Installation Tips & Tricks

"In-use" Moisture Content

Differences of more than 4% between the expected in-use average moisture content of flooring and the in-use average moisture content of underfloor construction are likely to cause problems such as cupping. The greater the difference the more severe the problems. A significant difference of 8% or more may result in buckling of the floor when the underfloor is the higher moisture content.
Finishing should proceed 1-3 weeks after installation is completed. Longer periods of exposure to job site conditions can result in future problems. Finishing immediately after installation does not allow the flooring adequate time to acclimate to its new environment.


Work from left to right

In laying strip flooring you'll find it easier to work from your left to your right. Left is determined by having your back to the wall where the starting course is laid. When necessary to cut a strip to fit to the right wall, use a strip long enough so the cut-off piece is 8" or longer and start the next course on the left wall with this piece.

Short pieces

For best appearance always use long flooring strips at entrances and doorways. Incorporate as many short pieces as possible at random in the floor. Do not group them in one area.

Put a "frame" around obstructions

You can give a much more professional and finished look to a strip flooring installation if you "frame" hearths and other obstructions, using mitered joints at the corners.

Reversing direction of strip flooring

Sometimes it's necessary to reverse the direction of the flooring to extend it into a closet or hallway. To do this, join groove edge to groove edge, using a slip tongue available from flooring distributors. Glue slip tongue in place and blind nail that edge. Proceed in the opposite direction nailing in the conventional manner.


Use only sound, straight boards for subfloors

The quality of the subflooring will affect the finished flooring. Use only square edge 3/4" dressed boards no wider than 6". Boards which have been used for concrete form work are often warped and damp and should not be used.

Don't pour concrete after flooring is installed

Concrete basement floors are sometimes poured after hardwood flooring has been installed. However, many gallons of water from drying concrete are evaporated into the house atmosphere where it may be absorbed by hardwood flooring and other wood components. This is not a recommended building practice since excessive moisture will cause problems with wood floors and other woodwork. Wood flooring should not be installed until after all concrete and plaster work are completed and dry.

Doorways, Stair Treads, and High Traffic Areas

If flooring direction changes, always use slip tongues or engage the flooring end matching into groove side of flooring to prevent movement and give a solid transition.

Put voids between screeds to good use

Masonry insulation fill, normally used in hollow concrete blocks, can be poured between the screeds of a slab installation to give additional moisture protection and deaden the drumming sound that sometimes occurs from foot traffic.

Sound deadening in multi-story building

Noise transmission from an upper to a lower floor can be reduced. Nail subfloor to the joists in the normal manner and cover this with 1/2" or thicker cork or insulation board laid in mastic. Cover this with another 3/4" plywood subfloor also laid in mastic. Nail the finish strip or plank floor to the plywood, or lay block or parquetry floors in mastic on the plywood. In the case of parquet the second subfloor plywood can be 1/2" tongue-and-groove type. Note that specifications for some high-rise apartment buildings call for other types of sound-deadening construction.

Mastics and trowels

There are several types of mastics available that are satisfactory for use in laying hardwood floors. Hot asphalt* is generally used only for laying screeds on concrete and the screeds must be positioned immediately on pouring the mastic. Cutback asphalt, chlorinated solvent and petroleum-based solvent mastics are all applied cold and are used for laying tongue and grooved block and parquet floors. Cut back asphalt mastic can be used to hold a recommended vapor retarder and/or to glue a plywood subfloor to the slab. Follow manufacturers' instructions on coverage, drying time and ventilation.

Trowels usually have both straight and notched edges. The notched edge is for use where a correct mastic thickness is specified. Both mastic and trowels may be available from flooring manufacturers and distributors.

Different Manufacturers Products

Do not randomly mix different manufacturers' products. Use transition areas such as doorways to separate the different manufacturers.