Laminated Flooring Installation Tips

When investing in a new floating laminate floor or any other flooring one should take precaution to assure that the floor will not only look great but also perform great. Here are a few tips on laminate flooring installation that will assist you in achieving your goals.

While the requirement of one manufacturer may differ from another the following information is common to many manufacturers. When purchasing a floor always obtain and read the installation instructions for the floor you are purchasing. The instructions for most laminate manufacturers may be found by clicking here.

Unfortunately as flooring inspectors we see many installations where the person installing the floor claimed to be an expert but did not install the floor as required by the manufacturer. Failing to follow the manufacturers installation instructions is a huge laminate floor problem as it often voids the warranty.

Subfloor Requirements of a floating floor

Concrete

• Perform a mat test to check for moisture. If any indication of a high moisture content perform a calcium chloride test.  Moisture content should not exceed 2.5% on a dry weight basis or the floor may fail.
• New concrete needs to cure for a minimum of 60 days.
• Use an approved vapor barrier.  Most companies require a vapor barrier even when the floor is covered by vinyl, linoleum, tile or sheet flooring.

Vinyl & Linoleum Subfloor

• Usually you can install over these if they are clean and level.

Wall-to-Wall Carpeting

• This is the one floor that most floating floors cannot be installed over and it needs to be removed unless approved by the manufacturer.  If the carpet is glue down be sure to thoroughly clean the surface of glue residues.

Ceramic Tile and Stone Subfloor

• These will normally not require removal but they must be leveled to within 5 mm in a 3 m radius.  A vapor barrier may be required, particularly over concrete.

Hardwood Subfloor

• Test for moisture content, it must be stable and between 6 and 10%.
• Correct the floor to eliminate any movement.  If the subfloor sags, inspect the joist below for twist or weakness.  If the subfloor is uneven or cupped at the joist, recheck the moisture making sure it is in the 6 – 10% range.
• Check for excessive moisture in the crawl space or basement including signs of potential water problems.
• Sand or plane high areas and patch or fill low areas with an appropriate leveling compound, or cover with a rigid underlayment.
• Do not use a vapor barrier on top of wood floors.

Identification of Common Laminate Floor Problems

Concern	Identifying Characteristics	Possible Causes	Recommended Actions	Responsibility
Indentation Damage	Dent in floor with fracture marks in the plastic.	Impact to surface or dropped object	Repair with the approved filler or replace board	Consumer or installer
Indentation Manufacturing Voids	Dent in floor without fracture marks in plastic.	Missing paper, damaged core, will show as irregular shape depression.	Repair with the approved filler or replace board	Manufacturer or installer if a highly visible defect.
Scratches, Cuts	Scratches showed up after installation or cross between boards	Plastic toys, improper furniture protectors, dragging furniture, abrasive soil.	Replacement of scratched boards	Consumer, or installer if occurred during installation
Scratches Manufacturing	Scratches seen at time or following installation.  Do not cross boards, generally in straight line.  May repeat on multiple boards.	Scratching during manufacturing.	Replacement of scratched boards	Manufacturer, or installer if highly visible and installed anyway.
Scuffing	Dull, wide marks or scratch like areas.	Chairs with plastic castors, hard plastic toys	Take preventative action, replace scuffed boards	Consumer
Water Damage Bottom up	Warped floor, swelling at multiple seams in localized or large area	Water leaks, no vapor barrier on concrete	Replace	Consumer if leak Installer if no vapor barrier
Water Damage Top down	Swelling at both sides of seams, gaps in seams, voids in glue	Improper joining and/or gluing	Replace	Installer
Out of Rack	Boards not aligned parallel on both sides and ends, seen on floor from point on where misalignment started.	Failure to align and tightly join starter row.	Replace as needed	Installer
Out of Square	A floor that is out of square will affect alignment on out of square planks only and not entire area.	Milling	Replace as needed	Manufacturer
No Underlay Foam	Buckling	No foam results in gluing to the underlayment and floor is no longer floating	Replace	Installer
Concave Bowing	Center of the plank is lower in elevation than the edges in length or width.	Installed on wet subfloor. No moisture barrier. Improper acclimation. Water damage. Manufacturing defect	Wait 6 weeks after installation to inspect.  If in excess of tolerance, replace.	Installer if installed over wet floor, improper acclimation or no vapor barrier.  Consumer if water damage. Manufacturer
Convex Bowing	Center of the plank is higher in elevation than the edges in length and width.	Manufacturing related condition	Wait 6 weeks after installation to inspect. If in excess of tolerance replace.	Manufacturer
Delamination	Laminate not adhering to core. May appear as a bubble on plank surface, delamination on edge about width of tapping block.	Laminate moves, hollow sound, improperly used tapping block, swelling due to improper gluing	Plank or section replacement	Installer if not properly glued or installation damage.  Manufacturer if laminate not attached.
Proud Edges	Height difference between planks when installed	Milling	Assess on basis of size and number and if outside of acceptable range, replace as required.	Manufacturer, Installer if highly visible and floor should not have been installed.
Pattern Misaligned	Pattern no aligned on the core	Improper manufacturing alignment	Plank or section replacement	Manufacturer, installer if highly visible and should not have been installed.
Foggy Laminate	Milky appearance throughout plank	Manufacturing	Replace section or as needed.	Manufacturer
Sheen Variation	Sheen varies between planks with some dull and others shiny.  Usually light dependant	Manufacturing	Replace section or as needed.	Manufacturer
Color Variation	Plank varies in color from the true color or design	Manufacturing or mixed pattern	Plank or section replacement	Installer if wrong color or highly visible, otherwise manufacturer
Foreign matter under laminate	Particles under laminate that show up either as marks, spots or lumps.	Dust or debris during manufacturing.  Generally light dependent and not seen until after installation.	Replace as needed	Manufacturer, installer if highly visible as it should have been seen and not installed.
Improper Milling	Floor unlevel or not square in areas	Product out of square, defective tongue or groove.	Replace as needed	Manufacturer, installer if highly visible as it should have been seen and not installed.
Chattermarks (Cuttermarks)	Widthwise, wavy or rippled bands.  Not seen in all lighting.	Skips during sanding	Replace	Manufacturer, installer if highly visible as it should have been seen and not installed.

