[Greenbuilding] Glass ceiling

[RT]

On Sun, 18 Nov 2012 09:31:29 -0500, Tim Brown <tim34 at optonline.net> quoted:

> On Nov 17, 2012, at 10:41 PM, John Salmen who wrote:

>> Re-using and re-claiming is also not necessarily a good thing. Do I  
>> want a floor from wood that came from an old factory floor with cells  
>> filled with un-re-claimed heavy metals and toxins?

who quoted gennaro brooks-church who quoted
Clarke O'lSen who wrote:
>>
>>> Something I learned the hard way: if you lap glass panels, water will
>> capilery back into the joint. If you want to make it
>> tight, maybe a bead of clear silicone.
>>> Another hard lesson, the amazing power of that caulk not to let go when
>> you need to take something apart.
>>> Maybe temporary window caulk would be easier to deal with.

Years ago there was a peelable caulking that was intended for interior use  
by folks wanting to seal up their leaky windows for winter and then remove  
that caulking when warmer weather came around so that they could open  
those windows again.

I remember that stuff steenking to low hades, off-gassing some sort of  
petroleum-based solvent.

Aside from the nauseating odour, the "caulk" strategy is a one-off  
proposition. You need to apply new (and steenky) caulk every time you want  
to move from operable to non-operable modes.

A better approach IMO would be to design to allow for the use of  
re-useable gaskets which in the case of this overhead glazing discussion  
would mean the stock neoprene (*not* PVC)  glazing channel that is made  
for use with the single-glazed tempered glass used in patio storm doors.

The inside surface of the channel gets clamped tightly against the surface  
of the glass to create an air-tight/waterproof seal and the outside of the  
channel has a series of small ribs which prevent capillary action from  
occuring between the gasket and the clamping surfaces while at the same  
time providing a protective cushion for the Achilles Heel edge of the  
tempered glass.

I would take issue with BCJohn's argument against using reclaimed wood on  
the basis that *all* of its cells are susceptible to contamination from  
preservative treatments and/or environmental fallout.

I have a hard time believing that any brushed-on or sprayed-on  
preservative treatment penetrating to any significant depth would not be  
removed by the planing process that most users of reclaimed timber would  
undergo for finish work.

The standard for the pressure treating industry for preservative  
penetration was (decades ago when I last looked) something like 3/16" for  
PS-1 grade treated lumber -- the stuff intended for use above grade for  
decks etc ... and 3/8" for PS-1/PWF grade treated lumber  -- the grade  
that must be used for pressure-treated wood foundations.

If you've ever been to a wood pressure-treating facility, you'll have seen  
that achieving 3/8" preservative penetration depth is no easy task. They  
first have to kiln-dry the lumber to render the cells of the lumber  
amenable to accepting the preservative and then they have to poke a bunch  
of slits into the surfaces of the material so that the preservative can  
get in and then they still have to pressure cook it to force the  
preservative into those slits.

I don't think that designing for ease of re-use at the end of the service  
life of a building  is all that difficult. In most cases it simply a  
matter of getting out of the nails and adhesive glop mentality of putting  
things together in bits and pieces and thinking more in terms of "systems"  
... not unlike how commercial buildings are put together.

-- 
=== * ===
Rob Tom					AOD257
Kanata, Ontario, Canada

< A r c h i L o g i c  at  Y a h o o  dot  c a  >
(manually winnow the chaff from my edress if you hit "reply")