hen you are ready to begin, the following instructions apply to strip flooring laid on plywood-on-slab, on screeds, and plywood or board subfloors.
(NOTE: Flooring "SHORTS" - 11/4ft or 2ft bundles
of flooring strips are "Strip Flooring" and
should be installed as such.)
NOFMA does not recommend gluing Shorts directly to a slab.
With plywood or board subfloors, start by re-nailing
any loose areas and sweeping the subfloor clean. Mark
location of joists on perimeter walls so that starting runs
and finishing runs, which require face nailing, can be
nailed into joists. Then cover subfloor with a good grade
of 15 lb. asphalt felt/building paper, lapped 2in-4in along
the edge seams. This helps keep out dust, retards moisture
movement from below, and helps prevent squeaks
in dry seasons.
Direction of Finish Flooring.
Direction of finish flooring
should be at right angles to the joists as shown in
Fig. 4. This is generally the longest dimension of the
room or building and gives best appearance.
Begin flooring installation along the longest continuous
wall parallel to the flooring direction of most
rooms. (i.e. Down a long hallway wall.) Work from there
into the room. Use a slip-tongue to reverse direction
and complete the rooms. Glue and blind nail the slip
tongue. At any change of direction, always provide
tongue and groove engagement either with a slip
tongue, or factory edge or end.
Starting to lay the floor. Location and straight alignment
of the first course is important. Place a mark 3/4in plus the width
of flooring (3in for 2-1/4in flooring) on the end wall near a corner
of starting wall. (Figure 5.) Place similar mark at opposite
corner and insert nails into each mark. Pull string line between
nails. Nail the first strip with its leading edge on this line.
Nailing Schedule
NOFMA Certified wood flooring must be installed over a proper subfloor.
Tongue & groove flooring is blind nailed on the tongue edge with face nailing required on starting runs (1-2) and finishing runs (2-4). Square edge flooring is face nailed.
The gap between that strip and the wall is needed for expansion
space and will be hidden by the shoe mold (Fig. 1).
If you're working with screeds on slab make the same
measurements and stretch a line between nails. Remove
line after you get the starter board in place.
Lay the first strip along the starting string line, tongue
out, and drive 6d or 8d flooring nails or casing nails (galvanized
or screw shank hold best) 1in from the grooved
edge. Nails should be driven into the top surface of
strips and counter sunk (face nailing). Position nails
over supporting joists, and near ends of strips or into
each screed crossed. Keep the starter strip aligned with
the string line. (Pre-drilling nail holes will prevent splits.)
Also, blind nail starting strip through the tongue according
to nailing schedule.
Rack the floor. Lay out seven or eight rows of flooring
end to end in a staggered pattern with end joints
at least 6in apart. Find or cut pieces to fit within 1/2in of
the end wall. Watch your pattern for even distribution
of long and short pieces and to avoid clusters of
short boards (Fig. 6).
Nailing the floor. With plywood on slab construction
the face nails should be cut to slightly less than
11/2in. After the starter run fit each run of successive
strips snug, groove-to-tongue. Blind nail through the
tongue along the length of the strip according to the
schedule shown in the table above. Countersink all
nails. After the second or third run is in place you can
change from a hammer to a floor nailing machine
which drives nails mechanically or pneumatically, and
does not require additional countersinking. Various
floor nailing machines use either a barbed cleat or staples,
fed into the machine in clips. The nailing
machine drives fasteners through the tongue of the
flooring at the proper angle.
When using the floor nailing machine to fasten 3/4" thick
strip or plank flooring to plywood laid on a slab, be sure
to use a 11/2" cleat, not the usual 2" cleat which may come
out the back of the plywood and prevent nails from countersinking
properly and tearing the vapor retarder. In
all other applications the 2" cleat is preferred.
Continue installing across the room, ending up on the
far wall with the same 3/4in expansion space as on the beginning
wall. It may be necessary to rip a strip to fit. Avoid
nailing into a subfloor joint. Position flooring strips so
that they do not meet over subfloor joints. Blind nail by
hand where the nailing machine can not be used. Face
nail the last runs when unable to blind nail by hand.
With 21/4in strip face-nailing is required the last 2 or 3 runs
and in a ripped piece of a strip if one has been used. Use
an offset pry bar or lever device to tighten these last facenailed
runs all at once before face-nailing.
Nailing to screeds. When nailing direct to screeds
(no solid subfloor), nail at all screed intersections and
to both screeds where a strip passes over a lapped
screed joint. Since flooring ends are tongue and
grooved, all end joints do not need to meet over screeds
but end joints of adjacent rows should not break over
the same void between screeds.
Some boards may not be straight. A large screwdriver,
sharpened pry bar, or wedges can force such boards
into position or pull two or three runs together.
Shoe molding. Nail this to the baseboard, not the flooring, after the entire floor is in place.
Flooring Installation Guide :: Index
1) Installation Introduction
2) Handling & Storage
3) Job Site Conditions
3.1) Installing over Concrete
3.2) Testing Concrete for Excessive Moisture
3.3) Concrete Slab Preparation Prior to Installation
4) Laying & Fastening
5) Plank Flooring
6) Laying a New Strip Floor Over an Old Floor
7) Parquet, Block Herringbone & Similar Flooring
8) Special Construction Situations
9) Tips for Easier & Better Flooring Installations
10) Strip Flooring on Walls & Ceilings
11) Installation of Gymnasium Floors over a Concrete Slab
Installation content courtesy of NOFMA. FloorMall.com is a Proud Member of NWFA.
