Historical Wood Roof Preservation

historical wood roof preservation

The history of wood shingles in the United States dates back to colonial times, and early wood-shingled roofs would often differ from region to region, depending on the types of wood most readily available. In the Northeast, for example, white pine was typically employed. Down south, shingles made of oak and cypress were more common. As the west was settled, redwood and cedar came into use.

From the early days of the roofing, shingle surfaces were coated with oils to protect the wood against rain, sun and the passage of time. By the 18th century, pine pitch coating, linseed oil and brick dust minerals were widely in use. For decorative purposes, shingles were also treated with an assortment of colors, including slate gray and Venetian red. Starting in the 1800s, colors like green also became common on roof shingles. Untreated shingles, by contrast, tend to assume a silvery gray or light brown surface over time, which adds to their raw natural charm.

With the rise of metal roofing on urban architecture during the 19th century, shingles ebbed in popularity. Nonetheless, wood shingles have never truly gone out of style because countless homeowners of each passing generation have continued to favor the quaint appeal that only wood can offer. From the country houses of the Victorian era to the colonial revival in the century that followed, one movement after another has reaffirmed the staying power of wood shingles as a unique, timeless and durable roofing option.

Qualities to Note When Restoring Historic Wood Roofs

Throughout the history of roofing, some of the most distinguished and valued homes have retained their charm and luster by holding true to their original design. As one of the most ageless roofing options, wood shingles are featured on some of the longest standing homes throughout the U.S.

For the sake of historic roof preservation, it's important for replacement shingles to match the originals. To get the right match, the following information needs to be collected:

●      Original wood. A new set of shingles can be cut to replicate an older set on a classic home, but it's hard to achieve the same look and feel without matching the wood type. Therefore, it's best to know which kind of wood was used for the first set of shingles — be it red cedar, cypress or white oak — so that the wood can be matched when you buy replacement wood shingles.

●      Shingle size. The size of each shingle can determine the look and longevity of a given rooftop set. To replicate the look of preexisting shingles, you must take note of the length and width of the shingles, in addition to the thickness.

●      Exposure length. When it comes to the placement of shingles on rooftops, a small portion of each shingle gets covered by the one above it, and the rest is what is exposed to the sun and rain. The length of this exposed portion is important to note before you order wood shingle replacements.

●      Nail pattern. Not all shingles are applied identically from rooftop to rooftop, as some shingle sets are applied with thicker nails than others. The type of nail is also an important factor, since certain types of nails are more likely to offer sufficient fastening strength on select wood types in certain climates.

●      Fabrication method. The look and overall feel of a shingle set is also largely determined by the method used in the fabrication of the wood in question. Were the shingles sawn or split? If the shingles were made by hand, for instance, the overall look will be rougher than if the shingles were made with tools or machines. If roughness was the look of the original shingles, that's the look you want to replicate.

●      Unique features. Surface impressions are crucial to the naked eye, and wood shingles are most often noticed for their distinctive details. Do the shingles have hips or dormers? Valleys or ridges? For obvious reasons, the cut and shape of a given set of shingles must be noted and replicated to get accurate replacements.

●      Decorations. Even though this isn't true for all homes with shingle rooftops, shingles sometimes feature decorative elements. Therefore, you need to make note of any patterns or color-coating that exist on shingles. Alternately, old shingles might be laid out in a unique manner that leaves the nails exposed.

●      Substrate type. The integrity of a shingle set is mostly down to the wood type, design and fabrication method used, but the overall application also depends on the shingle bedrock. As such, an old set of shingles is best replicated when you identify the substrate, be it sheathing or an open lathe.

Any historic wood roof restoration must be done in compliance with local codes, which could dictate the use of fire-inhibiting chemicals. This is generally a good thing. While the chemicals don't impact the appearance of wood, they can often help lengthen the wood shingle roof’s life expectancy.

Important Elements to Retain During the Historic Wood Roof Restoration Process

With some wood shingle roof replacements, it's difficult to make a historically accurate match because information is elusive. Perhaps the house has had more than one roof since it was originally built. Or maybe you don't want the exact same shingle scheme, but do want to retain the classic vibe and the value it carries on the resale market. In either case, the following characteristics should be retained from the original roofing at all cost:

●      Quality. Chances are, the original wood type was chosen for a reason, such as for its texture or strength. Sometimes these choices are merely for aesthetic reasons, but often times a wood will be chosen for its durability within specific environmental conditions. In other words, a suitable wood for southern homes might not be sufficient for homes in regions with harsher winter weather.

●      Dimensions. The size and shape of wood shingles are not merely aesthetic. In many cases, shingle size is selected to fit specific roofing dimensions. Therefore, qualities such as length, width and thickness actually matter when it comes to replacing the shingles on an old home, regardless of whether you wish to replicate the old roofing.

Size & Shape of historical wood roofing

●      Pattern. As with the surface quality and dimension of a shingle set, installation patterns are often chosen for a reason. Based on the slope of the roof, a specific pattern might best facilitate the drying of wood and the drainage of rain. That is why special note should be taken of characteristics such as ridges, hips, valleys and overlaps in the pre-existing roofing pattern.

●      Features. If you're going for an exact replication of the shingle roofing on an old home, decorative features such as color or unique nail patterns should be duplicated to the letter. Even if you don't love the style, the unique roofing features of an old house can contribute substantially to its resale value. This is something to especially keep in mind if you plan to sell the home at some point in the future.

