When I last reported on exterior materials, some 5 months ago, we were looking at the products Cembonit, Trespa and Paperstone. Today, we’ve narrowed down our needs, but still haven’t narrowed down the product selection.
Per the design drawings you can see that we’ll be using planks on one side and panels on another. The planks will be installed in a rain-screen application, while the panels are applied directed to the substrate (due to firewall requirements from the city of st louis).
We’d also be needing certain sizes, a smooth finish, a manufacturer who supports a rain-screen application and someone who can pre-paint all the materials so that we don’t have to paint on-site.
The latest list of products is:
1. James Hardie – most mainstream cement board available, also known and hardi-plank. You can find this at your local Home Depot in some styles. Presumably the least expensive, if its at the HD. This manufacturer does not recommend or warranty against a rain-screen application. Hardie has a section on why they are green and sustainable.
2. Certainteed – another large materials conglomerate. Limited color offerings and unclear whether they warranty against a rain-screen application.
3. Nichiha – Japanese manufacturer who sells out of Georgia. Product can be pre-painted in any color. Product is supposedly autoclaved, meaning that it can withstand much more wear than any non-autoclaved product because of the intense pressure and temperature which it was manufactured at.
4. Cemplank – an smaller supplier who my architect thinks has been purchased by James Hardie. This company produces a smooth plank in the right size which can also be painted any color.
In terms of sustainability, it’s so difficult to tell anymore since every manufacturer claims to be sustainable. Cement board is definitely a product which is difficult to distinguish the green washing vs. the true green advocates.
Stay tuned to see how this difficult decision plays out.