Cedar roof: treatment/preservation
Cedar roof: treatment/preservation
4 years ago I had the original (22 yo) cedar roof on the house I moved into replaced with a new cedar shakes roof. It was very expensive $55K job but the association does not allow asphalt shingles (which would be my 1st choice) and the seller paid most of the cost. Would be even pricier job now--in fact, the cost of cedar has gone up so much that other houses in the neighborhood appear to install DaVinci system artificial "cedar" roofs.
I am getting the ads for roof treatment/preservation from both the original installer and other parties and wondering if it is a good idea to have the roof treated. Does it truly prolong the life of the cedar roof? Is it a good investment? I am sure it is not cheap, as the ad from original installer promises "$500 off" but I did not ask for any quotes. My roof is in mostly open area with just a few spots that are not exposed to the sun or have tree branches right above it.
If you happened to have an educated opinion or knowledge of the subject, or if you did the treatment for your own cedar shakes roof, I would appreciate any feedback (was it expensive, would you do it again, are you in favor of some particular treatment method or chemical, etc)
Thanks!
I am getting the ads for roof treatment/preservation from both the original installer and other parties and wondering if it is a good idea to have the roof treated. Does it truly prolong the life of the cedar roof? Is it a good investment? I am sure it is not cheap, as the ad from original installer promises "$500 off" but I did not ask for any quotes. My roof is in mostly open area with just a few spots that are not exposed to the sun or have tree branches right above it.
If you happened to have an educated opinion or knowledge of the subject, or if you did the treatment for your own cedar shakes roof, I would appreciate any feedback (was it expensive, would you do it again, are you in favor of some particular treatment method or chemical, etc)
Thanks!
Re: Cedar roof: treatment/preservation
No one had to deal with it, folks? Surprising, cedar roofs are not that rare.
Re: Cedar roof: treatment/preservation
You’ve stumped the bogleheads. I don’t know if I’ve ever seen that. There should be a term or a prize for such a thing.
I’m sure it’s a regional thing. I’ve honestly never seen a cedar roof that I can recall. Certainly seen cedar siding, but never a roof.
If the idea here is that mold or fungus will reduce the life of the shingle, I might investigate “wet and forget” as a preventative DIY measure. I saw pictures in the web from a guy in NC. He started spraying his roof, then ran out if stuff or something. He never finished. So the pictures are of his roof after one year. Part of it looks like hit garbage, and the other part looks almost new.
I’m sure it’s a regional thing. I’ve honestly never seen a cedar roof that I can recall. Certainly seen cedar siding, but never a roof.
If the idea here is that mold or fungus will reduce the life of the shingle, I might investigate “wet and forget” as a preventative DIY measure. I saw pictures in the web from a guy in NC. He started spraying his roof, then ran out if stuff or something. He never finished. So the pictures are of his roof after one year. Part of it looks like hit garbage, and the other part looks almost new.
- FrugalInvestor
- Posts: 6213
- Joined: Thu Nov 06, 2008 11:20 pm
Re: Cedar roof: treatment/preservation
I used to have a cedar roof but wasn't in the house long enough that I needed to worry about the roof. If I'd been it it longer I definitely would have put some sort of preservative on it periodically. I can't recommend a specific product but I think you may find the following website to be helpful in learning what to look for....
https://www.cedarbureau.org/literature- ... nance-faq/
Cedar roofs generally aren't what they used to be because the large 'old growth' trees are not as available (and probably shouldn't be). Cedar taken from younger and smaller 'second growth' trees doesn't contain nearly as much of the natural preservatives. For this reason most cedar shingles and shakes purchased today won't last as long without man-made preservatives being applied, and maybe not even then.
This may be an opportune time for you to petition your HOA to change your CC&Rs.
https://www.cedarbureau.org/literature- ... nance-faq/
Cedar roofs generally aren't what they used to be because the large 'old growth' trees are not as available (and probably shouldn't be). Cedar taken from younger and smaller 'second growth' trees doesn't contain nearly as much of the natural preservatives. For this reason most cedar shingles and shakes purchased today won't last as long without man-made preservatives being applied, and maybe not even then.
This may be an opportune time for you to petition your HOA to change your CC&Rs.
Have a plan, stay the course and simplify. Then ignore the noise!
