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Fiber Cement Siding advice

Soon, we will have our roof redone and there are several dormers. The roofer will take off the asbestos and fiber cement siding on the sides/walls of the dormers to install new flashing (old Colonial home). Therefore, we have to purchase new packages of fiber cement siding. The match is GAF Weatherside wavy edge, comes in pkgs of 18 pieces about 18" long approx. Roofers will reinstall any good pieces of fiber cement siding and the new. We found there's a lot of waste with the product when we replaced broken ones a few years ago because of all the sharp angles of the dormers, cutting many pieces to fit and they break easy. The whole house has the wavy edge siding.
I'd like some advice on my thoughts...
Maybe, I should find larger fiber cement board siding and forget about dealing with all these little pieces to fit and less waist, maybe less money and less seams for water to penetrate?
Not sure of the cost on that compared to the single siding pieces or what brand types to consider?
And/or...we hate the edge lines on dormers where the siding meets the roof lines because it's not a clean neat edge like with plastic siding; we can see the flashing on all the edge lines and it looks sloppy. We could also get a few of the straight edge fiber cement siding and put that on the last course against the roof lines that might make it look neater? (maybe your suppose to see the flashing a bit so the siding doesn't but up against the roof line, IDK)?
Advice on best place/price to purchase this siding? It's expensive and contractor doesn't supply it so I'm stuck with Home Depot special order and all the extra parts to match in Massachusetts.
Thanks for any advice.

Re: Fiber Cement Siding advice

with the siding dieing into the roofline theres no way around the off cuts. your better off using full lengths for shorter runs, several short peices for a 6 ft run looks terrible and isnt as easy to keep running straight and you have to touch up the ends with touch up paint before it goes on the wall

. hartiplank has the best track record of any of the brands. certainteed has been having all kinds of warrenty issues right across north america with their product, mainly because of the installation method they recommend. in regard to cost i dont know what the 8 1/4 wide harti is going for the 5" harti is $20 per piece locally. have you tried a siding supplier in your area, they can usually get it for you at a better price than the big box stores as its not a special order item for them, or try a lumber yard that deals mainly to contractors. also they will get it in 100 x faster than hd ever will. hd deals in stuff they sell off the rack not custom orders, part of the reason their contractor sales only account for about 5% of their total sales

now, on the issue of the flashing, the siding has to be kept up 2" off of the roof so it doesnt soak up rain water running down it. otherwise it will swell up and flake rendering it useless. one way to make the silver step flashing less noticable is to bend up black or dark grey aluminum as a z flashing which goes over the step flashing to make it less noticable. or another option is to make a trim piece out of azec which will sit down close to the roof and then the siding starts on top of that, wood wont do because it also has to stay 2" up off the roof

Re: Fiber Cement Siding advice

If you have a steep roof (10/12 or greater) I really like running the siding on the slope. There's always less chance this way of damaging the siding; only the first course is in jeopardy of water damage.
And what he said /\ about the 2" space above the shingles; absolutely necessary with cement board siding. And consider using plain or beaded lap siding on the dormers; it has much precedent to treat them as separate entities.

Re: Fiber Cement Siding advice

Thank you both for your response. I understand a lot of what you wrote.
We have 5 tiny dormers; no more than 3 feet from the longest part of roof line and about 4' tall walls near the window edge.
Very steep A framed roof.
The Hardiplank sounds much more expensive and smaller in width but I will check it out and adding the composite trim $$$. But maybe the lengths of the boards are longer. I tried before to order from a Contractor's supply house but they wouldn't let me. I'll check lumber yards. Home Depot does custom order and takes about 2 weeks. I will still need to buy some packages for the front facing corners of the dormers where the roofers will remove some to install new flashing.
If we make the change to the straight boards (I'm assuming they don't have wavy edge to match what we have)on the dormers; I hope it doesn't stick out like a sore thumb by not matching the rest of the house. Has to look good.
P.S. I hope Certainteed isn't having problems with their roof shingles because we are going to install their Architectural grade? Please, let me know.

Re: Fiber Cement Siding advice

I was just thinking about the winter and how the snow packs into the sides of many dormers and sits there all winter long and eventually melts slowly along the siding walls and roof lines. Not good for any siding that swells from water.

Re: Fiber Cement Siding advice

An update. Got new roof installed.
Looked at Fiber Cement Plank Siding (HardiPlank) and found best prices on Lowes.com or Home Depot.com about $10 a board a few weeks ago; 8"w x 12 or 16' long.
Looked at 70 homes with dormers and found that 99% used the same siding on the dormers as the main house for a continous look, therefore, we went with the wavy edge fiber cement siding shingles by GAF and new corner beads. Looks really good all new and nice clean edges.
Roof line where siding meets roof looks much better with the new shingles and less flashing exposed. Wanted the pvc/composit trim on that line to cover the metal flashing (on the outside edge over the bottom of the siding panels) but roofers and siding company does not recommend it at all. Possible water penetration and prevents the water run-off. So,sometimes what we think will look good (like nice neat dormer lines on vinly sided homes) is not the best for the house with other siding.
PS. If anyone is looking to replace asbestos broken siding panels we found best match replacement options on the GAF website and directions. Can by same siding at Home Depot.com with free ship options for less $. More accessories offered at the GAF site.
Also, used roofer from Angiels list with high ratings.
Saw another roof being done wrong same day as ours was done. Scary.
Thanks for all your advice.

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