Tag Archives: oiling cedar

Cedar Roof General Maintenance




cedar roofs are unique


There are important factors to consider when planning on doing maintenance for a cedar roof. Cedar roofing requires very particular methods on upkeep that you wouldn’t need to consider on asphalt, tile and other roofing types.

When making decisions on the right service plan, it is crucial to understand how cedar roofs age, how they weather and why shingles buckle,crack and cup. Questions to ask yourself during the deciding phase of the right plan for your cedar roof are:

What is General / Preventative Maintenance ?

If your roof is still in good shape general / preventative maintenance can keep it in that condition. Preventative maintenance at PW&G consists of:

  • An inspection that covers all areas of the roof. Specifically areas where water intrusion is common.[1]
  • A blow off of debris. It is important to keep cedar roofing free from pine needles and leaves as these can seriously damage roofing.
  • Spraying an organic chemical compound to kill any moss and its root system.[2]
  • A check of the gutter system along the roofline and a thorough cleaning when necessary. 

These services can prevent many of the issues that cause cedar roofing to fail. Cracked, cupped and warped boards all start with excess moisture, preventing cedar from breathing. From its installation method and throughout its life cycle cedar must be able to dry off and release excess moisture.

Anything that prevents cedar from breathing is the primary culprit in the majority of all cedar roof failures. In our opinion culprit number 2 would be the excess stress cedar must go through to release that excess moisture and it’s why we are firm proponents of oiling cedar roofs to prolong their lives. 

In summary we have created this short post to help you in making an informed decision about the correct maintenance program for your cedar roof. We hope you have many years of life left in your cedar roofing, as many of these types of roofs are beginning to disappear as a roofing option all throughout Western Washington and the nation. We believe the maintenance required to keep a cedar roof in top shape is a fair exchange for the insulation benefits, the beauty and the appeal cedar roofs give a home.

Reference and Informational Material


[1] System components checked during an inspection are: The ridge caps, the field or body of the roof , connections to vent pipes and vent hoods , skylights and areas around chimneys.

[2] Our Preferred Chemical Application for Moss Control 

[3] A really great video by the guys at roof to deck on the care and appeal of cedar roofing. 

[4] The Cedar Bureaus Maintenance Program Manual 

[5] Why Wood Roofs Weather 

[6] How Cedar Roofs are Installed Diagram 

[7] Our Take on Why Cedar Needs Oiling

[8] In All Fairness. Why Cedar Roofs Don’t Need Oiling PDF . You Decide

[9] After the Quest. Decisions on Wood Appearance



Restoration of Old Wood | Making the Right Decision on Appearance


Example Photo Used for Descriptive Purposes Only

The 100 Year old Trellis

100 Year old Trellis Seattle
The following question was recently asked by a potential client on restoring a 100 plus year old cedar trellis and it made me think of  the best way to answer him. In this post I will be discussing some problems and issues you might face in deciding whether to restore your wood project.

I have included the actual E-mail with some edits to make it easier to understand as well as some photos for clarification and a wee bit of redesign on the layout…. for appearances’ sake ! Hopefully this exchange helps you in deciding what the result of a restoration would look like and what the challenges are in achieving a client’s desired look as well as limitations on just what a restoration can do. 

In your opinion, would the end result of your restoration produce a renewed natural look to the cedar?


We could get the trellis to look like it was installed yesterday. We could also make it look completely natural. Unfortunately the problem with that process is as follows:

Cedar is a porous semi moderate softwood. It can not be sealed. It depends on the pores it possesses naturally to soak in and let out moisture. I mention this because the longest lasting option in making wood look natural are all polyurethane based clear coats that seal the wood.


Softwoods and Hardwoods and Why it Matters 

wood pore differences hardwood v softwood

Click to Enlarge

Cedar pores are larger,spread out farther and dispersed to keep and release moisture. Hardwood pores are tighter, closer and more numerous. Cedar must breathe and have the ability to release moisture because its pore system is much larger and spread out then the hardwood .

The best application for cedar is an oil based semi-transparent stain. The best option in choosing a color would be to go as rich and unnatural as possible with the understanding that the color will fade out, as all do. By going darker you are prolonging the maintenance schedule.

It is also easier to keep up a darker color, because maintenance would consist of lightly reapplying as opposed to doing a whole restoration from start to finish to keep the cedar in top shape, appearance wise. For examples sake, this quote from the Cedar bureau, discusses a deck, but the type of lumber is the same and the process is the same: 

 From the Cedar Bureau:

Decks should never be allowed to weather before finishing.The simplest, but most labor-intensive, finish to keep up on a cedar deck is a water-repellent preservative, which may have to be applied annually. The next easiest is a semi-transparent oil-based stain. Both types of finishes are extremely effective in stopping the absorption of water and are recommended


Decisions on Appearance and Why we Don’t Get Involved 


Click for the Video

A water repellant preservative is essentially a clear coat that reflects water with no pigment in it. A semi-transparent oil based stain is an oil with pigment added to it. The differences in maintenance and longevity between an oil and a water repellant preservative are striking. I’ve attached a handy video to help explain it better. 