Vapor Barrier Under Laminate Floor and Crawl Space

Interior Vapor Barrier Over Concrete Subfloor

When a laminate floating floor is installed over a concrete subfloor a moisture barrier must be used.

Failure to install a proper vapor barrier over concrete will likely result in a floor expanding. This will cause laminate floor problems such as cupping and gaps.

Always check a manufacturers installation instructions prior to installation to assure that proper procedures are followed and proper materials are used.

Do Not Use a Vapor Barrier on Wood Sub Floors

It is important to note that you DO NOT install a vapor barrier over a wood subfloor. Over wood a vapor barrier will trap moisture and cause damage. Some laminate underlayments are a combination of vapor barrier and foam so take care in selection.

A foam or other type underlayment approved by the laminate manufacturer needs to be used for installation over wood subfloor.

Vapor Barrier in Crawl Space Requirement

Crawl  spaces must have a proper vapor barrier ground cover spread over the soil. A crawl space must also have proper cross ventilation and no dead air spaces. Without the appropriate vapor barrier and cross ventilation, crawl space moisture will attack the underside of a subfloor and the back of the laminate flooring core. Excessive crawl space moisture may result in cupping of the laminate floor.

Water Damage Laminate Floor

Water Damage to Laminate Flooring

Plumbing and Appliance Leaks

Water damage from plumbing and appliance leaks such as dishwashers, water heaters, washing machines and ice makers can result in buckling of a laminate floor. Often these leaks are very slow and go unnoticed.

Slow leaks are often difficult to identify as they are below the laminate where they penetrate into the laminates core material.

While you may not see the leak an inspector can tell that excess moisture is there by use of a moisture meter.

Flooding

Severe plumping leaks such as a pipe break or overflowing toilet will usually result in buckling of a laminate floor.

Water Damage to Laminate Floor From Concrete

Moisture can enter into the back of a laminate floor resulting in cupping. An entire floor may cup from a concrete floor that is too wet. This can occur even when a vapor barrier has been used below the laminate floor.

Testing for Moisture

All concrete floors should be tested for moisture prior to installation of the laminate floor covering.

Newly poured concrete should be allowed to cure for at least 60 days prior to installation of the laminate floor.

There are a number of ways to tests for moisture. Many of these such as electronic testing and calcium chloride testing should be performed by companies such as The Weinheimer Group LLC that have the proper training and equipment.

Easy Consumer or Installer Test for Concrete Moisture

Below is a test that can be used inexpensively, without training. This test is acceptable by many laminate flooring manufacturers.

Materials:

• 6 mil polyethylene film
• Duct tape.

Procedure:

• Using duct tape completely seal a 2′ x 2′ section of the polyethylene film down to an area of clean concrete. It is best to do this in several locations where the laminate floor is to be installed. At least one test per 500 square feet.
• After 72  hours remove the plastic. (one week is better)
• If the concrete is dark or wet below the plastic the subfloor is too wet to install a laminate floor.

Water Damage Maintenance and Pet Damage

• Spills and improper wet cleaning of a laminate floor can cause swelling at the laminate joints. This is often seen as puffy areas along the edge of the planks and frequently crosses between plank edges.
• The most common cause of  edge swelling over a large area is wet mopping or using popular floor cleaning equipment such as but not limited to the Swiffer Wet Jet.
• Sometimes it takes a year or two of use before maintenance related issues start to show up. Some floors may never experience noticeable damage by these cleaning methods and others will experience severe damage. Water damage is rarely covered by the laminate manufacturer.
• Spills and damage from pet urine are usually localized and show as swelled areas between planks. This is a site related condition and not a laminate floor problem and will almost never covered by a manufacturer warranty.

Sealant Around Laminate Edges

• Some laminate flooring manufacturers require a sealant to be used around objects such as sliding glass doors, kitchen cabinets, water hearers and in other areas prone to leaks and moisture.
• The proper sealant must be used to prevent lock in of the floor.
• The sealant must be properly applied or voids will be left for moisture to enter.
• Failure to use a sealant as specified by the laminate flooring manufacturer can void a warranty.