off evenly at the bottom; you may be able to avoid this step by careful measuring. Note also the duct tape temporarily securing the tar paper.
Piecing corner trim. Note the downward-sloped 45-degree cut. You'll note that I chickened out on "blind-nailing" the boards--I didn't trust that quarter inch overlap.

If you are cheap, er, I mean "frugal," you can piece corner pieces to reduce waste, as shown in the photo above. I chose the corner which will not often be seen close up to piece together. Use 45-degree angle cuts, sloping downward to avoid any tendency for water to seep into the joint.

The saving for the poorer appearance and slight extra work was about \$9. Was it worth it? You make the call!

By the way, when nailing Harditrim you should plan on drilling pilot holes for the nails. It's tough to force a nail through the material without one, and if you succeed--most likely two or three nails later--you'll tear up the board quite a bit.

(Yes, I discovered that the hard way, too.)

A primed piece drying in the sun. I've tried to tone down a very, very bright scene!

While some Hardiplank is pre-finished, the board I chose is not. It must be primed and painted. I chose to cut pieces to length first, then prime them using a roller before installing them. The finish coats were then applied using brushes. I chose water-based Kilz for primer, and a semi-gloss latex exterior paint for the finish coats.

The advantage of this work flow is that it's a compromise between having to work far ahead with your boards on the one hand, and brushing all coats onto installed siding on the other. I don't like to cut too far ahead of where I'm installing the siding boards, as no matter how careful you are, there will be variations in the length needed as you ascend the wall. But if you apply all the coats first, you'll be waiting a long time for paint to dry. Besides, you need at least one coat on top of the caulk and nail heads, anyway.

On the other hand, primer can be applied to a pre-cut length very quickly with a roller--probably in just a couple of minutes. And it will usually be dry enough to handle in half an hour, or even less in full sun, during which time you can be cutting and installing siding. So I'd cut and paint three or four pieces at a time, and put them in the sun to dry, supporting them on a couple of Styrofoam blocks I hadn't yet recycled.

By the way, it's best not to leave your Hardiplank exposed to the elements--especially rain.  It seems to infiltrate the board some, and make it even more prone to breakage.  And it definitely can result in soiling and staining.

Dirt washed onto board by rainsplash.
Cleaned up (mostly.)

Of course, you must start at the bottom of the wall, overlapping boards as you go--most Hardiplank is intended to overlap by an inch and a quarter. Use a level to mark where the top edge of the board will be--I marked directly onto the trim piece, which worked well since that nice white primer made for an easy-to-see mark.

It was convenient to mark four boards or so ahead. Recheck level frequently as you install the boards!

Also, keep in mind that you want to maintain the same spacing on each surface. If you don't, the appearance at corners--or on opposite sides of doors--will suffer badly. (The board on each side of my front door could line up better, if you look closely--but I'm not giving you a close up!)

Long pieces require you to pre-place a support--sometimes called a "buck"--at one end. The buck should be set carefully, so that it supports the board within a half-inch or so of the correct level. Place the board on the buck while you nail the other end in place, then go back and fasten the "bucked" end, correcting the level as you do.

You can buy special brackets for this, too. But if you don't do a lot of siding, it may make more sense to use various improvised props, as I did.

Starting a side. Use your level carefully and often! Installing long pieces single-handedly means using a "buck" to support one end. You can see a piece of 2 x 6 used for this in this purpose at the far end of the top board.
Tools for cutting boards. Special snippers are also available.

Speaking of cutting the board, my main tools for this are shown above. It's all very normal: a tape to measure length, a carpenter's square to keep angles "right," a circular saw (supplemented by a jig saw as needed), and a small surform plane to clean up the ends a bit once you've cut them.

A regular crosscut blade works fine, but does dull quite a bit cutting Hardiplank. It would probably have been better to use a masonry blade, but I didn't think of this until my blade was already dull. If you try the masonry blade, let me know how that works!

I'd recommend a dust mask when cutting Hardiplank. I know Hardiplank is supposed to be friendly to the environment and all, but is it really a good idea to inhale cement dust?

The James Hardie Company suggests not, too--see their website for more detailed instructions. They are particularly concerned about your safety if, unlike me, you do your cutting indoors rather than out.) Their Hardieplank page can be found at the link below.

Another improvised "buck."

