Can’t find any specifics on installing fanfold siding underlay (blue foam). Want to put vinyl on old ranch, over approx 8″ exposure wood siding.
Do I lap horizontal joint, or butt? Try to land the joint on a high spot to keep flat, or does it need to be shimmed/furred at joint? I looked at all product sites I could find, but have not found any thing except VERY general instructions.
Any help with this greatly appreciated..I gotta do this myself, and city is up my rear to do something with it, NOW.
Thanks, all in advance.
Brian
Replies
Check your perm rating before buying foam fan fold the higher the number the better. At 8" every 6th course should be at 48" just right for 48" fanfold,taping all seams helps to cut down on infiltration, just remember fanfold is really just a leveler but with double 4"if you do your layout right you can end up nailing on only the high spots.
Thanks for the advice, sorry for the delay, I have been runnng like a crazy man and then a holiday week!
Exposure on siding is actually more than 8" , but I really wasn't going to try to layout the siding to try to hit the high spots, I just wanted to find out how I needed to nail/staple the fanfold foam to the old siding, in order to get that leveling effect.
I,ve never seen this material installed before. I know it is often done, but I never seem to go by one at that stage. Usually up & gone so quickly. Do you nail / staple the fanfold to high spots and free float seams if they don't line up witha high spot, or plan to put the seam at high point? (As the wall is about 9' I'm gonna be cutting at least one narrow strip? Do I lap the seam to shed water? As to the perm rating, the selection I have access to is limited to what the home center carries. I would rather I did not have to use this material at all, but I can't find any alternatives, other than stripping off al the existing, (BIG job, I should think). I toyed with the idea of putting 1/4" exterior plywood or OSB type material on instead, as I would prefer the walls to breathe. (some of the walls insulated, others not, etc , hodgepodge).
Please any thoughts, or elaborations are welcomed enthusiastically!
Thanks again!
Brian
I nail on the high spots. Start with a fold on a corner and unfold, 2 nails per fold is fine,when you install siding you will be nailing every 8"vert & 16" horz, butt and tape all seams, packing tape in a tape gun is real nice, overlay and double cut small areas for a tight fit. If you go to a siding distributor you should be able to get Pactiv GREEN GUARD its perforated and comes in 1/4" & 3/8" DON'T use standard blue board as it will trap any moisture that escapes the interior vapor barrier. Stripping claps doesn't take that long, it's the clean up and disposal that's the killer but it is my prefered method.
Finally got back here... Thanks, much! Since I posted last, they have begun to fanfold and side the house next door, so I finally got to look at the job up close & personal.
I really appreciate the asssist, nobody here likes to talk about vinyl ( HA ). I have googled the whole world, looking.
I think I've got it!
Brian