Re: Cedar roof: treatment/preservation
Cedar roofs are not uncommon in New England. Mostly on historic and high end buildings. They need to breathe which is why solid wood sheathing under a cedar roof is not a good idea; most use "nailers" (1X4 boards) spaced on centers equal to the shingle exposure. And cedar shingles usually require at least an 1/8" gap between shingles as they expand when wet. I've noticed driving around that copper flashing on a chimney usually creates a lighter color shingle when the flashing gets wet and drips on it. I've also seen roofs with zinc strips running across the roof on either side of the ridge which has a similar effect. Don't know if that prolongs shingle life. (I should probably be watching the road more and not admiring roofs)
- FrugalInvestor
- Posts: 6213
- Joined: Thu Nov 06, 2008 11:20 pm
Re: Cedar roof: treatment/preservation
The zinc strips are used to keep moss, algea and other organic stuff from growing on cedar roofs and they work pretty well. But the cedar still needs to have water resistance so it doesn't rot. If the natural oils in the wood doesn't provide that resistance or when it wears out then man made concoctions are necessary to prolong the life of the roof.pshonore wrote: ↑Tue Jun 28, 2022 7:51 pm Cedar roofs are not uncommon in New England. Mostly on historic and high end buildings. They need to breathe which is why solid wood sheathing under a cedar roof is not a good idea; most use "nailers" (1X4 boards) spaced on centers equal to the shingle exposure. And cedar shingles usually require at least an 1/8" gap between shingles as they expand when wet. I've noticed driving around that copper flashing on a chimney usually creates a lighter color shingle when the flashing gets wet and drips on it. I've also seen roofs with zinc strips running across the roof on either side of the ridge which has a similar effect. Don't know if that prolongs shingle life. (I should probably be watching the road more and not admiring roofs)
Have a plan, stay the course and simplify. Then ignore the noise!
Re: Cedar roof: treatment/preservation
Yes, the "stumped the bogleheads" prize would be nice! You should drive through our subdivision, there are so many cedar roofs, they would leave lifetime of impressions on you
Re: Cedar roof: treatment/preservation
Thank you for the link! Yes, I heard the same thing about young trees being used, one cannot count on more than 20 year with cedar roofs now, 25 if they are lucky. But perhaps treatment makes a difference. And unfortunately they installed only 1/2'' thick cedar. I wish it was 3/4 which hold up much better, but the cost was prohibitive for the seller.FrugalInvestor wrote: ↑Tue Jun 28, 2022 7:33 pm Cedar roofs generally aren't what they used to be because the large 'old growth' trees are not as available (and probably shouldn't be). Cedar taken from younger and smaller 'second growth' trees doesn't contain nearly as much of the natural preservatives. For this reason most cedar shingles and shakes purchased today won't last as long without man-made preservatives being applied, and maybe not even then.
This may be an opportune time for you to petition your HOA to change your CC&Rs.
Re: Cedar roof: treatment/preservation
I am sure they did it correctly, that was a job done by large company that works in our area on cedar roofs installations exclusively (Shake Guys). A crew of 5 people worked about 10 days on it. But sun, rain, and freeze/thaw cycle will do its job. The original roof, that I am sure was not treated since the place was rented out most of the years, lasted only 22 years and the inspector said it was barely holding up still.pshonore wrote: ↑Tue Jun 28, 2022 7:51 pm Cedar roofs are not uncommon in New England. Mostly on historic and high end buildings. They need to breathe which is why solid wood sheathing under a cedar roof is not a good idea; most use "nailers" (1X4 boards) spaced on centers equal to the shingle exposure. And cedar shingles usually require at least an 1/8" gap between shingles as they expand when wet. I've noticed driving around that copper flashing on a chimney usually creates a lighter color shingle when the flashing gets wet and drips on it. I've also seen roofs with zinc strips running across the roof on either side of the ridge which has a similar effect. Don't know if that prolongs shingle life. (I should probably be watching the road more and not admiring roofs)
- FrugalInvestor
- Posts: 6213
- Joined: Thu Nov 06, 2008 11:20 pm
Re: Cedar roof: treatment/preservation
Looking up into your attic will likely quickly tell you if wood strips or solid sheathing is used under the shingles/shakes.serbeer wrote: ↑Tue Jun 28, 2022 10:16 pmI am sure they did it correctly, that was a job done by large company that works in our area on cedar roofs installations exclusively (Shake Guys). A crew of 5 people worked about 10 days on it. But sun, rain, and freeze/thaw cycle will do its job. The original roof, that I am sure was not treated since the place was rented out most of the years, lasted only 22 years and the inspector said it was barely holding up still.pshonore wrote: ↑Tue Jun 28, 2022 7:51 pm Cedar roofs are not uncommon in New England. Mostly on historic and high end buildings. They need to breathe which is why solid wood sheathing under a cedar roof is not a good idea; most use "nailers" (1X4 boards) spaced on centers equal to the shingle exposure. And cedar shingles usually require at least an 1/8" gap between shingles as they expand when wet. I've noticed driving around that copper flashing on a chimney usually creates a lighter color shingle when the flashing gets wet and drips on it. I've also seen roofs with zinc strips running across the roof on either side of the ridge which has a similar effect. Don't know if that prolongs shingle life. (I should probably be watching the road more and not admiring roofs)
Have a plan, stay the course and simplify. Then ignore the noise!
Re: Cedar roof: treatment/preservation
It may be worse than that.FrugalInvestor wrote: ↑Tue Jun 28, 2022 7:33 pm Cedar roofs generally aren't what they used to be because the large 'old growth' trees are not as available (and probably shouldn't be). Cedar taken from younger and smaller 'second growth' trees doesn't contain nearly as much of the natural preservatives. For this reason most cedar shingles and shakes purchased today won't last as long without man-made preservatives being applied, and maybe not even then.
