Average wood needing replacement on new roof?

Hi all,

We are in the process of getting a new roof and were wondering what the average amount of rotten/damaged wood needing replacement is during the process. We negotiated with one roof to include 20 linear feet in his price (our roof’s about 1500 sf). But 20 feet’s not a lot, right? After 20 feet, we would be charged $4 per 1" by 6" linear foot. The roofer claims most customers never need more than 40 feet replaced

The roofer did not walk around on the roof, but another roofer told us the roof seems in decent shape (we are mostly replacing to vent, and it’s not worth it to retrofit when we need a new one in about 5 years anyway).

Any insight on typical replacement amounts?

Its pure speculation. There are WAY too many factors, and every single roof is totally different.

If he didn’t even walk the roof, I wouldn’t hire him. Plain and simple.

Depends on a lot of things. With no pictures or walking on the roof it is impossible to say. One of the bigger determining factors in my experience is the pitch of the roof. The flatter the roof the more leaks it will eventually develop.

theres NO way to be exact for sure until someone tears it off, and if he didnt walk the roof he defianty cant even guestimate how much it will take. We charge $35 for a 4x8 whole after the 1st one take pictures for the homeowner to see.

35$ a sheet!!!thats depressing. how are you making money? and 9 times out of 10 the wood rot in in a SOB area that it takes even longer to replace. maybe $35 a sheet if were resheeting the whole deck.

Did he go into the attic? Usually a look in the attic,and a stroll on the roof will give an idea…
If it is too steep to walk,it is 1 thing, but if it is walkable,and he did not get on it, In My honest opinion, he did not earn the job.
I am not the cheapest guy, but I inc. 3 pcs 1/2 ply., if it is plank, I include 1 pcs 3/4 cdx.
Age of home,and lack of attic vent… will contribute to rot.

35$ a sheet!!!thats depressing. how are you making money? [/quote]

i charge $45/sheet

$8 a sheet for wood, 10 minutes to change it out.

looks like profit to me.

$8 a sheet. that must OSB. for 1/2" 4ply plywood its $16 a sheet. so yah, theres no money in there for me.

yea. $8 for OSB. 80% or more of the roofs i get on are OSB.

CDX is only a couple dollars more here. maybe $10 a sheet.

Agape pretty much said it all. its about $8-10 sheet here. and my guys replace within 10-15 minutes. and btw its $35 up to a 4x8 hole whether it be 2x2 or 4x8 I charge the same.

On an average we dont replace any on a roof.

Usually if the roof has 1x decking less than 10 lf

Osb or ply wood, none unless the roof has been leaking. But you would then have a damaged ceiling.

hell go with the 40’.


[quote=“gweedo”]hell go with the 40’.


Only if the roofer wants to give the homeowner an add/deduct price for wood replacement.

Cost of materials to be replaced plus 30% + $50 per hour, to do any sheeting repairs.
This is stated on the contract and discussed at time of signing.

If it is a minor sheeting repair, I will usually just do it at no charge.
Customers are then getting something for free and the cost is minimal to company. Good for referrals.

just my $0.02…(don’t tell the government or they will tax it)


We are $45 per 4x8 sheet for plywood (not OSB). $4 per lineal foot of 1x decking.

If you home has existing plywood or osb type sheathing I wouldn’t expect you would have to replace any. Unless you have had water damage then maybe a board or two and yes $45-$75 per sheet is normal. So maybe $150 best guess. If however you have an older home and the decking is the old 1x6 or 1x8 planks…if there are gaps of greater than 1/2 inch between the boards…you can expect to redeck the entire roof. Average roof size for a residential home is maybe 30Sq or 3000 sq ft. This would require maybe 100 boards…at $50 a sheet you are looking at an additional $5,000.00.

If you can get into your attic you should be able to tell if your decking has large gaps.

thats $8 a square foot :shock: Something doesnt sound right to me.

A sq. of roofing will take 3.3 sheets of 4x8 sheathing. 30 sq x 3.3 would equal 99 sheets. Rounding to 100 sheets for easy math x $50 a sheet is $5,000

Your math is correct Marshall. Sounds like Roof top rip off to me.That guy could retire if it is a full re-deck… :shock: