The following information is to help you familiarize yourself with the Technical Aspects of our Trade which relate specifically to installation and moisture. If you do have further enquiries, please feel free to contact our professional consultants by e-mail to info@wcfloors.com.

What hardwood flooring is available for above, on, and below grade?
Can I install a solid wood floor over a concrete slab?
What wood floor can I install over a concrete slab?
Can we install a hardwood floor over an existing vinyl floor?
What to I do to remove scratches in my wood floor?
Can I install a hardwood floor if I have pets?
Can an engineered wood floor be refinished?
Can I use throw rugs on my hardwood floor?
How do we stop a wood floor from gapping?
What should I use under furniture legs?
How do I acclimate my hardwood floor?
What is the difference between your pre-finished and unfinished flooring?
Can we install hardwood flooring in the basement?
What is the moisture content of our hardwood floors?
Do I need a moisture barrier if it is above grade?
Can I apply a wax finish to my pre-finished floors?
When ordering hardwood flooring how much extra should I order to allow for waste?
What is the most durable hardwood floor available?
Can I install hardwood flooring in a bathroom?
What are the benefits of hardwood flooring?
How should the hardwood floor be protected during construction?
What is the effect of moisture on hardwood flooring?
How does moisture find the hardwood?
How can we avoid potential moisture problems with hardwood flooring?
What is the best way to expedite the drying process?
What special considerations are there if the hardwood is to be laid over a crawl space?
Can solid wood flooring be installed over radiant heat?
How important is the choice of hardwood to be installed over radiant heat?

What hardwood flooring is available for above, on, and below grade?

Above grade - No restrictions
On grade - Solid wood flooring, Laminated (engineered) glue-down and floating
Below Grade: we recommend engineered glue-down or engineered floating floors.

Can I install a solid wood floor over a concrete slab?

It is not recommended to install solid wood flooring over a concrete slab. Although this is the general rule, there have been successful installations of solid wood flooring installed over dry, concrete slabs. This entails several additional steps. A plastic barrier is set over the slab and taped at all seams. Then some sort of moisture-resistant wood subfloor (marine plywood) is built on top of the plastic film. Then the flooring is nailed to the wood subfloor. If you decide to take the chance be sure to consult with the manufacturer as to their recommendations. Be aware, you may be voiding your warranty.

There is a new synthetic underlayment product on the market (called Sika AcouBond) that may allow for installing solid wood flooring over a dry slab. Check with the manufacturer of the wood floor to see if they will warranty this type of installation and what their recommended installation procedures are for this type of installation.

What wood floor can I install over a concrete slab?

With the improvements in hardwood floors most engineered and longstrip engineered plank floors can be used over a concrete slab. Manufacturers do not recommend using solid wood floors over a slab. Engineered planks and strip wood floors can be glued directly to a clean, dry, well-cured concrete slab. Some engineered wood floors can be glued at the tongue and grooves and then allowed to be floated over a special padding that is laid over the concrete slab. Longstrip engineered planks can be floated over the slab with a padding underneath. There are some new "hybrid" engineered floors that can be floated over a concrete slab and come with a click (glueless) tongue and groove locking system.

Note: New concrete slabs need to be fully cured for a least 60 days. All wood planks should be acclimated for 24- 48 hours prior to installation. Be sure to read and follow the manufacturer's recommended installation procedures.

Can we install a hardwood floor over an existing vinyl floor?

Yes and no. Is the vinyl flooring is tightly secured to the subfloor? Does the vinyl flooring have a thick cushion attached? If the vinyl floor is thin and well secured to the subfloor you may be able to float a wood floor over it. In some situations you may be able nail/staple a wood floor over it also. If the wood subfloor is sound you may be able to nail a solid wood floor over the top. Be sure to get the manufacturer's installation procedures for going over an existing vinyl floor and be sure to check if this type installation is warranted by the manufacturer.

What to I do to remove scratches in my wood floor?

This really depends on the type of wood floor you have, the finish you have and how deep the scratches are in the top layer. For small minor scratches in a urethane finish you should be able to order a touch-up kit from the store you purchased the flooring from. Be sure to use the manufacturer's recommended finish products and test first by applying a small amount in an out of the way area. For deep scratches you will probably have to have a professional do a screen and recoat. This is where they use special sanding screens to lightly abrade the floor's finish to help the new urethane bond better to the existing finish. With some wood floors you may be able to just replace the damaged boards. It is best to leave the sand and recoat, or board replacement to a professional flooring installer, or refinisher.

