How to Install Laminate Floors

Laminate flooring is basically a photograph of wood embedded in composite panels and resin. The description isn't very appealing, but laminates continue to grow in popularity because the seriously synthetic composition is eclipsed by practical benefits.

Last week, we looked at a few of them, including a floating-floor installation that's possible over almost any material, a no-nailing, snap-together assembly, and a highly stain- and dent-resistant surface that requires no waxing or refinishing.

This week, we'll check into the details of a typical installation.

First, bear in mind that laminates are thin (in the half-inch range) and can't shore up a weak or heavily damaged floor. They will work well over sound floors that are cosmetically damaged, such as a worn oak strip flooring you can't stand to scrape, sand and seal yet again.

Also, laminates in plank or tile form come with different fastening systems. Some require glue in the joints; others lock together without glue. You need to follow the manufacturer's instructions, and be aware that using glue or other materials not specifically recommended by the manufacturer may void the warranty.

Overall floor quality depends on the product (mainly its thickness) and on the installation. Generally, though, glued floors are strongest and most water resistant. They also require the most work.

Basic layout and cutting are similar with glued and glueless systems, but gluing the joints takes more precision, patience and cleanup. Some manufacturers require a continuous bead along each seam, while others call for spot application at specific points along the joint. The latest innovation is a preglued joint that you dampen to activate while laying the floor.

With some glued systems, you also need special installation tools, such as ratchet straps, generally for rent by the supplier. Because laminates float over the subfloor, initial pieces aren't anchored the way they are with a nailed installation, such as three-quarter-inch strip oak.

In fact, you need to leave space for expansion, typically one-quarter-inch on all sides of the floor and around any fixed objects, such as radiator pipes and cabinets. As you add glued planks, there is no anchored piece to press against and tighten the joints. Instead, ratchet straps are used to draw together glued joints.

Glueless installations are generally not as strong and rely on a snap-together feature built into the tongue-in-groove joint. But without glue the job is easier, quicker and a more reasonable do-it-yourself project. And after the planks are connected, you can walk on the floor immediately.

A major manufacturer, Pergo, reports "most people can complete a 300-square-foot room over the course of a weekend." That's using their preglued planks or a glueless laminate that does not require adhesive application or ratchet straps.

Most laminate installations call for the same kind of site preparation, mainly that the subfloor be clean, dry and flat. You can check flatness with a straight 2-by-4 or other straightedge about six feet long. Depressions deeper than three-sixteenths of an inch must be filled and high spots ground or planed away.

Thin underlayment pads will bridge minor irregularities, but are designed mainly to cushion the laminate and reduce sound transmission. (Some planks come with underlayment attached.)

Manufacturers often require extra prep work in basements, potentially damp or wet areas and floors with radiant heat. They also may suggest a moisture test (according to their instructions) over any concrete slab. Even then, you should unpack materials and let them acclimate to the work space for at least 48 hours prior to installation.

Most installations look best (and are easiest to handle) with planks running parallel to the longest wall. But a perpendicular layout is fine, too, because laminates don't need to be nailed across floor joists. Starting at the longest, straightest, most visible wall usually makes sense.

Begin with a full plank, then create staggered joints by using a two-thirds-length plank to start the second row and a one-third-length plank to start the third.

Repeating the same stagger throughout can call attention to joints by creating a floor-wide pattern. Staggering planks more randomly helps the joints submerge into the hue and grain of the surface.

If you haven't installed a floor before, invest the time to make a partial dry layout to visualize the effects of different plank directions and joint patterns. This will also help you minimize waste and be sure before starting that you have the right type and amount of trim, such as matching quarter round to use over the expansion gaps at baseboards, and reducer strips to use where laminates join a floor of different thickness.

You can cut planks to length by hand, of course, and there is some leeway for rough cuts at room edges where expansion gaps have to be covered with trim. But the tools of choice are a radial-arm saw, chop saw or miter saw.

All allow you to position the plank securely against a guide fence and make controlled and accurate square cuts to length.

On thin, prefinished materials like laminates, it is best to use a carbide-tipped trim blade. On a 10-inch miter saw, for example, the blade should have 48 or more teeth. To cut around obstructions, you're likely to need a drill and a jigsaw fitted with a fine-toothed blade.

Mike McClintock
Special to The Washington Post
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