As a professional my job is to recommend the best option based on experience and to preserve and protect your project, while providing the most cost-effective option  . The final decision on appearance, however, is the clients.

I may like a purple deck with green stripes, you may think me a circus clown. I leave the decision on color to the client for that reason.

What I can do is pick up to ( 3 ) samples to show you what you might get after the restoration is done. To further your understanding of what the trellis might look like after a restoration with a semi transparent stain I have attached a visual aide :


Adding a pigment to oil



Cedar_Roof_West_Seattle_ Before and AfterWe recently completed a cedar roof restoration in Shoreline, WA. The use of 2 different pigments gave the roof a natural wood look. One of the things I never liked about adding stains to wood is how unnatural the even color looks on a roof. We kept the oil that we always recommend but added just a little bit of tint . The overall appearance was night and day as can be seen from the photos below.


ChevronThe use of a pigment when oiling a cedar roof goes along way in both protecting the roof and making the appearance uniform. When cleaning sometimes up to 3000 square feet of roofing , you will definitely miss small spots or have off coloring due to either patches in the wood or just the color differences some pieces of shake have when you’re done cleaning. The pigment helps blend in any darker spots and when mixed with our preferred brand of shake oil , gives the roof a look I have never seen before on any stained cedar roof before.

One of my favorite things to see is the look on the customers face when we are done oiling and adding pigment. Most of the time its pure shock that we could get the roof looking this way again.I am always surprised myself in the big differences either a little less oil, or pigment can have on a roof.

There are many stains who try giving this appearance to a roof but they fall short in their levels of protection , like a cedar oil does. We discussed the benefits of oiling a cedar roof in this post.


Cedar_Roof_Seattle_Experience plays a key role in darkening and lightening certain areas of the roof when you are staining it. There are times Ill slightly mix up the ratio of oil-lacquer thinner and pigment to give the roof an off color. Other times depending on the coloring of the siding, Ill add a natural cedar and also a smaller amount of blonde stain to the mix to really mix it up. What’s left is a finished product like the one above , where 2 different colors created a unique and natural wood look.

Cedar Roof Oiling is it Necessary?


pdf-flatThere is a big debate on the benefits of oiling a cedar roof. A comprehensive and great research paper was written by OSU students, referenced in EC1271, September 1988. Their exhaustive research neither discounted nor encouraged oiling of cedar roofs. As stated in EC1271, originally Cedars mass only contained 3% of its weight in oil. With such a small percentage of its weight to begin with being oil, the debate on replenishing is faulty.

We are not stating that the oils should be replenished. We are advocating oiling a roof in Seattle to prevent rapid expansion and contraction caused by UV rays and rainwater. The stress of shrinking and enlarging cause wood to crack, it is our belief, that oiling a roof stops the expansion and contraction from causing damage to the shingle. The oil allows natural contraction to happen without stressing the wood it is applied to. You can visit the following if you are looking for Reliable Roofing for Stoughton roof installation.


chevronChevron shingle oil is a superior product for oiling cedar roofs it is of low velocity and transparent. The application doesn’t change the appearance of wood; instead it gives the wood a wet look.

Although higher in price than other cedar oils, the history and its long-established reputation among wood restoration experts make it possibly, the best choice for oiling a cedar roof or fence. 

There are many benefits of Chevron Shingle Oil such as:

  •  Its established reputation.
  •  Its ability to mix well with solvents.
  •  Its lasts when applied: many homeowners have said their oil treatment lasts 5 years or longer.
  • It’s easy to apply. A backpack sprayer with a round tip or flat-headed tip work great. There is no need for paint sprayers.
  •  Its ability to be mixed with stain.

When deciding to oil your roof, it should be done from the day it was installed. The ability to repair a cedar roof once the damage has been done is nonexistent. Maintenance is major issue for wood roofs. There are ways to treat cedar for moss that differ greatly from the way we would treat a composition roof. On average a 1200 square foot roof area costs from $16,000-25,000 dollars, according to homewyse. Yearly maintenance can run you about $400. When deciding to buy a home with a cedar roof or having it installed, budgeting for maintenance should be the first thing you do. The unexpected result of not maintaining your roof, can seriously hinder your economic circumstances.