We’re currently bouncing back and forth between a subcontractor’s incomplete fire protection and a hardass building inspector (the kind you really want, actually). I picked up the incomplete work this weekend and we’ll see if we pass the re-re-inspection this afternoon. In the mean time, I wanted to dish details on siding. When I find time I’ll add pretty pictures.
TL;DR – Given our options and budget, we’re using painted Hardie siding, furred/spaced off of the sheathing and vented at the top and bottom… in most places.
Siding material determines the look of a building just as much as the shape. “Sustainable” guidelines urge materials that require less energy to produce, to maintain, and are lasting. While we LOVE the warmth and texture of cedar siding, it requires fairly regular maintenance. While vinyl is durable, it looks unnatural and has a high environmental impact (see blue vinyl). One industry answer to meet demands is a fiber-cement composite, (some makers use recycled fibers), and comes in both panels and shingles.
We wanted integrally colored fiber cement; it requires no finish, or refinishing if scratched or gouged. Zero maintenance. There are few manufacturers. We found two serving our area – SwissPearl, and Silbonit. The first is over 6x the cost of regular fiber cement, and the second, over 2x. Too much for our budget. (Admittedly, we were never provided the breakout cost for exterior paint for a real comparison).
Another option is a recycled paper product from Richlite. Again, over 2x the cost. There are also laminated composite panels like Parklex, EcoClad, Trespa, which can come with wood grain finishes, but are again about 6-7 x the cost of regular fiber cement.
Our original design included aluminum “reveal” joints (seams) between panels. These provide a slick modern look. Fry Reglet, EasyTrim, and Tamlyn are some makers. Through a change order, we “value engineered” these out of the project, opted for wood trim “battens” to cover the panel seams, and saved $2600. We lost a really slick detail, but the trade-off adds up quickly.
In the days of cheap labor lap siding would be mitered at corners. It’s typical now to use a vertical piece of trim instead to simply cover the corner. We, however, used a pre-formed metal product to mimic the mitered look, providing an uninterrupted horizontal line. Our builder, his supplier, and installer was unfamiliar. On the very first corner installed, the sub contractor used a vertical trim piece because the metal corners weren’t delivered. Melissa commented that this is like a kid saying “I didn’t see a meal on the table, so I ate candy for dinner.” The trim was taken down and the corners were installed as designed.
An age old method, forgotten but seeing a recent resurgence, is use of a “rainscreen.” This is where the siding material stands out from the surface of the exterior plywood on strips of material 3/8″ thick or more (furring). This provides a secondary drainage plane and airspace for vapor to dissipate. We’re learning that this increases the performance and life of the wall assembly and the siding material itself.
There are two versions. One has open joints or gaps around each siding piece. It’s dead sexy because of the contrast between pieces and the stark punctuation of deep shadow lines. However, it requires a more expensive (UV resistant) house wrap on the plywood surface underneath, and seems to me like an invitation to nesting insects like the mud-dauber wasps. We opted for the other version where the only venting gaps are at the top and bottom of the wall (and openings) and is protected against insects with a mesh.
Furring is/are strips of material between the substrate and finish. I called for 1/2″ treated wood in the drawings, following any requirements of the siding manufacturer for warranty (some recommend a rubber strip between the siding and furring). The good guys at BUILD LLC have success ripping down composite decking for this. And a good friend pointed me to Cor-A-Vent, a hollow plastic furring with a proprietary insect mesh vent/drain for the top and bottom. The sub had figured in 7/16 plywood for furring. We sourced Cobra Vent and ripped it to 3″ wide sections for the insect mesh.
It eventually became apparent that the builder and his sub were not familiar with a rainscreen application. What’s worse than your builder/sub not understanding something specified (like a rainscreen): NOT ASKING QUESTIONS. The work was half way done before I showed up and pointed out that there were no vents above or below windows and doors. The argument: “but then you’d have a gap, and that would look weird!” I overestimated their comprehension and failed an opportunity to bring them up to speed. Who looks at the drawings anyway?
We’ve learned time and again that the sub contractors should ask more questions and make fewer assumptions, especially when the drawings show something atypical. (The electrician has been exceptional, asking questions at every step!) The thing is, everyone (including you and me) wants to perform their job as efficiently (easily) as possible, which tends to overlook the big picture/end result. That’s why general contractor selection is critical, because coordination is their job. An excellent GC will coordinate work before it starts. A good one will make sure it gets done right, even if it has to be redone. And a bad one will do it their way and convince you to leave it.