option 01
option 02
A couple of preliminary thoughts on the structure of the light shells. Option 01 is the most appealing. I like the thickness of the shell in that detail which results in an increase in r-value and extra sound absorbtion through the use of laminated wood decking. I think I may need to add a vented nailing substrate into the system under the rigid insulation. Anyone?
The metal roofing system will utilize z-channel connections and anchors to relieve the stress on the fasteners where the thermal movement of metal has the potential to enlarge fastener penetrations and thus create leaks.
I am somewhat reluctant to paint the interior of the shell wall. I would like to express the natural wood texture as much as possible, but the light paint colors would diffuser the daylight better. The glulam arch ribs with still be stained and finished to accent the natural wood grain. Can a glossy stain provide the same or similar amount of diffused light as a white ceiling or wall? Chris?
6 comments:
Rick,
the thickness of the board should depend on the span between the gluelams: 6" decking spans 15'-20', 1 1/2" up to 5' (see the companion). I would space the gluelams at about 15' apart, 4" wood deck should be enough.
I would add the 2" to insulation, diagonally mounted, mechanically fastened protective board and 30# felt.
You don't need to add an airspace between the decking and the insulation, but I would like to see the vapor barrier below the decking to make sure the dew point doesn't end up within the wood decking.
I think you could achieve your desired look by leaving the vault in natural wood and designing movable wall and ceiling inserts in light colors that don't cover the entire surface- but reveal it behind.
Werner... if I place the vapor barrier under the wood decking it is then exposed to the room side of the structure... this would then require another layer of finish material. I would like to show the underside of the wood decking as finished interior wall surface. In looking through the Kalzip web site, the vapor barrier is placed just under the insulation on top of the decking... although they show metal deck. Is this a problem with wood decking? I understand the concern of with dew point within the decking.
Another potential problem with placing it under the decking would be at the connection of the decking to the arch structure. The vapor barrier would then be "sandwiched" between the structure and deck, which seems a bit odd. Is that a problem?
The spans for the decking will be 18'-0". The arches are located at every two sleeping units, except at the student lounge. Each room is 9'-0" wide. So the 6" decking is the choice.
Anne... I was thinking the other day of looking at that very idea. Maybe even a few that are metallic and more reflective. They will probably be perforated with some acoustic insulation behind them to help with potential acoustic issues of the tunnel like interior and noise from the floor below.
Rick, I love Kalzip...I think its a great product that allows for a co-hesive wall and roof system that is architecturally apealling!! Could work well with your building and could help you address the transition from your more interesting "pike" piece to your lower street level boxes....maybe this system flows from the backside over in one part and down to the areas below...undulating and opening up in various areas dictated by program....
Rick, sorry for the delayed comment, had to run...
The question of dewpoint is really for Chris, but I think the 6" solid wood has sufficient R-value to get the depoint within the deck. I'm not enough an expert on wood to be able to tell you if the wood could take that moisture and work it back out over time, or if we would create a place for rot and mold. You could consider having a series of 2x12 running perp. tothe glulams, strapping parallel and i.e. 3/4" flooring perp the glulams. above the strapping could be a vapor barrier, between the 2x12 ample space for spry-on insulation. a diagonal sheating on the outside would guarantie the curve and be substrate for 30# felt and kalzip.
Werner... revised detail posted. let me know what you think.
Chris... thoughts on NuWool? Have you seen this product. Very impressive product.
Post a Comment