To Clarify:
IMHO: I have concerns regarding the concept of "building-out" additional soft "sub-layers" of materials on a home's exterior. (Rigid Foam board installation under vinyl siding is one thing -Vinyl is never fastened tightly - because this allows it to expand and contract)
Attaching strapping
over permeable foam board, and then attaching your solid material siding onto that strapping, creates a layer of non rigid material between your hard material surface and your home's exterior sheathing. This can cause alot of "irregularities" between the surfaces, since the foam is so pliable and strapping is so prone to warpage, bowing & twisting when not attached solidly.
Here is information from the James Hardie site:
"Hardiplank lap siding is installed over braced wood
or steel framing spaced a maximum of 610 mm o.c.
or to minimum 11.1 mm OSB sheathing or an
equivalent thickness of plywood sheathing (Figure 1).
Hardiplank lap siding can also be installed over foam
insulation up to 25 mm thick. Irregularities in framing,
sheathing, and/or foam insulation can mirror through the finished application..."
(from):
http://www.jameshardie.com/pdf/install/install_plank-canada.pdf
To me: Adding strapping into the equation (on top of the foam) would compound the possibility of loose attachment points and irregularities - for the trim boards, as well as the siding itself. There is also the issue about roof line drainage and door/window surface-thickenss drainage that can happen when adding that kind of sub-layer thickness onto an exterior surface (foam board with strapping over it).
I am not stating this as rule, but as something that has the high probability to create problems. Even if some architects think it's a good idea, does not mean that it is. We have fixed many, many exterior and interior "architect ideas" that didn't end up working the the way they thought it would, or the way something was designed or listed on their plan details.
Linear Mode
