- Polycarbonate Storage,
Cutting & Install Guidelines:-----------------Back to Install Details
- Storage: Store in dry,
shaded and well ventilated areas. Supported, sloped stacking is
best. Store sheets in covered areas, but not under flexible PVC
- Sheet Orientation
Warning: Sheets may have the protective U.V.
absorbing surface on both sides, or one side UV and one side Drip Guardand. Sheets are covered with a thin plastic film and marked
with a sticker to designate exterior side or both sides UV. Prior to installation,
peel film off sheet and mark exterior side with a grease
- Sheet Expansion & Contraction:
Sheet will expand in hot weather and contract in cold. Figure
about 1/32" per foot for 100º of temperature change. For
small greenhouses, the impact is minimal. To avoid problems follow
guidelines for the Cap & Trim System. you choose.
Installation on a cold day with sheets touching, or jammed tight
against a wall, can create problems as the sheet expands. The
sheet will absorb some flexing, but best to follow our guidelines.
The greatest amount of expansion and contraction can occur in the
spring and fall. Cold nights and warm sunny days can result
in dramatic temperature swings. During these times the sheet may make
a creaking noise. Do not be alarmed, this is a normal effect of sheet movement as the polycarbonate expands or contracts
along the framing members. On orders of poly over ten feet you will be sent an email explaining a foam tape option to help deaden the noise. Sheets under 10 ft. are usually not an issue. Also, bronze, being a dark
color, will get warmer in the sun and it will be hotter under the panel, even though the light and solar transmission is less. Bronze also expands and contracts 30%
more than clear or white opal.
- Cutting: To cut sheet width, for angle cuts, 10, 16 & 25mm cuts and
whenever sheet is to slide into Aluminum U-Proflie use circular
saw with plywood blade or jig saw with fine tooth blade. This
produces clean, even cut. Cut sheet before taking off film, or
static charge attracts fine chips to channels. Shake sheet, vacuum
or blow out channels, removing chips prior to install.
Condensation moving through layers continues cleaning channels,
but get clean as possible. Leave film on sheet until ready to
install, remove in area without dust. 6 and 8mm sheets may be cut
to length with sharp utility knife. Clamp straight edge to sheet
with rubber tip spring clamps and use as cutting guide. Run blade
along guide a few times to achieve sufficient cut. Turn sheet
over, bend and cut along crease to separate. Cut is ok for
tolerance situations. If placing U-Profile on sheet best to cut
with a saw.
- Sheet Positioning:
Install polycarbonate sheets with channels running vertically on
walls, and with the slope on the roof (see
Positioning and Attachment).
- Aluminum Closure Tape:
Prior to polycarbonate installation close top edge of gable end
wall sheets with aluminum tape. This edge then gets covered with
the Corner Trim. On freestanding structures set blocking, or a
purlin, at top edge of roof sheets. Prior to install also close
top edge of roof sheets with tape. If using "nominal" 2 ft.
spacing a U-Profile and no blocking is an option. On lean-to
structures the top edge of sheet sits on a ledger board with a
beveled top. Aluminum tape must be used here as well. The
U-Profile would not allow the sheet to sit flat.
- Sheet Installation:
Refer to Cap & Trim System for
a graphic description of sheet and system
- Attachment: Fasten
screws and washers as shown in Cap & Trim System.
- Point Fastening: See
and Attachment for
guidelines on fastening through body of sheet. Basic rule of thumb
is position fasteners every 3-4 ft., along length, in center of
- Weep Holes: The lower
edge of the vertical and lower edge of the roof sheets must have a
provision that allows for moisture weepage. This can be achieved
by drilling 1/16" weep holes in U-Profile, every 12"
- Silicone Sealing:
Refer to Cap & Trim System for
placement of silicone. Use Dow 999-A Silicone available at
Sundance. Silicone should also be used at aluminum and flashing
- Cleaning: Clean with
warm, mild soapy water, such as dish soap. If any dirt remains, wipe with soft cloth. Do
not scrub, scrape or use solvents. Rinse and dry with soft cloth.
Cleaning will extend sheet life.
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