As the picture above shows, sometimes it's not enough just to cut a plank to length; you will probably also have to trim out bits for doors, windows, or light fixtures.

Start by measuring carefully and repeatedly. The old adage is to "measure twice and cut once," but twice isn't always enough for me! Allow a little extra--say, an eighth inch on each side of an opening. (Think carefully about which way the allowance needs to go--it's surprisingly easy to apply it backwards.)

This door opening was done by making the long cut first as a "plunge cut." Keeping the ends attached ensures that the board doesn't break. (A plunge cut is made by holding the blade of the circular saw above the material, keeping the front edge of the saw's base plate firmly in contact. Start the saw, then carefully pivot the blade down onto the cut line you have marked.) The short cuts can be made easily with supports on each side of the cut.

As the second photo shows, I propped the work piece up above the work table, setting the saw blade to a shallower depth above the work table surface. (See picture three for a closeup of the blade being set to depth.)  The corners were finished with the jigsaw, as shown in the bottom picture.

The long "plunge cut."
Setting blade depth for the plunge cut.
Setting the supports to keep the blade clear of the work surface.
Finshing the plunge cut with the jigsaw.

It's jumping ahead a bit, but there's another trim that you may need to make:  the trim to fit a roof gable.  I know I had trouble doing this, until I learned this method from Ian Denham, of The Mountain retreat, near Highlands, North Carolina.

Use a level to set a baseline for your gable measurements.
Using a carpenter's square, find the place where the distance from baseline to roofline ("rise") equals the width of your board. Mark it.
Measure the distance from the eave line to the place where you measured the "rise." This is the "run."

As shown above, begin by marking a level line horizontally from the point where the roofline meets the edge of the wall. I call that my "baseline." Use a square to find the point where your baseline's distance from the roofline is equal to the width of your board. Finally, measure the distance from this point back the point where you began the baseline. I call this the "run."

When you are ready to cut your first gable board, you simply measure the distance of the "run" from the top corner of your siding board, mark it, and use a straightedge to draw a line back to the bottom corner of the board. This will be the correct angle to cut.

(Of course, most times it won't work out that the cut line needs to be exactly at the corner of the siding board. Then you have to adjust the line upwards, either by cutting the line directly on the board, then trimming the excess, or by making a template using a waste piece.)

That was the situation with my project, and the resulting cuts are illustrated in the photos below. For the smaller cut, it was easy enough to make the cut beyond the end of the work table; for the larger, the work piece was raised above the table using small blocks.

Marking a small angle using a waste piece, previously cut, as a template.
Trimmed off.
A larger "gable" cut in process.

A few miscellaneous points remain. One is that you need solid wood behind the siding to nail into. For the most part, that is not a problem; studs--the vertical 2 x 4 pieces within a wall--are spaced 16 inches apart, which means that there is likely to be a stud close to where you need to nail.

But there are exceptions. One exception can happen at corners, as illustrated in the photos below. The width of the stud in the corner is less than the width of the trim piece on the outside of the wall. That meant that there was no overlap between the two. So it was necessary to provide a nailer to secure the ends of the siding boards.

Fortunately, this isn't very hard; cut a 2 x 4 to the correct length, tap it into place as shown, and secure it with nails driven at an angle through the corner of the 2 x 4. (This is called "toe-nailing.") Voila! A place to drive your nail.

The inside view of the shed corner. Note how the stud on the right stands out from the intersecting wall, spaced away from it by the intersecting stud. No wood backs the siding board.
Nailer in place. Note the nail being driven into the top corner ("toe-nail.")

Another issue is the tolerance between the trim board and the siding itself.  As shown below, it's standard to leave a small space between the two, which will be filled with caulking.  This space makes installation easier, and makes it less likely that siding will bow out later.  I used a standard latex caulk for this, applying it according to the manufacturer's instructions.

Caulking in process.
Ready to paint. Note the large brush with the smaller trim brush.

If, like me, you choose an unfinished siding, you are going to need to paint once the caulking is complete. I like a semi-gloss finish for most exterior projects, but that is up to you; many folks like satin or even eggshell.

(For those uninitiated in painting lingo, these terms refer to how "shiny" the finish will be. The shiniest finish is "gloss;" the flattest is called "matte." In addition to affecting the preferred appearance, finishes affect the ability to clean a surface as well; shinier surfaces are generally a bit easier to clean--though they may also sometimes show dirt more clearly.)