Areas Where New Shingle Roofing Materials Can Differ

While it's necessary to match certain aspects of old shingle roofing as closely as possible, other areas do allow for more leeway. The characteristics that can differ between old and replacement roof shingles include the following:

●      Wood species. Some old homes with wood shingles were built long before the availability of stronger, more durable options. As such, if you wish to take liberties with your new roofing selection, consider a different wood type if the wood currently in place could indeed be of a higher quality.

●      Fabrication. If you'd prefer sawn wood shingles over hand cut, or vice versa, go with your preference, especially if there's no noticeable difference to the naked eye.

●      Flashing. If your house was built before the advent of modern flashing, it could be wise to have this added to the roof during the process of shingle replacement. As long as the flashing is sensitively applied, it should greatly enhance the quality of the new roof.

●      Sleepers. When you consider that newer and newly renovated homes have more difficulty ventilating naturally, you might consider sleepers for the roof. If the interior attic has been re-walled and insulated, the addition of sleepers could make it easier for the roof as a whole to breathe. This, in turn, could help prevent moisture buildup in the shingle wood.

●      Nailing. If a different method of nailing would make things more secure for the new shingles, go with that method, especially if it makes no difference to the visual pattern.

Preserving Your New Wood Shingle Roof

When it comes to wood shingles, successful preservation of a new or historic wood roof is best achieved with proper care and prevention of harmful buildups on the rooftop. The longevity of shingles can largely be determined by factors like exposure, maintenance and various attributes of the wood itself, as well as the following:

●      Thinness. The thinner the set of shingles, the less strength they will have to withstand the elements and remain in single pieces as year-by-year impacts pile on. Therefore, thin shingles should be inspected twice annually for signs of wear or damage.

●      Durability. Some types of wood are more durable than others. Shingles made of cedar wood are among the strongest options on the market, and they are most likely to last the full life expectancy of a given set of wood roof shingles.

●      Exposure. The impacts of wet winters and hot summers can take their toll on a set of shingles. Rain water, for example, can wear away at shingle wood, especially if the draining fails and water accumulates along the roof edges. Ultraviolet rays can also compromise the integrity of shingle wood.

Successful wood roof preservation

●      Slope. The steepness of a roof can greatly affect the lifespan of wooden shingles. If the slope is sharp, rain is likelier to slide right off the roof and out through the drains. Likewise, sharp slopes limit the amount of direct contact a roof has with the sun.

●      Moss. The growth of moss or the formation of lichens can slowly eat away at wood roof shingles. Moss forms from a combination of airborne spores and moving water. Wherever moss forms, such as on wood, it's an indicator that something is wrong with the underlying surface.

●      Ventilation. Wood roofs need sufficient ventilation to dry after each downpour. Before the 20th century, this was relatively easy, because homes in those days weren't equipped with ventilation inhibitors such as insulation. If an older home has undergone interior renovation work, the wood shingles might be left with a reduced capacity for ventilation.

●      Overhang. Encroaching branches can be the biggest enemies of rooftops. An adjacent tree, for example, could get struck by lightning and send a heavy branch crashing down on the shingles. Even if the overhanging branch remains intact, the falling of leaves and pinecones onto a rooftop is not healthy for shingles.

●      Pollution. Elements in the environment can slowly eat away at wood roof shingles. Pollutants from nearby factories, for instance, can send airborne toxins to the exteriors of houses in any given area. As these particulates settle into the wood, shingles can lose their compositional integrity.

●      Maintenance. In many cases, the aforementioned problems can be stopped before they spread with regular rooftop maintenance. If a roof is checked once or twice per year — preferably before each summer and winter — issues such as poor drainage, moss growth and debris pileup can be halted before they spiral out of hand and lead to costly issues.

●      Installation. Sometimes, the worst problem with a set of shingles is the way they were installed. If a prior installation was handled by unskilled roofers, all the maintenance, drainage and overhang prevention will do little to stop the early demise of unfortunately laid shingles.

As one of the most reliable yet element-sensitive of historic roofing materials, wooden shingles should be replaced every 30 to 60 years, depending on the type of wood used. However, shingles comprised of heartwood straight grain can sometimes last twice as long.

Replace wooden shingles every 30-60 years

 

Get New Wood Shingles or Shakes From Custom Shingles

Wood shingles are widely loved for their timeless appeal, but what are wood shingles without the unique designs that make them the most flexible of roofing options? At Custom Shingles, we create shingles to match virtually any design concept imaginable. Homes of all ages with wood shingles and siding can be revitalized with any given number of styles on offer, from Thai to Tudor and from Seawave to Storybook.

If you're after a bold and striking design for the roof of your home, consider one of the pointed options such as sawtooth, chisel or diamond shingles. If a rounded look is more befitting to your tastes, consider octagonal or fishscale shingles.

With over 40 years of extensive experience with restoration projects, we can help you find the roof of your dreams. If you're grappling with the wood shake roof vs. shingles dilemma, we have an array of both hand-cut and machine-cut styles that are sure to bring you to a confident decision. To learn more about the range of roofing options we offer at Custom Shingles or to get a quote for your roofing project, contact us today.

Custom Shingles to Match Historical Wood Roofs