Making Green Houses

33 posts / 0 new
Last post
Michael_Rudmin's picture
Michael_Rudmin
Status: Platinum Member (Offline)
Joined: Jun 25 2014
Posts: 688
Securing acrylic

If securing acrylic is a problem, I would suggest mounting the acrylic in a wooden or metal frame, with a double-layered gasket of bubble wrap all around, sealed with silicone caulking if necessary.

The wood or metal can be screwed securely, and can be large enough to securely hold the acrylic. The bubble wrap gasket will prevent a concentrated load.

Krystof_Huang's picture
Krystof_Huang
Status: Member (Offline)
Joined: Jan 7 2017
Posts: 13
PPPS--correction of

PPPS--correction of correction--I guess it is 1-in poultry fencing I am using for roof or quasi-horizontal regions. 2-in will work and will allow more light but may be less likely to have insulation value.

For vertical areas I do not use poultry fencing, but instead use vinyl film--held down by battens made from ripping studs down to "2x2" = 1.5x1.5. Thus creating 1.5-in spaces between each vinyl film layer. Also, an extra vinyl film runs from top of one 2x2 to bottom of next 2x2. So effectively 2 air spaces are created with each layer of 2x2 battens. (R value maybe 2 per layer.) For strength, I do suggest chicken wire over the final layer, followed by polyethelene or vinyl. The outermost layer will be replaced much more often, thus I suggest the cheaper polyethene--and which also blocks more light so the inner layers will then last the longer. However if you want to impress your friends and family with something like a clear view then use vinyl.

The above "vertical" or "wall" method can also be used to super-insulate horizontal skylights. Skylights usually being relatively a small or limited surface area, chicken wire is not necessary and also would block too much light. So instead, use the 2x2 battens to create multiple air spaces. Oh and rip a 1/4-in thin batten down the center of each sklight for each batten layer. This enables you again to create 2 air spaces for each 1 batten layer. (I can post photos if anyone is interested. Note: no screws needed. Use Lexel to attach everything without making holes in the factory-made skylight.)

(Please note that Lexel caulk is "liquid Lexan" and is much more reliable and durable than "100% silicone" caulk--even though they may look similarly clear in the tube. Also note that under full sun, bubble wrap will deteriorate in a few years. Bubble wrap is thus not a sensible sealing material for acrylic panels which are costly and last for decades.)

If the skylight is fairly horizontal (shallow sloping roof) then in northern climates, one layer of chicken wire is needed under the topmost layer of 6mil vinyl--not for insulation but to prevent a possible snow load from stressing the vinyl film. But it will look much better and be worth it not to use chicken wire--but to spend $60 or so per skylight for thin rigid acrylic panels from Home Depot as the final layer--covered with one more layer of vinyl to prevent aging. In summer, be sure to put opaque plastic over the skylights--not only to reduce heat, but also for the vinyl to last much much longer. Crystal-clear "packing tape" can be used to hold the summer shading. For this temporary use, black plastic mulch or a black trash bag will do, although white plastic will look better and allow a nice bit of light. The ideal summer skylight covering is aluminized mylar "emergency blanket" or "space blanket" often sold for $1 each. This mirror-like ultra-thin mylar reflects all the heat while also allowing you to see out and a bit of light in, and can look impressive if just trimmed nicely with the scissors.

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
Login or Register to post comments