Monday, June 22, 2015

Timeline - Design Evolution - Wall Cladding

Past Three Years


Preconceived Ideas
Dorothy and I are not fond of vinyl siding.  It is unappealing because it is ubiquitous, looks cheap, is petroleum-based, has a lot of embodied energy, is subject to wind and hail damage, has a short life span and mostly ends up in land-fills. The commonplace 4 x 8 sheets of cedar-veneered plywood would not be a bad choice except for requiring perpetual maintenance.  Real cedar clapboards are beautiful but have the disadvantages of requiring ongoing care, coming from old growth trees and being expensive.  Our search for alternative cladding that was inexpensive, low-maintenance and green took some unexpected turns.

Fibercement -- the New Green
My green building research kept pointing me towards fibercement siding as the greenest
Fibercement lap siding
choice for cladding.  I even went so far as to buy a used electric nibbler to use for cutting it someday.  It is made from cement and renewable FSC-certified (Forest Stewardship Council) wood, holds paint two or three times longer than wood, is virtually wind and hail proof, has a long lifespan and comes with a reasonably low level of embodied energy.


SmartSide
At one point, a building supply salesperson tried to sway me away from fibercement with a product called SmartSide that appears to be an OSB-like board that can stand the weather. He gave me a sample and told me to take it home and soak it in water for a while to demonstrate its durability. I did and it swelled.  I emailed the company and was told that it was not designed for underwater, just wetting as would be expected with any cladding.  Fair enough.  It is indeed a green product since it comes from renewable wood chips from plantation trees and the finish comes with a long-term warranty.  For green-ness, its other attributes pretty much match those of fibercement.

Metal Siding?
Until two years ago, metal siding had not entered my mind. When my stepson , Keith, said that he was going to use it on their energy efficient house, my first reaction was, "Are you kidding?"  Bu
Siding underway for Dawn and Keith's house;
 note that, for energy conservation, the amount
 of glazing on north and west sides is minimal

t after I helped install it, I came to realize that he had made a wise choice -- it's definitely an unique finish for homes, it's 
DIY-friendly, it's virtually maintenance-free, it lasts for at least half of a century and it has a recyclable end-life. If there is a knock against metal siding, it is that it has fairly high embodied energy which, to some degree, is off-set by its recycled content.

Comparative Pricing
When the various options for cladding were compared, the SmartSide was the most expensive, the steel siding was the least expensive and fibercement was intermediate. After being so impressed with the steel siding that we installed on Keith and Dawn's house, the price sealed the deal for steel.

Installation
The panels that we installed on Keith's two-and-a-half story house were long -- some were over twenty feet -- which were a struggle using ladders instead of scaffolding. All of our walls are single story height which will make installation easier. The color we have in mind is white because of its timeliness and its high reflectance against solar gain in summer.

Well glazed southern exposure
The one thing that I would change from the typical installation is the trim at the corners and around the openings.  If the appearance of the metal trim sold with the panels could be modified to look more like the trim used with old-fashioned clapboard or fibercement siding, the house would for us appear more "residential" and less "commercial". Accordingly, I plan to rabbet well-dried pressure treated 2x's to receive and conceal the edges of the metal panels just like the metal trim does. Then, in order to minimize maintenance, I will paint the wood on all four sides with the best paint I can find and hide the metal J-mold (that would ordinarily be exposed around the openings in typical installations) under the rabbets.

Diagonal Panels?
At the time of this writing, Dorothy and I are toying with the idea of installing some panels on the front of the house on the diagonal to create interest and originality. Doing so will shunt runoff towards the window frames instead of directly downward. Therefore, the rabbeted window frames and underlying J-trim will have to be detailed precisely so that the runoff doesn't linger and challenge the efficacy of the flashing around the openings and the moisture barrier under the metal.