Although a roller is just the thing to prime the board quickly, it is not so useful for painting a lap-sided wall--the wall is not flat enough!  So, unless you have a spray rig, you will be using brushes.  The larger the brush, the faster you can cover an open area, so if you are like me you may be tempted just to charge ahead with the biggest brush you've got.  (The larger one in the photo is a 4-inch brush.)

Resist this temptation.  The results will be better, and you will actually save time, if you use a trim brush to paint edges and corners before attacking the wide-open spaces.  The pictures below illustrate the "better results" part.

Bad cut-in at door molding, done with 4-inch brush.
Good cut-in at door molding, done with trim brush.

Here's an illustration of the two-brush process. Here, the edges and corners have just been done with the trim brush. (Painters call this "cutting in.") Not only is it neater to do with the smaller brush, it is much faster. Finishing the open areas with the big brush is very, very quick once you have completed the "cutting in."

Normally, you are going to need two finish coats. If you're lucky, or very meticulous with your first coat, you may be able to get away with just the big brush for the second coat.

Mostly.

At this stage, not so pretty. But it's still the way to go.

So, how did it work out, you ask?

I'm pleased. The job isn't perfect, but looks decent. (Finally!)

Doing it myself certainly held the cost down greatly. It took about 45-50 hours to complete the project from start to finish. (Your results, as they say, may vary--you may be more or less efficient and/or energetic than I am.)

Just be careful how you use the ladder--but that's a subject for another Hub!

Rear of shed.

## More by this Author

tyty 4 years ago

You're horrible at every step involved... Hire professionals, please.

Doc Snow 4 years ago from Atlanta metropolitan area, GA, USA Author

You paying?

I make the mistakes so others don't have to--and I'd dispute the 'every step.' The final result is quite presentable, thanks very much. Could professionals have done it smoother and faster? Of course. Would it look significantly better, or last longer? I doubt it.

dgg 4 years ago

HardiePlank should overlap 1-1/4", not 1/4".

Doc Snow 4 years ago from Atlanta metropolitan area, GA, USA Author

You are correct. I've edited the text to reflect that fact.

Thanks for spotting the error and taking the time to comment.

John 4 years ago

Hardie should never be fastened at the far sides and then nailed in the center. Always start from one side and then nail continuously to the end. The butt joints where Plank meets should be flashed with an 8x8 pice of metal, and all edges should have a 1/8 gap.

Doc Snow 4 years ago from Atlanta metropolitan area, GA, USA Author

Thanks for the tips, John! I appreciate you taking the time to make them.

I'm curious, though--what happens if you nail first at far sides? As mentioned in the text above, that's just what I did, and I haven't noticed any bad effects. Perhaps I don't know what to look for? But the planks are not sagging, nor buckling, nor much of anything else that I can see. Perhaps I dodged a bullet--but I'd love to hear more on this point.

AB 4 years ago

Get the Hardie saw blades. Home Depot carries them with the other circular saw blades. Wear a respirator when cutting it. Flashing behind butt joints can also be done using a piece of house wrap. Butt joints must be caulked. I recommend polyurethane exterior. Pricier and harder to find the good stuff. Find a building supply store for pros. I get mine at White Cap or on-line. Don't forget to prime the cuts. I prime my boards on both sides before I cut. Then I just touch up the cuts with primer and install. Roofing nails are used when you have a roofing nail gun.

Doc Snow 4 years ago from Atlanta metropolitan area, GA, USA Author

AB, thanks for coming by and giving us all some pro-level tips!

Sure appreciate it, and I suspect my readers do, too.

JG 3 years ago

Thanks for posting the "Not to do" items. This helps to understand what can/will go wrong so I'm prepared for it.

Doc Snow 3 years ago from Atlanta metropolitan area, GA, USA Author

That was the idea--so glad it helped you out!

RTalloni 3 years ago from the short journey

We're planning to use hardiboard soon so this was an interesting read-thanks. Comments interesting, too. Good for you for a nicely finished shed. Like the brown among the trees.

Doc Snow 3 years ago from Atlanta metropolitan area, GA, USA Author

Thanks, and again, glad it offered some food for thought. I agree with you about the comments; there was some really good information there. I really appreciate the folks who took the time to share their knowledge with the rest of us.

