HARDIPLANK cement siding
I’m starting to build a new workshop and planning to use HARDIPLANK (cement) lap siding. Do any of you have any experience with it? Their spec sheet says butt joints should have “moderate contact or maximum 1/8″ gap.” They also call for 1/8″ gap with calk between the plank and trim. Seems to me you would see a lot of calk if that would detract from the job. What’s your experience say? Thanks, Don
Good choice. better than wood which rots, chips, splits, warps, cracks, oh don't get me started.
I prefer wood siding, but hardi type stuff is better than vinyl, aluminum, steel, hardboard, and plywood. Yes, you will get very good at caulking. No big deal. If you use wood, you caulk. If you use vinyl, you use J-Channel, and the worst caulker around can make it look better than that junk.
The stain covers the caulk just fine. I'm still undecided about the butt joints. I have put them up with very little gap and no caulk, or gapped them and caulked them and really don't have an opinion. But either way, I'll give you a tip that can save your whole job--put a piece of tarpaper, about 4x8" behind the seams, overlapping the course below it but not sticking down in view. That way, if any water gets past the seam it will move harmlessly down over the next course, and it should be obvious not to line seams up on top of each other.
I'll give you one more tip for now and it will save a lot of money: buy the stuff primed, not prefinished.
Thanks, one of the guys at my supplier, Sterling or Wausau Homes, is doing his house and doing the tarpaper thing, too. I wondered if it would show up as a slightly wavy wall at each joint. Will take a look at his house.
My shop won't require a lot of siding so painting is not a problem. Do you prepaint the planks before hanging and why do you say not to use the pre-painted?
I think I'll have to buy a digital camera and post some pictures.
I have a question. Why do you suggest not buying Hardiplank pre-finished? We thought that pre-painted and ready to go up would be best.
pre-painted is fine.. but you are still going to have to caulk and paint ... all the joints should be caulked and all the end butts against the trim should be caulked..
after it's caulked, you have to wipe the excess off, clean the adjacent surface and let it cure to the rcommended skin, then paint..
now your fibercement will have two coats ( the factory finish ) and the areas next to the caulk joints... but the caulk itself will only have one...and it will appear splotchy.. so you will probably recoat the entire exposed surface... but again... the clapboard will have two... and the caulk will have one... not the best situation..
so... i would probably choose to install a primed product and field finish with two coats on everything..
here's a pic. of a typical joint with the aluminum spline flash... this is 6.5" Certainteed laid with a 4" exposure...Mike Smith Rhode Island : Design / Build / Repair / Restore
where do you find those spline flashings? i,ve never seen them for sale anywhere thanks larry
we make them up out of coil stockMike Smith Rhode Island : Design / Build / Repair / Restore
Is the spline loose or do you use some type of adhesive?
the two pieces of fibercement clamp it.... and the caulk joint will glue it in place.... the spline also serves as a backer for the caulkMike Smith Rhode Island : Design / Build / Repair / Restore
does harde say to use the spline?
sure looks good
i have no idea what hardie says.... i use Certainteed.... i'll look it up.. but wether they do or not , we'll still use the flashing at the joint...Mike Smith Rhode Island : Design / Build / Repair / Restore
Wow. Someone in the field going above and beyond. I wouldn't look for this any time soon in the manuf. field guides. You'd create another line on an inspectors checklist and make a lot of contractors with hammers and saws mad.
ha... do i have your correct email ?
i've been sending out the details.. so far we've got positive response from everyone at Pete's except you and gaby.. and a host of many others who are dying to meet the other mad dog...
see the fest folder.. RhodeFest accomodations .. how does Aug . 12th - 15th sound ? Mike Smith Rhode Island : Design / Build / Repair / Restore
That's a great backflashing detail. I'm more than a little pissed you hadn't posted it when I did my own house. EliphIno!
thanks............ i guessMike Smith Rhode Island : Design / Build / Repair / Restore
Thanks Mike. I'm with haveasafeday... nice detail. Consider it stolen and inserted in my detail drawings and specs. :-)>
I'm trying to remember the last time I read one of your posts like that one that I didn't learn something. This board rocks!!! Ah-pree-shate-cha!Kevin Halliburton
"I believe that architecture is a pragmatic art. To become art it must be built on a foundation of necessity." - I.M. Pei -
i checked thru my Certainteed manual... couldn't find a reference... saw that detail someplace though.. so we just adopted it....Mike Smith Rhode Island : Design / Build / Repair / Restore
very nice new detail many thanks John
Once upon a time ,they used heavy felt paper strips on the back of wood joints and on the joints of the asbestous siding. I like the al. flashing detail ,much better than felt.
I make my guy use 30# felt pieces at the joints of cedar claps, in doing a similar detail with wood siding. I recall seeing it in FHB many moons ago.
Thank you for your info. I'm not sure how experienced our builder is with this tipe of product. He seems good at the rest of the stuff.. so I'm creating a information/idea file for him. I suspect he will roll his eyes-- but maybe it will help.