Can I install a hardwood floor if I have pets?

Although many homeowners have pets, hardwood flooring is not designed for the abuse a dog or cat can cause on a floor. Urine may permanently discolor the finish of the wood floor and large dogs' claws will probably leave scratches in the finish. The type of wood floor you buy, the color and the finish will also be factor in how much punishment the floor's finish can withstand before showing scratches and excessive wear.

Can an engineered wood floor be refinished?

Some of the better quality engineered wood floors have a 1/8" thick finish layer and can be sanded and refinished 1 or maybe 2 times. The sanding and refinishing of an engineered wood floor is best done by an experienced hardwood flooring refinisher. If you have heat vents in your floor you can remove a heat cover to get a side view of your wood floor. This will help you check to see how thick you finish layer is. Always consult with the manufacturer to see if the recommend sanding and refinishing of the engineered wood floors.

Can I use throw rugs on my hardwood floor?

Before using any throw rugs on your wood floor you should know the type of finish you have on the floor. All rugs should be non-staining, meaning the colored dyes will not bleed. Generally in the presence of moisture, some dyes used in rugs may bleed through onto your floor and discolor the wood floors surface. Also, be sure the rug does not have a rough backing material that may scratch the surface of the floor. Clean dirt and debris from under the rug regularly. To prevent possible shading of the wood underneath the rug, move the rug occasionally.

How do we stop a wood floor from gapping?

Gapping in solid wood floors cannot be stopped completely. Wood expands and contracts with changes in humidity. Using a humidifier during the heating months may help reduce the amount of gapping in solid wood floors. Also, some wood species may gap expand and contract less than others. Engineered wood floors are much more dimensionally stable than solid wood floors and will show little or no gaps between planks.

What should I use under furniture legs?

Most flooring stores carry the recommended felt pads for using under chair legs and other furniture. The felt pads come in various sizes. Some pads just stick on the bottom of the legs and others need to be nailed on. Never hit the pads directly with a hammer. Follow the directions provided with the pads. Check and clean the pads often to prevent debris, dirt and small particles from being trapped in the pad, which may cause scratches in the wood floor's finish.

How do I acclimate my hardwood floor?

Let the flooring acclimate for 5 to7 days, with boxes opened and laid flat in the room where the flooring is to be installed. If you are in an area with high humidity, you may need to install some humidity controls like a humidifier or dehumidifier.

What is the difference between your prefinished and unfinished flooring?

The prefinished hardwood floor is end matched with a tight micro-beveled edge, and has up to 10 coats of aluminum oxide finish. The unfinished floors come end matched with a square edge and must be finished on site. Both floors come with a 25-year structural warranty.

Can we install hardwood flooring in the basement?

No. It is highly recommended that you do not install hardwood flooring below grade. However, it is possible to install laminate flooring or engineered hardwood floors in these situations. Call a WC FLoors at 908-399-4408 to discuss some of these options available to you.

What is the moisture content of our hardwood floors?

Our hardwood floors are kiln dried to a moisture content of between 6 and 9 percent. Hardwood floors will naturally expand and contract with fluctuations in temperature and humidity. However, hardwood floors perform best when they are within a temperature/humidity range of 6 to 9 percent. At this range, expansion and contraction can be reduced to its minimum.

I need a moisture barrier if it is above grade?

Do Yes. We recommend using a vapor barrier of 15-pound felt paper. This vapor barrier should be laid between the hardwood flooring and the wood subfloor to prevent any moisture from getting to the floor.

Can I apply a wax finish to my prefinished floors?

You should never apply wax finish to your surface type finishes.

When ordering hardwood flooring how much extra should I order to allow for waste?

As a rule of thumb, add 7% to 10% for waste and cuts depending on your skill level and the layout of the area.

What is the most durable hardwood floor available?

Our hardwood floors are treated with up to 10 coats of an aluminum oxide finish. While this will certainly help the durability of the floor, it is the hardness of the floor that will give the best indication of durability. Refer to the Janka Hardness rating for a true indication of hardness for a selected species:

Can I install hardwood flooring in a bathroom?

