I'm close to having to replace the asphalt shingles on my roof. You can see dips in some areas of my roof because the builder put 1/2" plywood sheathing over trusses that are 24" on center. Question, what would do a better job at camouflaging the dips, lighter colored shingles or darker colored shingle?

Slate. A darker grey, between a 14% grey and charcoal. Like the upper right in the image.

Too dark and you will see the dips almost as much as a light color.

The "dimensional" (look like 3D) will also help break up the visual of the defects.





Better image of the effect the dimensional shingles.

^^^^^^ also known as architectural shingles or 6 tab shingles. As long as you have enough pitch.

Here's the colors available to me if I go with the contractor that did my neighbors house.

https://www.certainteed.com/re...g/products/landmark/

hmmm, dips in the sheeting. Do not like the sound of that. I assume you are going to lay the new shingles over the old ones verus doing a tear off?
Are dips in roofs common in your area.?

I would NEVER put on a new roof without tearing off the felt and inspecting every inch of decking. I would use architechtural shingles only. Make sure every shingle is nailed properly with the requisite number of nails. As with most things, it is all in the installation. I can pretty much guarantee you have some bad decking that needs replacing.

Your contractor may be required to update your plywood thickness.

I had mine done last year and they couldn’t, by code, put a new roof on 1/2”.

I was ok as I had 5/8, but neighbor had to pay for all new plywood.

Are you saying your going to replace the shingles but not fix the plywood?

Its going to suck but pay the money to have the plywood replaced. A few years back the roofers told me plywood was replaced at $100 a sheet.

15/32 chip board -almost 1/2" is common in my area - not a lot of snow. It is "spongy" to walk on but no obvious dips. If it looks wavy from the front between rafters, its not good. Check your attic for dark spots (mold) and ensure there is adequate ventilation.

A complete tear off is the way to go like others have said.
A second layer of shingles is just gonna put more weight on those dips.
And getting to see your wood is going to tell you a lot.
Wood is expensive now but if you’re staying in this house it’s worth it to make it right.

I would also make sure that the h clips were or are used between sheets.

Thicker plywood would get rid of the dips. And I’m thinking adding blocking between the 24” trusses would help negate the dipping sheeting.

I used 5/8” CDX plywood with the “H” clips 31 years ago. CDX does have a tendency to sag a little. I’m hoping to install standing seam next year. I haven’t had any leaks, so hoping all is good underneath.

I see it on brand new homes around here. It's possible that there is some sag causing it, but it an also simply be slightly uneven trusses that make the roof look wavy.

As was previously mentioned, a multi colored architectural shingle will break up the appearance of the roof and is more likely to make it less noticeable.

24” OC truss spacing is normal throughout the country and unless you have a very high snow load using 7/16” OSB is SOP and code approved.

If you really have dips there may be other things going on…

quote:

Originally posted by a1abdj:
I see it on brand new homes around here. It's possible that there is some sag causing it, but it an also simply be slightly uneven trusses that make the roof look wavy.

As was previously mentioned, a multi colored architectural shingle will break up the appearance of the roof and is more likely to make it less noticeable.

Yep. Mostly likely the trusses/rafters as wood used over the past 30 years is sourced from faster growth/younger trees, and OSB instead of plywood, lend themselves to the problem of the waves.

When I was building, 5/8" plywood and blocking between trusses/rafters and in some cases would kerf a rafter that was off and sister another to it.

Had the carpenters "string" the rafters to make sure they were true and that the decking would be flat. It added some time and a few hundred to the cost of the roof compared to others, but your going to be seeing that roof for a very long time, and your finished houses sold your next builds.

quote:

Originally posted by P229 357SIG Man:
Question, what would do a better job at camouflaging the dips, lighter colored shingles or darker colored shingle?

Neither. Dips in an asphalt shingle roof are going to hold moisture longer than the flat surfaces which will be obvious to anyone looking at the roof. Dependent on how big and complex your house is, and what sort of attic access you have, a solution would be to fix the problem by installing cross bracing between the trusses before the new roof goes on. That of course assumes the sheathing is in good shape. The best solution in my opinion would be to re-sheath the entire roof with thicker material before applying the new covering.

Good points made by all. I called the roofer today and he's coming back out to take another look at it.