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Best source for long screws?

davidmeiland | Posted in General Questions on

I’m sure this has been asked and answered before. I need screws in the ~8″ range to assemble a rigid insulation/wood sandwich, specifically 5/8″ CDX over 6″ rigid over 1-1/2″ car decking over 4×8 rafters. Many of the screws will land in the 4×8, so could be 8″+, but some will need to land only in the car decking without coming through, and something like 7-1/2″ would be ideal. Haven’t look anywhere yet, but I know folks here have the answers already.

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  1. GBA Editor
    Martin Holladay | | #1

    Some suppliers of long screws include:
    Best Materials — Dekfast 6-inch roofing screws and Dekfast 9-inch roofing screws
    Wind-Lock (a source of long screws and plastic hold-down buttons)
    FastenMaster (a source of screws up to 18 inches long)

    Dan Kolbert posted this a while ago: "Look into SIPs screws - various manufacturers, somewhat cheaper, wider variety of sizes, and the flat-ish heads work better for this type of application. Any commercial roofer should know where to get them, or there are plenty of online sources."

  2. Expert Member
  3. gusfhb | | #3

    abc roofing, nationwide chain, bucket of 1000

  4. Adam Emter - Zone 7a | | #4

    I ordered some 7" screws for my rigid foam project from these folks: Good product and the prices seemed good. Got my 10" timber screws from my local Menards store. They were quite a bit cheaper than the FastenMaster variation and seemed every bit as good.

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