Hardwood Flooring Subfloor Systems, Choose The Right Type

Hardwood Flooring Subfloor Systems, Choose The Right Type

Choosing The Right Hardwood Flooring Subfloor

Choosing and installing a hardwood flooring subfloor over concrete areas.

Choosing the right system is important in how long, your hard wood floor will stay problem free. Because we’re directly on the ground, hard wood flooring are much more vulnerable to moisture, that can damage them.

Which type of subfloor system to use will depend on how much ceiling height restriction you may have, how much moisture you have, how flat and level are your concrete surface. Using the right system will save you from future headaches from repairing your hardwood floors.

Here are information to help you choose the right hard wood flooring subfloor for your home.

Minimum Requirement

Following manufacture’s suggestion for a hardwood flooring subfloor.

Flooring companies suggest the minimum requirements for a subfloor, to have your hard wood floors installed on. They suggest minimum requirement to save you money.

Their requirements are: 6mil plastic and 3/4 plywood, fastened with concrete nails.

Although it’s the most economical system, it’s not the best one.

If, you’re considering on using this subfloor system.

Here are things you should consider, also.

1. Fill in low spots with Henry’s subfloor skim coat. Let’s get the surface as flat as possible, eliminate waves and irregular areas. This will make your floors look and feel better.

2. Extend your plastic vapor barrier up and behind your baseboards by 1″. This will keep water vapors along the walls and away from your floors. Gaps and cupping are less noticable with baseboards.

3. Duct tape your plastic vapor barrier seams. Seal them tight, to stop water vapors from creating mold and mildew under your floor. You and your family will be able to enjoy your new hardwood floors without becoming ill.

4. Consider using fasteners that has an adhesive coating. These will reduce vapor from traveling up in the nailed areas. Prevent vapor from damaging your new hardwood floors. We don’t want to throw money away.

5. Use 1 1/2″ flooring staples and finished nails. this way the fasteners don’t break through the bottom surface of your hardwood flooring subfloor. Longer fasteners can cause the subfloor to come loose. creating a labor intensive repair. Spend more time enjoying your home and less time working on it.

6. Use 3/4 Advantech plywood sheathing for you hardwood flooring subfloor system. This type has good nail holding power and is great with moisture repellant. The more vapor protection the better. This prevent problems with you hardwood flooring

7. Use 30lb fortifiber hardwood flooring underlayment. We want to protect our hard wood floors from moisture, so thicker is better. It’s only $10 dollars more than red rosin paper and has moisture repellant. Extra moisture protection added to your wood floors. You won’t have to worry about your floors being wet.

If, you choose to use the minimum requirements for your hardwood flooring installation. Consider the above informations. To help you get a long lasting, problem free out hardwood flooring subfloor system.

Floating Subfloor

If, there is no ceiling height restriction. I recommend using a floating hardwood flooring subfloor system. This subfloor system is 1 1/2″ thick and does not require you to fasten it, into your concrete slab. Which reduces the amount of vapor coming from your concrete floor.

This system is easy to install you’ll be able to save energy to install your hardwood floors and there’s no need to fill low spots, up to a 1/2 inch variation.

Materials needed to install this hardwood flooring subfloor system are:

6mil pastic

Duct tape

Masking tape

4×8 1/2 foam insulation panel with thermal foil backing

Foil thermal tape

Liquid nail

4×8 1/2 plywood sheathing (2 layers)

1 1/2 coarse wood screws

1. layout your 6mil plastic, run 6-8 inch up your walls, we’ll trim any extras off later. Tape in place with masking tape.

2. Place the insulation panel over the plastic vapor barrier. Stagger all joints. allow a 1/4″ expansion gap, tape joints with thermal tape.

3. Apply a 3 inch dob of glue 16inch apart. Glue your first layer of 1/2 plywood on top of the foam panels, staggering the plywood joints to the foam panel joints.

4. Install the 2nd layer of 1/2 plywood on top. Stagger the joints of the top layer to the previous one. Fasten with 1 1/2 coarse wood screws. Trim off excess plastic. Then prepare for wood floor installation.

This hardwood flooring subfloor system will not only prevent vapor from damaging your hard wood floors, but will keep the cold away. and is an excellent choice of subfloor system for home theaters.

Using Sleepers and 3/4 Plywood Sheathing

Use this system if your concrete slab is excessively pitched, uneven, low amount of water may enter periodically, and you have no ceiling restrictions.

The advantage of using this system is you’ll have a perfectly flat and leveled floor. The subfloor is high enough to allow water to run underneath it, to get to a sump pump or weeping drain, keeping your home dry.

Materials needed to install this hardwood flooring subfloor system are:

6mil plastic

2x4x8 pressure treated lumber

3/4x4x8 tonue and groove Advantech plywood sheathing

1 1/2x 16inch foam insulation panels — use a high «R» rating

Liquid nail

3inch concrete fasteners with powder shot nail gun

2inch coarse wood screws


1. Cover the floor with 6 mil plastic, leave an extra 6-8 inch, tape on wall.

2. layout the floor frame, space the 2×4, 16 inch on center. Starting at the highest point. fasten this point down. Level and shim floor frame relative to this point. Fasten each point down, with concrete fasteners.

3. Cut and trim Insulation panel to fit in cavity area.

4. Apply a generous bead of liquid nail onto the floor frame. Install your plywood sheathing, fasten with 2inch screws. Trim off any extra plastic sheathing. Prepare for hardwood floor installation.

With a perfectly flat and leveled floor, you don’t have to worry about furnitures falling over, you’ll use the space more often.

Consider sound proofing your floors, with Homosote Boards for a home theater room and installing radiant heating for extra comfort. These things will make a good room, great.

Use one of these hardwood flooring subfloor system so that your hardwood floors will last a long time to come. So that you can enjoy them and rather than, work on them.

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