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1 I had repaired enough water damaged sheathing and framing over the years to realize that something was not right. It did not seem to matter what the siding was, any weakness in the systems turned wood to compost. Trade publications in the 1980's verified that I was not the only one with this experience. Building science became a common topic on the job site and details flowed from the field to the drawing board and back about how to deal with it. Flashing theory and practice, new house wraps, new style windows with new style challenges, tight houses, the list goes on: we were trying to keep up with it all. One obvious (at least to us) solution that had to work was to create a space to let water that will get in find it's way out. This was called many different names but rain screen and capillary break both described the theory well enough to this carpenter. Any change to the wall section creates challenges to the interior and exterior finishes. This added wall thickness impacts windows, doors: everything architectural, structural and aesthetic. Making it work takes additional materials and labor. Living in forested countryside, blessed with an abundance of spruce, hemlock and pine we follow the traditional formula using wood siding of all kinds: native, imported, exotic, even nonsustainable but what folks like and are comfortable with. Using rain screen technology we feel confident that the products we install will outlast the carpenters that install them, as they should. We have used ¼ inch lath, ¾ inch furring, Cedar Breather, House slicker and anything that will create an airspace between the sheathing and the siding while allowing the carpenters to install as they normally would; adjusting the siding exposure to align with the window sills, window and door head casing, major trim elements and terminations. Attention to detail coupled with a clear understanding of what the end product must look like delivers a solid, durable product that will still require maintenance of the paint or stain. The advent of cement based siding has forced us to consider some unused tricks in the world of wood siding in New England. It is common modern production practice to run wood siding behind the rake frieze (packed or furred out as needed) as the courses each grow shorter by the slope of the roof. This detail does not trap water as siding cut to butt against a frieze that is nailed to same plane as the siding will. The cement sidewall details also have adopted this technique at the corner boards. The reason for this is the simple fact that cement planks expand and contract more than the walls they are nailed to. Manufacturers of cement siding suggest plenty of caulking and I have seen some poor installations looking even worse after time and water get into those butt joints. Tucking the siding behind the corner boards allows a larger range of motion and more forgiveness. It is not a perfect scenario but is workmanlike and serviceable. Many clients today are attracted to the advertised warranty of cement siding, truly a paint warranty. Followed to the letter there is no certainty that the manufacturer will stand behind it or even be in business, a risk we take with all modern building systems.

2 I am seeing cement siding breaking down in areas where it is too close to grade or if the workmanship slacked even the smallest detail. With a rain screen these errors might never have been a problem or the service cycle might have been longer. Siding Master also sells Furring Master, a good match for cement siding where a rain screen is specified or desired. This brings me to the topic of this conversation. In a recent cluster development, built as long term rentals to local service workers (a common topic in ski and resort communities where housing values and real estate have grown faster than the compensation paid to locals). I was asked to find areas of economy that would allow the homes to be built with state of the art roofing, insulation, and fresh air handling. One place that we could offer some savings over the local preference of painted wood clapboards was vinyl siding. This was not an easy sell to the carpenters on the job but there is plenty of new construction and renovation work that is built locally with vinyl. Economy of product and low maintenance costs finally won out. Since the project would have had a rain screen I was determined to maintain that air space and searched the web for a solution, even if it was wood furring as we have often used. It did not take long to find a better solution in Siding Master. The product is well thought out and manufactured, the price per square is close enough to cedar breather, and working the systems into the trim details and design became the challenge. With four identical houses we thought we had just the right opportunity to perfect our game. To allow color variety and to give the houses some detail we did use some wood trim: Fascia, frieze, band, corners, door trim and bed molding were all wood, painted for the time being the same color as the vinyl. It has been said that assumptions can lead to trouble and in truth they always do. Siding Master requires a particular siding lock profile. The siding we selected from my preferred local vendor (unfortunately only 12' lengths were available) was known to have a nominal thickness and samples seemed to indicate we could proceed without all the parts in hand. The Paradigm vinyl windows, built in Portland, Maine, allow up to a 7/8 siding assembly thickness (Siding Master strip and siding thickness) in a J-channel that in this case was built into an attached vinyl flat casing. Perfect. Any other siding thickness would have required furring out the widows to the plane of the strip.

3 I figured I could do even better with a corner detail furred out only 3/4. Lesson: do not try something new without all the parts needed to verify dimensions. We made it work and I lost some time to the solution. The inflexible modular nature of vinyl siding forced us to select windows and window sizes that fit the module so we could make the siding look like well done wooden siding. To accomplish this the wall was framed and the windows openings set to allow the 4 inch module to rule and it worked. The Siding Master strips were precisely installed around the entire building using a level line snapped on the house wrap at a place the carpenter could see easily and which was set to align with a cutout in the strip. In the gable ends of the buildings we precut all the strips to length and added short offcuts if we needed extra attachment points. The clever starting strip provided by Siding Master is appropriate for renovation work but we needed to modify it for new construction and the particulars of these buildings. We used sections of Cobra-Vent in conjunction with the starter strip to keep critters out of the air space created by the Siding Master strips. This vent is a product we have used for roof venting and rain screen closures already so we had planned on using it anyway. Note the metal flashing we installed behind the corner, similar to J-channel this cleans up the look of the furred out corner. The carpenters quickly learned to use the system and the tools required to bend the fixtures that restrain the siding. Caution is urged as the fixtures (fingers) must be consistently bent and well smoothed or they will telegraph through the siding. Siding master also sells a closure strip that we did not use because of the trim details particular to this project but I believe there is place for them in the market.

4 The system allows the siding to expand and contract. This is critical for a good looking vinyl siding job. I do regret not pushing vendors harder to get longer lengths as the laps in the siding are not perfect. Better than if the siding was installed directly on the wall but not perfect. In closing I am completely satisfied with the product. Siding master is simple to install (but the average experience level of carpenters on this project was 25 plus years) and perfectly provides a rain screen solution that is good for the house, good for the siding and a great product for the housing industry. As rain screen technology becomes mainstream and the expense is proven to be of good value Siding Master will be specified by more builders and architects when vinyl is the siding choice. Solid attention to flashings and penetrations must be a priority in all siding applications, this product is no different.

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