Do you absolutely have to paint over the caulked joints if you can get a reasonably good match between colours of siding and caulking? Glad to find this discussion as we plan to put fibercement siding on our house, hopefully this coming year. We don't relish the idea of painting our 2 storey house, so were considering choosing one of the prefinished colours. I'd also be curious to know what most of you are using to cut the product with - the article in FHB recommended shears, but I don't have those, and since the job will likely get done over a "month of Sundays", renting isn't really practical. I do have a good circ saw with diamond blade - would a good mask together with nearby Shopvac make that tolerable? Or maybe a jigsaw is better?
By the way, love the tip about the aluminum joint backer strips - great idea! You could probably make up enough for a house from one or two pcs of alum. fascia, if buying a roll isn't practical.
if you don't paint over the caulk . even with a perfect color match, you will get a different sheen..
also.. i personally think that the paint seals the edge of the caulk and helps to prevent seperation..
and.. if you look back over these threads and posts.. most who used the pre-finished siding still recommended recoating.. so maybe you save ONE field coat
naturally, all of this is somewhat subjective.. and what is acceptable to one may not be acceptabel to someone elseMike Smith Rhode Island : Design / Build / Repair / Restore
Sheesh, guess I should have tacked on my smiley face collection :-)
Also, every house I've seen that had true prepainted sideing, ended up being painted again. Just being on a job site, handled and marked for cutting, passed up 20' in the air and then whacked with hammers...or the big "Hey?!?!?" on the last house was "Hey, that yellow caulk doesn't match the siding!" Okaaay....
In addition to what Mike said, the pre painted siding is a waste of money because you'll end up painting it again anyway, and when you try to match the stain color, it will be different, so touching up doesn't work very well.
When you handle it, or run a saw across it, or do any of many other things with it, each time you'll scratch or fuzz the surface--and it just doesn't touch up well enough to look good.
I paid 25% more for having it prestained than primed. Did two houses that way, and I don't think it was wise.
Don't put the stuff tight to anythng,ie, to itself or trim. It will expand and bow. Other than that, it'll lower your fire insurance and paint up better than an Earl Schieb job. Good stuff.
follow the instructions.. leave the caulk joint.. use a good quality caulkMike Smith Rhode Island : Design / Build / Repair / Restore
Do you think the siding shrinks and swells, or expands and contracts?
I think it is a heat thing. If you put siding up on a hot day, and it has seen a fair amount of sun, it may be prudent not to leave much of a gap at the butts. If cold, then leave close to an eighth. But if I'm using smaller pieces, I make smaller gaps, figuring it can't move as far. I'd like to think that the smaller the gap the better.
Anyway, it's not going to move like vinyl, if it did the nails would gradually hog out the hole and it would fall off the house, or they would make it with slots and force you to overlap it by what, 3" or more...no thanks for that extra weight.
dawg.. the way my painter 'splained it to me..
a crack is an unpaintable surface.. any crack..
modern flexible caulks span the cracks and create a paintable surface..we prime and caulk every paintable surface and make sure all of our joints are caukable..
here's a 1680 Cape we did with Certainteed Fibercement last fall.... we primed and caulked.. the Owner did the finish... every casing /trim has a caulked gap in this picture..Mike Smith Rhode Island : Design / Build / Repair / Restore
there was a good article a while back in FH about hardi, one of the tips said to caulk the seam, then take a putty knife and pull it down the joint following the grain, and bead at the bottom (if present) It makes the joint all but dissappear under paint. good stuff.
Get a good respirator and a blade made for the stuff. The dust is bad news. Justus Koshiol
Running Pug Construction
Just received 560 12' sticks of prefinished Hardiplank today. We'll start hanging sometime next week. I'll post some pix as we move along. I picked the Monterey Grey, which looks very nice, but somehow I failed to notice that the two houses to either direction next door are all greyish. Whoops - I'm feeling stupid. Anyway, we'll be following manufacturers directions for installation (nail with Hardinails in Hitachi siding nailer, gap and caulk, etc.). I was hoping to use the color-matched caluk but it is totally unavailable from anyone - Hardi doesn't even know who manufactures or sells it, though it appears in their literature! Any ideas where to get it? It would sure save a lot of touch up painting at every joint!
I've always heard that our local paint store can color caulking, sooo, I would suggest a few phone calls to yours. I've always had good luck with the color selection of store bought caulking. A suggestion, buy a few small masonry bits for predrilling at the ends of the FCB. Be safe out there Jim J
I BELIEVE the OSI Quad Sealant "# 301 Clay" is close to the Hardi grey.
That must be one big house !!!
As I've been in a habit of asking clients lately, " well, we can check with the crowd, standing at the curb", then Don, I look towards the street, and whalla. My experience, keep the structure plumb/ square, clean lines, that is what the crowd at the curb will see, and ya gotta have a good clean paint job, to match the good clean building job. I would follow manufacter's instructions, as a rule they have a bundle of money and time invested in any written instructions, by people way smarter than me. Jim J
Couple folks have posted info about the Hardi siding itself expanding/contracting with weather/temp. I'm pretty certain that the stuff is dimensionally stable. It won't move. You don't want to butt it up right next to wood trim, because that wood needs room to move with the seasons. If there's no spacing between the moving wood and the immovable Hardi, that trim will push itself away, possibly popping it's nails.