Here on our website, we have lots of different content where you can learn about the historic building construction anatomy, design, architecture and structural preservation needed to maintain and preserve these historic buildings here in Washington DC. We specialize in historic restoration and repointing and as an adjacent topic, we have looked at facade terminations a few times over the past few years we’ve written about different details related to rakeboards, and the transition between the historic masonry facades of buildings and the adjacent systems of the building such as the rooftop and cornices and exterior crowns. Today, we are looking at a particular example of a rake board along the side of the building. This particular side facade of the building is exposed along its length directly on the street.
The picture below shows the rake board along the top of this facade wall where we exam the condition of the rakeboard next to your carpentry this past week. The roof above the exterior facade terminates at the parapet in an applied or overlaid coping that spans the width of the parapet and essentially covers the parapet from the exterior Elements which would set on top of the horizontal areas of the brick wall. Without a stable and impermeable metal barrier covering this parapet, over time, since this area of the wall is a horizontal surface, water would sit, accumulate, and eventually deteriorate The Masonry and work its way deeper into the masonry wall assembly if it wasn’t covered with an aluminum coping, in this example.
It’s good practice, not just to cover the top of the parapet wall with a coping metal, but it’s also better practice to build a architectural detail that serves a functional purpose to extend the termination or drip edge, in this case, farther away from the edge of the masonry vertical facade. That extension or projection away from the front facade allows most typical precipitation events to have water directed a little bit away from the facade which allows non-wind-driven rain to drip without saturating the wall, in many cases.
In this particular case though there’s a problem. The crown or cornice used at the rake area of the wall, as part of this rakeboard assembly, is a wood that is not historic and is more susceptible to water damage. This is a historic building but this is not this particular element is not historic because it was changed and more recent years when the most recent roof was installed originally about 20 years ago. If you look closely in the photo below you can see the rotted wood at the surface of the rake board.
The next photo below shows even closer view of the same area of rot and deterioration in the wood trim. Right in about the center area of the rot there is a zigzag seam that runs through the wood at the rake board. This seam is part of the factory or mill manufacturing of the wood. This isn’t natural and it’s also not entirely common. Natural wood doesn’t have seams like this in the linear run of a board. This is called finger joint wood. It’s kind of in an in-between area because it’s not actually completely fake but it’s also not completely real either. The wood pieces are small chunks that are cut at their ends in this zig-zagging kind of pattern to allow for more surface area in contact with the adjacent piece when they’re joined together. Then after the zigzag type cutouts are fitted together between one board and the next and a butt joint type of configuration, they are then glued pretty relatively tight or well connected bond.
The biggest problem with this type of wood, when used and installed in an exterior type configuration, is that it’s generally not intended to be installed in the exterior building. Fingerjoint wood is generally made from fast growth coniferous trees. This type of wood, is particularly susceptible to exposure of moisture. For this reason it’s better to not install this type of wood trim outdoors. Even in a case like this where it’s partially covered, it’s still going to get wet with directional or wind driven rain, and it will deteriorate on an accelerated schedule.
We can Help
Our company focuses on historic restoration more than modern building upkeep, maintenance, and construction, but our company understands both types of construction very well and a full picture well-rounded approach is needed in any niche in the construction industry. Although we focus on historic restoration, repointing, tuckpointing and historic brick repair, our company also has technical knowledge and competencies in the areas of modern and contemporary construction as well as we become one of the leaders in that area of the market today. Understanding both historic and modern or contemporary construction is useful because both aspects help understand the challenges and potential solutions for challenges in building science and construction.
We can help with a variety of historic masonry restoration needs and upkeep, from modest tuckpointing and or repointing to complicated and extensive historic masonry restoration. Infinity Design Solutions is a historic restoration specialist contractor specializing in both historic masonry restoration such as tuckpointing our repointing, and brick repair. If you have questions about the architectural details or facade of your historic building in Washington DC, reach out and say hello and if we can help we’ll be glad to assist you. You can email us or call us on the telephone at the following link: contact us here.