20+ years ago I had a house with a cedar roof and when I was dealing with it my understanding was that the cedar that was available even 20+ years ago was from an entirely different inferior species of cedar than the type of cedar that was used 100 years ago.
I ended up having major repair work done instead of replacing the roof because a replacement would have been so expensive. As I recall that should have extended the roof life for another 5 to 10 years since I had the better old cedar.
Even putting an asphalt shingle roof on the house would have been expensive since that required the underlying structure and supports to be modified.
With it being that long ago my recollection is a bit hazy but as I recall the roofer I used did not like the cedar roof treatments because the people walking on the roof every year to spray the treatments tended to damage the cedar roof by walking around on it. I never used any roof treatments.
I ended up getting transferred and sold the house before anything else needed to be done with the roof.
I would suggest calling the roofer who put on the roof to see what they say you should do. Be sure to also ask if there are any warranty requirements for treating the roof, or not.
Re: Cedar roof: treatment/preservation
Interesting! Thank you.Watty wrote: ↑Tue Jun 28, 2022 11:03 pm With it being that long ago my recollection is a bit hazy but as I recall the roofer I used did not like the cedar roof treatments because the people walking on the roof every year to spray the treatments tended to damage the cedar roof by walking around on it. I never used any roof treatments.
Re: Cedar roof: treatment/preservation
They used to be pretty common in Texas (30 years ago) but they were deemed a fire hazard and are rare now. If one house had a fire, burning embers would land on the neighbors house and cause their house to catch on fire
- lthenderson
- Posts: 8499
- Joined: Tue Feb 21, 2012 11:43 am
- Location: Iowa
Re: Cedar roof: treatment/preservation
Probably the biggest factor in cedar longevity is what kind of cedar it is. The known superior cedar for shake roofs is edge grain western red cedar or Alaskan yellow cedar. If they are flat grain or of other cedar types, they will degrade much faster. I work with wood quite often and use a lot of cedar. Although it doesn't rot out like other woods, it will bleach and become brittle as the oil in it dissipates so regular application of oil will most definitely help lengthen its lifetime and preserve the good looks longer. Whether or not it is worth it or will add a significant amount of time depends on the pricing. Assuming a 25 year lifetime, you are essentially depreciating out your roof to the tune of $2200/year. I would get a quote on the actual cost (non-discounted) of treatment over the lifetime of the roof and their estimate of how long it should last with treatment and do the math. Like others mentioned above, especially if the installation was done correctly, frequently walking on cedar shake roofs do a lot of damage. Can they apply the treatment from the ground or bucket lift or do they have to walk on the roof?
-
- Posts: 1830
- Joined: Tue Feb 07, 2017 8:08 am
Re: Cedar roof: treatment/preservation
Another factor is the pitch of the roof. Shallower pitch = more time in contact with water = shorter life.
From what I've seen the main spirit of cedar use is that it has natural preservatives, so you leave it alone.
I don't think copper would add much life to it, because I've run an experiment: I kept copper pressure treated pine fence pickets in a horizontal position with full exposure to the elements for 5 years (snowy long winters, warm summers). This year, some of the pickets have started to break. They've lost all their color and the grain is deep fissures.
From what I've seen the main spirit of cedar use is that it has natural preservatives, so you leave it alone.
I don't think copper would add much life to it, because I've run an experiment: I kept copper pressure treated pine fence pickets in a horizontal position with full exposure to the elements for 5 years (snowy long winters, warm summers). This year, some of the pickets have started to break. They've lost all their color and the grain is deep fissures.
45% Total Stock Market | 52% Consumer Staples | 3% Short Term Reserves
Re: Cedar roof: treatment/preservation
Very good advise!lthenderson wrote: ↑Wed Jun 29, 2022 5:32 am Probably the biggest factor in cedar longevity is what kind of cedar it is. The known superior cedar for shake roofs is edge grain western red cedar or Alaskan yellow cedar. If they are flat grain or of other cedar types, they will degrade much faster. I work with wood quite often and use a lot of cedar. Although it doesn't rot out like other woods, it will bleach and become brittle as the oil in it dissipates so regular application of oil will most definitely help lengthen its lifetime and preserve the good looks longer. Whether or not it is worth it or will add a significant amount of time depends on the pricing. Assuming a 25 year lifetime, you are essentially depreciating out your roof to the tune of $2200/year. I would get a quote on the actual cost (non-discounted) of treatment over the lifetime of the roof and their estimate of how long it should last with treatment and do the math. Like others mentioned above, especially if the installation was done correctly, frequently walking on cedar shake roofs do a lot of damage. Can they apply the treatment from the ground or bucket lift or do they have to walk on the roof?
One concern is that FAQ linked above by FrugalInvestor states:
and alsoDo not use a topical treatment that: makes outrageous claims (such as a 10 year effectiveness), makes fire-retardant claims, is a sealant, waterproofer or plasticizer, or contains unfortified linseed oil, diesel fuel or crank case oil.
Never seal your cedar roof. Sealing the roof will lock in moisture that would otherwise naturally evaporate during normal weather conditions. Cedar needs to breathe and thus a water repellant type product, rather than a water proofer is the best route to follow.