Hardwood floors are not covered by warranty if installed in a bathroom. Moisture can cause damage to hardwood flooring.

Where can I install hardwood flooring?

Hardwood flooring is an extremely durable flooring product. It can be installed in virtually any room of your home that is above ground. There are several locations that are not recommended for hardwood flooring. Because hardwood flooring is a natural flooring product it is not recommended that it be installed in wet locations such as bathrooms, washrooms, saunas, enclosed porches or verandas, or anywhere that may require wet-mopping. Extended exposure to moisture of this type may cause your hardwood flooring to warp, swell or crack. Please note that certain species of hardwood are softer than others. You should consider using these harder species for high traffic areas. Refer to the Janka Hardness rating for an indication of the species hardness.

What are the benefits of hardwood flooring?

Hardwood flooring is one of the most popular types of residential flooring. Here are a few reasons why you should choose a hardwood floor:

• Solid hardwood offers a variety of grain patterns, natural color variations, and the beauty of a natural material
• Hardwood floors are easy to clean.
• Hardwood floors are ideal for allergy sufferers as they do not promote dust or harbor dust mites.
• Hardwood flooring is longest-lasting. Although there is a 25-year structural warranty on our hardwood floors , many hardwood floors last for decades longer.

How should the hardwood floor be protected during construction?

Consider the type of covering material you use as protection while other trades work on the floor.

Be especially aware of radiant heat. Any thick protective covering, such as plywood or Gyproc, will insulate the floor, causing it to overheat. The resulting damage can be difficult and expensive to repair.

Prefinished floors can be damaged beyond repair in these conditions.

Builders paper, laid throughout the hardwood areas, is recommended. DO NOT tape the paper to fresh finish, as you may damage the finish. Overlap the seams and tape the paper to itself. Always cover the floor wall to wall.

What is the effect of moisture on hardwood flooring?

Hardwood flooring should be delivered to site kiln dried at between 6 and 8% moisture content. Your subfloor should be within 4% moisture content of the hardwood flooring. Plywood is usually at 12% when purchased from a warehouse that protects its inventory from the elements (Always check that the plywood you are buying is dry). If for example you install the Hardwood Flooring at 8% moisture content over a plywood subfloor that is 14% it is likely that the hardwood will cup (see diagram below).

The diagram shows moisture migrating through plywood and into hardwood. The hardwood swells at the bottom first which changes the shape of the boards (cupping). Moisture can be removed by drying the surrounding environment and allowing the flooring a chance to flatten out. Only when the plywood, hardwood and surrounding spaces test dry should sanding be considered.

It does not take much moisture to make the floor cup significantly, for example: If you hold the prongs of a moisture meter to the skin of your hand the meter will register approximately 28% (Remember, with hardwood at 8% and plywood at 14% the floor will cup).

Sleepers are subject to the same rules. Concrete must also be tested to confirm the slab's moisture levels are within 4% of the Hardwood Flooring. Concrete dries, under good drying conditions, at an approximate rate of 1" per month (no radiant heat). If the slab is 4" , or more, thick the dry time will slow down.

Numbers mentioned are approximate and may vary from site to site. This information is a guideline only.

How can moisture find the hardwood?

Moisture from drywall mudding, painting, wet sheathing and wet studs etc. will always migrate to drier materials.

For example, from an unheated crawl space, moisture will quickly absorb into dryer plywood, pass through it and occupy the next driest material which is usually hardwood.

The hardwood will be the first, and likely the only, material to visually show the signs of migrating moisture.

The best way to tackle moisture problems is to plan ahead and take the necessary precautions and tests to ensure the correct site conditions exist before flooring is delivered to site.

Testing accurately for moisture can only be done using good quality testing equipment.

How can we avoid potential moisture problems with hardwood flooring?

Moisture problems are not easy to rectify and in many cases the best solution is to do nothing and allow the floor to settle naturally. The best way to tackle moisture problems is to plan ahead and take the necessary precautions and tests to ensure the correct site conditions exist before flooring is delivered to site.

Testing accurately for moisture can only be done using good quality testing equipment.

What is the best way to expedite the drying process?

1. Seal off the wet area
2. Use electrical heat (not propane heat)
3. Use low level air blowers
4. Use dehumidifiers

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