Finding The Right Substrate On The New England Coast

The stormy, wet weather on the New England coast makes for a harsh environment for exterior building materials. When east-coast firm TMS Architects contacted custom millworkers King & Company to build exterior architectural elements for a home in a coastal community, finding a substrate that could withstand the weather was a chief concern.

Of course, many materials available stand up extremely well in harsh environments, but that wasn’t the only variable. According to King & Company owner Bob King, “Tim at TMS contacted us to build some exterior architectural keystones for a house, and he was concerned about the house’s proximity to the sea and potential damage over time if we were to use something like wood.

Although I’ve used Azek in the past for similar projects, I found out about HDU through a friend of mine who is a sign maker and so I started using that a few years ago as a replacement. What really sealed the deal for this project was after I tested a sample of Coastal’s PBLT-20 HDU and saw how much finishing time it would save me. On top of that, Azek is only 1.25″ max. thickness – which meant a lot more labor for us to laminate it to the necessary thickness, whereas I could order the Precision Board 3.25″ thick no problem,” says Bob.

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After the keystones were CNC routed by King & Company, they were sent to master home builders DePiero Properties in Newburyport, MA, who primed and installed them at the custom home they are building in Newbury, MA. The keystones match perfectly with the historic ambience of Newbury, which is one of the oldest cities in the USA, and was actually settled in 1635 by about 100 pioneers from Wiltshire, England!


As you can see, the house is not completely finished yet, but we decided to share this story early as it is such an innovative application. A follow-up article with completed pictures will be published in winter of this year.

King & Company has been in business since 1986 and specializes in high-quality, custom staircases and millwork in the New England area and worldwide. Additional information about the hand-crafted masterpieces made by King & Company can be seen at:


TMS Architects have been designing high-end commercial and residential buildings throughout New England since 1984. Please visit their website for additional examples of their design skills:


DePiero Properties build custom luxury homes in Greater Boston, southern Maine and southern New Hampshire. Having completed over 200 homes throughout the course of their existence, DePiero are experts of the trade. Additional information can be seen at:

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