davinci

an installer i spoke with today says when he does a complete tear off and the plywood(sheathing) is in good shape he does'nt use insulation board,only tyvek. he only uses insulation board when going over existing siding. he also ALWAYS uses tyvek whther its a teat off or over esisting siding. do you guys do the same?

dougchips

Take a free siding training class instead of talking to people that go over existing siding. A good class will spend some time talking about perms/perm ratings, it's sort of an important thing to understand.

Patrick

why dont you go spend some time with a competent installer?

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Originally Posted by Celtic
Like I said...I'm sure you are very good at what you do ~ whatever that is and where ever it happens.

davinci

seriously Pat, what is your opinion? and yes, i'll heed your advise.

dougchips

But you will not attend a training class to learn how to install a product to industry standards? I still go to classes after installing the same stuff for the last 15 years.

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To get the best replacement windows, or sun rooms contact the replacement windows experts at FHI Vinyl Window Company.

kirbymurphy

I've seen some really ugly, wavy walls even when the sider did use foam board. Can't imagine not using foam board or foam-backed siding. The worst of course are the long side walls when viewed from the street.

davinci

ok, so they also use insulation board to make the plywood appear more even(less wavey)?

JHD

That's a fair assertion. The primary advantage to foam insulation is to provide a rigid backing. The actual R value gained is not that significant.

As for foam-backed siding, yes it is a great product. But you'd better know what you're doing. There is almost no room for error.

I just finished a job using Heartland Cedarmax. 3 gables, 2 rakes, 3 dormers (one that was 12' tall, with an arched window.) Every cut on this house was on a pitch. It was about all I wanted to see of that stuff for a while.

davinci

i don't get it. if the plywood is wavey, won't the insulation follow the contour of the plywood?

rayh78

Yes
there is no benefit for the foam board over a flat surface like plywood.

JHD

It also depends on the siding. A lot of premium panels can go a log way in hiding the inevitable waviness of plywood and OSB.

brutis

the only way as it says in the VSI , vinyl siding institute, the society of the plastics industry inc,
just start shiming straight line it every 2 ft. all the way horz. up the wall, use 3 in, nails or screws hold string a set out from wall like maybe 1 in, or 1 1/2 out so theres room to work behind it and just shim, shim and shim , with diferant thicknesses of wood, vertical up and down wall, shim every 2 ft. or what ever your going to nail siding spaceing , here we use 1/4 in lathe and just double it or triple it, what ever is nessary , and at least you can get it fairly straight with in a 1/4 in or so ,

you should exsplain to customer why the price is so much higher to do this, lol , or just do it and be sure to show them before and after, make them see the old surface wave and new shimmed siding straight

Remodel Bud

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enforcer

personally i like to use 1/2 foam board over the substrate along with a house wrap;although just using tyvek would be fine as long as the surface is flat.when going over existing siding(i hate to do it), i just use foam board,no tyvek wrap(why would we need to).

clapboard

Install something real. Otherwise, you are playing with yourself.