[Greenbuilding] R20 window insulation?

Fri Jan 7 11:21:40 CST 2011

Unless you get an industrial adhesive, the adhesive backed Velcro will pull off whatever surface it is stuck to in a few months of use.  Velcro pulls a lot harder than magnets, and the magnet adhesives fail pretty fast from the pull-off force.  Whenever you take down the shutter, you pull pretty hard on the Velcro.    Any fastener you use should have a lot of pull-out strength.  Staples will be gone pretty fast.  I can't think of a fastener that would hold Velcro onto foam, unless it was some kind of rivet with a big ugly washer on the backside.  There will be a fish-mouth gap between every fastener as the Velcro stretches over time, frustrating your attempts to make a seal.  Yeah, I've tried this before and gave up on it.  YMMV. 

If you are meaning that you only use one side of the Velcro, kind of as a gasket, and not using the Velcro hooks, then the sealing ability will depend on how flat you can keep your Rmax.  As it tends to warp, any gasket-like material will become ineffective.  Gaskets on the edge of the Rmax tend to get wiped off as they are inserted.   That's why I started to go with force-fit shutters, that just slide into the window sill.  Some times I glue a little block of Rmax on the back for a handle.  Painted, it doesn't look too bad.  

Since Rmax warps, and the shutters take a beating from daily up-and-down, there are a lot of ways to install them that won't stand the test of time.  

--Lawrence Lile, PE, LEED AP, CEM

> -----Original Message-----
> From: greenbuilding-bounces at lists.bioenergylists.org [mailto:greenbuilding-
> bounces at lists.bioenergylists.org] On Behalf Of Lynelle Hamilton
> Sent: Friday, January 07, 2011 9:05 AM
> To: Environmentally-preferable design, construction, building elements
> Subject: Re: [Greenbuilding] R20 window insulation?
> 
> What about using the loop (soft) portion of Velcro on the edges?  It
> would let some air through, to be certain, but may give a snug fit.
> There is adhesive back (don't know about its durability) or you could
> glue or staple, As there's no vertical tension on it, stapling may work OK.
> 
> Lynelle Hamilton
> 
> On 07/01/2011 09:58, Lawrence Lile wrote:
> > I've been using Rmax interior insulating shutters for quite a while.  Mine are pretty
> simple - some of them just force fit into the window frame, I paint the inside (gotta
> prime them first - or the Rmax logo shines through) and paint the edges after duct
> taping them with white duct tape.  Some of them have magnetic seals, some not.
> About as red-neck hillbilly a solution as you can come up with.
> >
> > Have a lot of trouble with magnetic strip seals.  They can pull off of the Rmax.
> They don't adhere to a painted wall worth a darn, and I end up nailing them on
> every 8".  Strip Magnets are also ugly. I probably won't use them again if I build
> another shutter.  I took some of them off and converted those shutters to force-fit.
> >
> > The slickest insulating shutters I have use button magnets.  I carefully core out a
> hole in the back of the shutter, and set a powerful button magnet just below the
> surface of the foil.  Then I stick it onto some metal to hold it, and squirt some
> caulk behind it to hold it in place, patching the hole finally with some wallboard
> paste.  Paint the back the same color as the wall.  Magnets are invisible. These
> stick to the wall because there is a metal bead in the sheetrock return around my
> windows.  Won't work with wooden trim or plastic sheetrock edges.  But they stay
> up by themselves invisibly and don't warp as bad as some of the other methods.
> You could also make these by drilling a hole all the way through and sticking duct
> tape on the window side, with a magnet inside the foam against the tape.
> >
> > Some of them have two layers of Rmax, one that fits outside the window frame,
> and one that force fits inside the window frame.  These warp less than a single
> sheet, and seal up better.  They are bulkier and a little heavy on a large window.
> >
> > None of these seal very well on the edges.  The force fit and two-layer ones have
> the best seal.  I know that insulating shutters are less effective if they don't seal on
> the edges.  I do get quite a bit of condensation, even window frost, on the worst-
> fitting ones.  The condensation isn't good for the wood on my windows. Oh well. I
> have never found a good edge sealing material that holds up.  Duct tape, folded
> into a flap, actually works pretty well with a tight-fitting foam insert.
> >
> > All of my shutters are either 3/4" or 1.5" thick, making them about R4 to R8.
> There are diminishing returns for every extra layer of insulation you add, and I
> figure this is a helluva lot better than R2 windows.  Fixing the leaks around the
> edges would do much more good than adding more layers. Thicker ones are bulky
> and awkward if the windows are large. Assembly with a 6" air gap (R2.7?) is
> probably R12.
> >
> > Some of them have a little plastic window, made of that shrink-to-fit plastic and
> double sided tape.  I have one window that the cat looks through when he wants in
> the sliding glass door, I have another one that I can watch the back yard bird
> feeder through.  I highly recommend using some little windows, so you can see
> who is knocking on the door or watch the bird feeder.  I leave all these shutters up
> on cloudy days, and little windows make the place less cave-like.
> >
> > It takes 30 seconds to take down all the shutters in the living room.  All the
> shutters on the North and West walls stay up all winter. Every time I get grumpy
> about the chore of taking them down I think "Just thirty seconds".
> >
> >
> > --Lawrence Lile, PE, LEED AP, CEM
> >
> >
> >> -----Original Message-----
> >> From: greenbuilding-bounces at lists.bioenergylists.org [mailto:greenbuilding-
> >> bounces at lists.bioenergylists.org] On Behalf Of Bob Waldrop
> >> Sent: Thursday, January 06, 2011 10:47 PM
> >> To: Environmentally-preferable design, construction, building elements
> >> Subject: Re: [Greenbuilding] R20 window insulation?
> >>
> >> Yes, I apologize if this wasn't clear to start with.  I usually refer to
> >> them as insulated interior window shutters.
> >>
> >> Bob Waldrop
> >>
> >> ----- Original Message -----
> >> From: "Gennaro Brooks-Church" Wait a minute, those are not R20 windows.
> >> Those are R20 window covers!
> >>
> >> Gennaro Brooks-Church
> >>
> >> Cell: 1 347 244 3016 USA
> >> www.EcoBrooklyn.com
> >> 22 2nd St; Brooklyn, NY 11231
> >>
> >>
> >>
> >> _______________________________________________
> >> Greenbuilding mailing list
> >> to Send a Message to the list, use the email address
> >> Greenbuilding at bioenergylists.org
> >>
> >> to UNSUBSCRIBE or Change your List Settings use the web page
> >>
> http://lists.bioenergylists.org/mailman/listinfo/greenbuilding_lists.bioenergylists.org
> > _______________________________________________
> > Greenbuilding mailing list
> > to Send a Message to the list, use the email address
> > Greenbuilding at bioenergylists.org
> >
> > to UNSUBSCRIBE or Change your List Settings use the web page
> >
> http://lists.bioenergylists.org/mailman/listinfo/greenbuilding_lists.bioenergylists.org
> >
> 
> --
> Effective immediately, please use the following e-mail address to reach
> me: lynelle at lahamilton.com
> 
> _______________________________________________
> Greenbuilding mailing list
> to Send a Message to the list, use the email address
> Greenbuilding at bioenergylists.org
> 
> to UNSUBSCRIBE or Change your List Settings use the web page
> http://lists.bioenergylists.org/mailman/listinfo/greenbuilding_lists.bioenergylists.org