There is no fastening the underlayment to the subfloor. However, during installation some installers like to fasten underlayment to the subfloor to prevent the underlayment from moving. If your choose this route, staples are a good choice to fasten the underlayment.
It needs to be stapled or it will shift under carpet. Staples allow it a little give without shifting too much. Glue it and the underlay will wear out far faster than the carpet.
Many roofers will tell you that staples are fine for installing the synthetic underlayment. Others will tell you that cap nails are more effective. Both options often depend on the slope of the roof itself. Cap nails are typically made of steel and feature a plastic cap to prevent roof leaks, hence their name.
Do not lay out and fasten the whole floor! Fit panels into place first before fastening. Fasten the underlayment with either staples or nails. Start on one corner of the panel and fasten the 8' edge first, spacing 2” along the entire edge.
You can use decking screws as they are properly coated to prevent rusting. Do not select a fastener that is uncoated, cement or rosin coated, as they may rust and discolor your finished floor. The length of the selected fastener should be a minimum of 5/8″.
Floating Underlayment
Most flooring underlayment is installed floating on top of your subfloor. Installers usually lay the underlayment on the floor and start installing the laminate flooring on top. There is no fastening the underlayment to the subfloor.
Ring-shank and spiral-shank nails are the best fasteners for this application because they are grooved to increase friction and resist withdrawal. In fact, studies at Clemson University in South Carolina have shown that these nails have as much as twice the holding capacity of smooth-shank nails and staples.
Secure rows by taping them together, this will keep your underlayment in place.
Fasten the 8' edge first at 2" on center - 1/2" from edge - starting from the corner of the room. Leave an expansion joint of 1/8" to 1/4" between the panel and the edge of the walls. Stand on the panel to ensure flush contact with the structural subfloor, and do not overdrive the fasteners.
Underlayment sheets should be screwed in so that they are touching or slightly apart by only about 1/8 inch.
Yes, you must put a staple or screw in every “X”. The minimum spacing requirement is every 4” on center in the body of the panel and every 2” along the panel perimeter to properly secure SurePly® panels to the subfloor.
Staples Size 9mm
Rapid 9mm Staples box of 5,000 for stapling of underlays, felt paper and some carpets using a rapid stapler...
Some roofers prefer to attach felt underlayment with one-inch roofing nails ,or special nails with plastic washers, but most codes allow staples, which are easier to drive.
Each piece of underlay should be laid side by side, with the edges butting up against each other but without overlapping, as this can create an uneven surface for the laminate. Remember to tape the seams together with underlay tape to keep the pieces securely in place and prevent any moisture from seeping through.
If there is no shiny surface, one side usually features a thin backing material secured by what looks like mesh. This should face up into the room, in contact with the carpet. The rubber or foam side should face down towards the subfloor.
However, be aware that extremely thick underlays aren't best suited to high-traffic areas such as stairs and hallways. For these spaces we would recommend a medium thickness product with a high density rating. That said, you'll never regret picking a thick underlay for your lounge or bedroom.
You can fasten your plywood underlayment using one of the following: galvanized, coated chisel-point staples with a 1/4" maximum crown; galvanized, coated ring shank underlayment nails with a 3/16" diameter head; or flathead wood screws treated with a moisture-resistant coating (such as galvanized or zinc).
The nailing schedule will vary with the thickness of the underlayment, so refer to an underlayment nailing schedule chart to get the right schedule for your job. For example, ¼-inch underlayment calls for 3d ring-shank nails every 3 inches along the edge and every 6 inches within the field of the underlayment.
Answer. If the underlayment is 1/4" or 3/8" the staples are 1 1/8" long and should extend at least 85% into the sub-floor, but not into the joists. These are chisel point narrow crown staples used with an 18 gauge air nailer. Otherwise use 1 1/4" ring nails.
Stick your underlay to your subfloor – use adhesive glue or staples to make sure that your underlay is firmly attached to your subfloor. Lay your carpet on top – Now you can have your carpet fitted on top. Remember that caring for your carpet is the most important way to look after your flooring and your underlay.
More is not always better, and with underlayment, too much can compromise the integrity of your floor's locking system. Adding additional underlayment under vinyl with an attached pad can create too much cushioning, which causes the floor to come apart through use over time.
Felt underlayment should overlap the edge metal at the eaves and be overlapped by edge metal on the rakes. This is also true for rubberized asphalt underlayment, but not necessarily true for synthetics. Asphalt-saturated felt may fail for a number of reasons.
(3) Fasteners for 5-ply plywood Underlayment panels, and for panels greater than 1/2 inch thick, may be spaced 6 inches on center at edges and 12 inches on center each way intermediate.
No subfloor is perfectly level, but any signs of unevenness and high or low spots must be remedied. Please follow these requirements: Subfloor unevenness cannot be greater than 3/16 of an inch over a 10-foot span or 1/8 inch over a 6-foot span. Subfloors must not slope more than ½ inch per 6 feet (25 mm per 1.8 m)
Other factors like type, sound ratings, and density matter just as much, if not more than the thickness. With that being said, most underlayments are 2-3mm thick, but are sometimes thicker for carpet or to smooth out an uneven subfloor.