Recycled Decking Materials + Cool-granule shingles

Sorry if this gets a little long - just want to put some context around the main topic: decking.

40y+ home, 2 layers (1st 3-tab white, 2nd 3-tab dkGreen 20y+), small gable vents, no intakes, disrupted attic insulation & vapor barrier, blackened plywood N side interior, no mold on 2x6 framing (sap droplets - doug-fir).

So that’s what we have, and I figure we tear the whole roof off, decking and all, so everything is done properly and is the same age. There may be some of the roof that’s in relatively good shape, but looking at how dry and delaminated some of the “good” sheets are underneath, I get nervous about putting nice new shingles over decking that hasn’t been vented properly for so many years, for the variety of conditions that creates.

As for the weather surface, if it were up to me, I’d go white standing seam metal, but it looks like it’s not, so I’m looking at laminates like Certainteed ‘Woodscape’ 30year (Birchwood) or GAF/Elk/3m’Cool Colors’40year. Anyone have experience with those? Big price difference?

Trying to reduce heat gain up front, while adding Inhaler vents at the gutters, and Ever-Flo external filter ridge vents. Grace Ice & Waterat all edges (strip @ gable drip), and their TRI-FLEX 30 synthetic underlayment because we may want to blow off the whole roof deck and possibly spray-foam the attic floor, and that entails removing old insulation and mouse droppings (some beforehand), so we’ll be lucky to get all the decking back on in one day, much less shingle it. 8-penny ring-shank nails every 6" for the decking, btw. Caps for the underlayment.

Still haven’t figured out a product for sealing the DWV 2" copper stacks. Is there an enameled stainless steel cap/sleeve/flange product that’s formed to clad the entire pipe? I suppose copper is best if you don’t want lead.

Okay, decking…

Is there a way to quickly remove en-masse the old decking with most of the shingles still on it, so it can be processed on the ground? Big staple-remover type tool that operates under the decking on the framing, perhaps? Quicker and safer, I’d think.

I don’t like the idea of sending so much plywood to the landfill, and I doubt it could all be recycled like the shingle waste. It would be great to divert at least as much material from the landfill as we’re putting in.

OSB is sustainable and engineered for the job, so it’s my backup choice, but what about laminated paperboard? I hear that’s largely post-consumer waste, used on industrial roof jobs, but can it be rated for residential, where do you get it, and what’s it cost?

I saw a product called Homasote Firestall, which is pretty thick heavy stuff. It’s not the same as the other paperboard products, right? It’s recycled, and made in the region. Pricey?

There have been fiberboard products and the like which have proven to be nightmares in exterior applications, so I’m hoping the technology is back on track and we can buy recycled sheathing/decking now.

yes roofus, to long.
shortin it up a bit.
ask questions simply.


Just cut the plywood vertically with a reciprocating saw or circular saw inbetween each rafter. Then you can rock them side to side to remove.
Is shingle waste really recycled? How will you recycle the plywood?


Shingle waste is recycled into paving materials, just like anything (or anyONE?) you want to get rid of! :shock:

Plywood you can’t do anything with, it seems, especially if there’s decay. Mulch might be considered toxic unless there’s a process that addresses the fungus and glue issues. High-temp incineration or gasification might be the only things to do. Plywood or OSB might be pulped into cardboard if it’s in halfway decent shape. Old dried-up roof deck that’s full of nail holes and splinters but otherwise clean might be put through a sander and re-used in less demanding applications. Still looking for companies that do take mixed-condition plywood.


Sorry, yes, it’s a bit much to pick through, so I’ll ask you this: Is 40 years, poor venting and 2 layers enough service life for 1/2" plywood? It’ll have to go another 30+ with new shingles, so now’s the time to decide on patch or replace.

Onsite Beneficial Reuse of Ground Engineered Wood Wastes from Residential Construction
University of Georgia May 2004

Pages 39-40

[quote]Overall, the study indicates mulches with an EWP component should be safe to use onsite. The ground wood waste can be used as a landscaping mulch, for erosion control during construction, or as a substrate for a heavy use area…

Structural engineered wood products comprise about 30% of the wood waste from residential building projects. Because these products are used in all phases of construction it is difficult for builders to segregate them from dimension wood wastes. The results of this study indicate these wood wastes can be beneficially reused onsite during construction rather than going to a landfill.[/quote]

Hmm… They seem to think that the glues in engineered wood don’t pose a problem if you just leave them lying around. We’re told you’re not supposed to burn them in the open because of toxic smoke/ash. Any wood particles that are tilled into the soil are supposed to have nitrogen added because they deplete nitrogen from the soil.

So maybe it would be possible on-site to shred the plywood or OSB from a roof deck tearoff and use it on the property? I’m still concerned about fungal activity, but maybe the soil organisms would compete.

That, plus the shingle recycling info I posted in a new topic, could cut WAY down on disposal fees and landfill use.

as long as it feels good and looks good.
its ready for anothe 30 yrs.