Brett 3 years ago

Nice write-up. I appreciate it. Tyty gets two thumbs down for being a butt head. Not everyone is able/willing to hire a "professional." And, I'll add that many that I've encountered in the construction business pretend to be professionals but don't even come close to meeting that level of service.

Doc Snow 3 years ago from Atlanta metropolitan area, GA, USA Author

So true that hiring a pro is not always an option. (And true, too, that some whom you might hire don't live up to the name.) I think the key is using good sense and being realistic about both your abilities and about the consequences: if I screw up siding my shed, I may waste time or money or both. But if I decide to, oh, run a new gas line and make a mistake--well, that's a whole other level of potential disaster, isn't it?

Most errors, though, are "recoverable." And that's worth knowing.

Thanks for commenting--and for sticking up for this amateur!

Eric Myers 2 years ago

You are so right. I do siding for a living...I put together this short video of some of my work....What do you think?

Doc Snow 2 years ago from Atlanta metropolitan area, GA, USA Author

What do I think? I think you're in the middle of a promotional campaign, and that your video looks good. ;-)

Could use some nicer music, though. I can help you with that:

ispeakmusic.com

snowonmusic.com

Thanks for commenting!

Hi Doc,

Enjoyed the article about your project. Sorry I am new here but thought you would like to see this story I found on an old farm home in Illinois that was made over using Hardie. My husband and I found it before coming to this site since we are looking to remodel our home. Love to get your thoughts on that because we are looking to do somethign similar.

http://www.abedward.com/james-hardie-siding-contra...

Doc Snow 2 years ago from Atlanta metropolitan area, GA, USA Author

Thanks, Allie. It's an attractive exterior, isn't it? (Though I'd hesitate to use the word "restoration"--looks more like a redesign, albeit one that's stylistically sensitive (to my eye, at least.))

The great thing about the Hardie is that it should last the family for their tenure in the home, even with less-than-meticulous maintenance. And if you are going to peel the siding to restructure the wall for energy efficiency anyway...

emmysmith 2 years ago

This is an incredibly detailed post! This is just the information that I needed, thank you so much! My husband has been wanting to do some lap siding on our home for a while now. I didn't know what he meant by that so I decided to do some research before we went for it or not. I will have to show this to my husband, I think it will help help him when he is doing the installation.

Emily Smith http://www.sidepro.com/reside/products/

Clay 11 months ago

Can I put 1x4 vertical strips every 12" over existing wood siding and hang hardi plank over it. The wall has no windows or anything that needs trim. I will house wrap before I put the 1x4's

Doc Snow 11 months ago from Atlanta metropolitan area, GA, USA Author

Clay, I'm honestly not qualified to give you a firm answer on that. It sounds like a workable idea to me, but I think you might want to consult with an experienced contractor. (In my experience, they are busy folks, but they also recognize the value of building good will, so you might well be able to get some good guidance for little or no cash outlay.)

If I were going to do a project like yours, I know I'd check carefully on the condition of the existing siding. You don't want to enclose any rotted siding, for sure!

And that brings up my main concern: making sure that the structure is properly ventilated and/or structured for moisture handling. In the northern tier of the US, and in Canada, my 'native land', the standard practice has been to put a moisture barrier on the 'warm in winter' side of the wall insulation; that way, the insulation (still most typically fiberglass batting) stays dry. Put your vapor barrier on the outside of the insulation, and you'd get condensation forming on it.

Here in the south, where I live now, a good many folks in construction seem never to have even heard of that practice; cooling living spaces rather than heating them is the predominant issue. And they sure do use that house wrap you are talking about, as a casual glance past just about any residential construction project can show.

Bottom line: my guess would be that you will be fine, but you might want to double check with a pro who is familiar with local conditions and regulations.

One last thought, really a question: would there be a benefit to you to add some insulation to that wall while you were at it? You could get probably something like R4 with something like this product, which is actually R5 for a 1-inch thickness:

http://foamular.com/foam/products/foamular-sheathi...

And in theory, you could possibly offset the 1 x 4 furring strips from the studs to reduce thermal bridging through the wall, though you'd need to look at the structural adequacy of that. But I have no idea how the existing wall performs, or what your environment is like, so I don't know if there would be a reasonable benefit for the extra work and material. Still, it's a thought.

Anyway, good luck with your project!

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