FAQ

Quick Tips for Installation
Installing ONDURA Sheets On A New Structure.
On new buildings, ONDURA sheets install
either over purlins or over solid decking covered by
roofing felt. Over decking, simply follow these same
instructions making sure that decking is secure be-
fore nailing down sheets. We strongly recommend
solid decking for buildings with interior ceilings. If
installing over purlins, space purlins 24” (60cm) for
greater than 15
o
slope and space purlins 18” (45cm)
for a slope between 10
o
-15
o
.
CAUTION: Avoid installation when the
material temperature is below 32
 F (0°C).
Re-Roofing With ONDURA Sheets.
ONDURA works well as a new roof over an
old asphalt shingle roof. Over roofs with a uniform
surface, just install sheets using nails long enough to
penetrate 1" (2.54cm) into supports of the decking
beneath. Over corrugated metal or other irregular
roofs, first install nailer strips using lumber spaced
appropriately for the slope of the roof, then lay
ONDURA sheets per instructions. Be sure that nail-
ing strips are securely in place.
Drive Nails Correctly.
CAUTION: Use only genuine ONDURA
nails for installing sheets and tiles. Other types of
nails may not provide sufficient hold-down strength.
Drive ONDURA nails only through the top
of corrugations. Always drive nails perpendicular
into purlins-not at an angle-so the rubber washer is
snugly in contact with the sheet. See Fig. 1. Do not
overdrive or underdrive nails. Slight hand pressure
on a nailed-down corrugation should not separate the
sheet from washer contact.
Fig. 1
Yes No No
Installing The First Sheet.
1. From the corner where
the eave and rake meet,
measure along the eave 48
inches (122cm) and mark.
2. From the corner of the
rake and the ridge, measure
along the ridge 48 inches
(122cm) and mark.
3. Snap a chalk line con-
necting these marks for sheet
alignment.
Fig. 3
4. Starting at the eave/rake corner, fasten the rake
corrugation of the first sheet at each purlin along the
rake (see Fig. 3 for Nailing Pattern).
5. Now align the opposite edge of the sheet with the
chalk line. Nail in place along the second corruga-
tion from the chalk line to allow for the side lap of
the next sheet. Be sure to install closure strip before
nailing eave.
Finishing The First Row Of Sheets.
You can now install the remainder of the
first row.
1. From the first chalk line, mark off successive 44
inch (112 cm) spaces along the eave. Do the same at
the ridge. (This 44 inch /122cm distance allows for a
1 corrugation side lap.)
2. Snap chalk lines between the eave and ridge
marks for sheet alignment.
3. Noting the nailing pattern in Figure 3, install the
rest of the eave row.
Edges with X’s are not nailed
down until lapped by adjoining
sheets.
Walking On ONDURA Sheets.
When walking on nailed-down ONDURA
sheets, walk on top of purlins only placing feet
across corrugations. Also wear soft-soled shoes.
ONDURA is more pliable in hot weather
and less pliable in cold weather. Always use care
when walking on ONDURA or any other roof.
Pulling Nails From Sheets.
To pull a nail from sheet, use a claw ham-
mer and a 1-1/2" (3,81cm) wood dowel or pipe. Put
the dowel or pipe in the valley of the corrugation
next to the crown with the nail to be pulled. Then
use the dowel or pipe as a leverage point for pulling
the nail. See Fig. 2.
Fig. 2