Question: We’re adding a deck and are thinking of either a NanaWall (retractable window wall) or going with more traditional French windows. The basic idea is to integrate the outdoor and indoor spaces. Have you had any experience with such construction and/or any tips on what approach is preferable? The NanaWalls are certainly more money.
Answer: From Alon Toker, president of Mega Builders in Chatsworth:
To fully realize the potential of a NanaWall (or similar) system, the typical door opening(s) should be enlarged. Essentially, the wall will need to be entirely eliminated or else you are basically replacing your sliding/French door(s) with a bi-fold-like system.
The main issue with eliminating the wall would be loss of shear strength, which is the ability of the structure to resist lateral movement, and that is especially critical in earthquake-prone areas.
If you are aiming for an all-glass wall, you should consult with a structural engineer as the city or county will want to review plans and structural calculations before issuing a permit for the work.
To compensate for the loss of shear value, the engineer has several options, some of which might be rather costly such as adding a steel frame across the opening.
To explore your options, you might wish to go to your city’s department of building and safety (or your county’s if you are in an unincorporated area) with a sketch and see what they say. You might also wish to ask an engineer to take a look and offer his/her opinion. This way you would know what you are getting into before you are too far along with your plans.