Hardwood Flooring
Hardwood Flooring

Hardwood Installation

Let’s spend a while talking hardwood floor installation for your Sacramento area home. I really want you to understand how important your research is in choosing an installer AND a specific material. This is an investment that should last a long time. I am going to cover the basics thoroughly and dispel a lot of myths at the same time. If you want to learn even more, I suggest you read my multi-part blog post series on hardwood floor failures and how to prevent them.

Four Wood Floor Factors For Consideration:

  • Density– Wood floors are derived from a variety of wood species and this means that they have varying degrees of density, which factors into durability.
  • Stability– Wood is a hygroscopic material and it is constantly able to either gain or lose moisture. Each flooring material has an associated dimensional change coefficient. Some species of wood floor such as Hickory are considerable affected by moisture changes in the home.
  • Board width-Wider boards can also impact how susceptible your wood floor is to moisture. If you hate cracks and gaps in your flooring, then this part of selecting a wood floor needs to be well factored.
  • Milling/Construction– In the wood flooring business I would certainly say that product quality is directly proportional to price. The process of taking a tree and making it into a floor requires expertise in kiln drying, molding the lumber, and proper chain of custody. If you are considering an engineered wood floor for stability reasons, then the glue and plywood layers used to construct the base of the material are very important. I cover this in a video here.


I have yet to hear one exact number of days that accurately encapsulates the necessary acclimation period for all wood floors. The climate in Sacramento can be different than even Auburn, CA near our shop, especially in winter. All of these are variables impacting floor performance. A properly acclimated wood floor has achieved Equilibrium Moisture Content (EMC), and is no longer gaining or losing moisture when the interior of your home is properly maintained. This timeline can vary greatly and requires proper training and knowledge to understand and implement. There are standards for wood floor acclimation that the NWFA recognizes:

  • Strip wood floors cannot vary by more than 4% moisture content relative to the subfloor of your home.
  • Plank wood floors (wider than 3”) cannot vary from the subflooring by more than 2% moisture content.

Relative Humidity (RH) is the single MOST overlooked component of floor acclimation by 95% of wood floor installers in my industry. Although its effects seem trivial to most, it is the slow cancer that creeps in and creates a moisture imbalance in wood floors. The result is either subtle cupping or gaps and cracks in the wood floor. In the Sacramento valley and Sierra foothills, the average RH inside your home can vary from 10%-50% depending on the season. Virtually every wood floor manufacturer will specify in their installation instructions that the RH in your home needs to be maintained between 30-50%. If you do not do this, then you WILL void your warranty. During my tenure as a wood floor inspector I have witnessed virtually every “cut rate” inspector use this exclusion to deny a lot of claims on failed products, particularly strand woven bamboo and engineered flooring. Check out my post “The 30-50 wood floor conundrum”.

Sacramento Moisture Content of Wood

Jobsite Preparation

Do you dislike squeaky floors? Most squeaks originate from either a loose subfloor or excessive up/down movement in a floor. Homes around the Sacramento region generally have either a wood subfloor or concrete.

If the home has a wood subfloor (Land Park, Citrus Heights, Granite Bay…) then the key is to properly secure any loose areas of the subfloor and flatten them. High spots in the floor need to be leveled. Sometimes these areas can be sanded, but on rare occasions we have removed the plywood and planed down the joists to get the area fixed properly. Any low spots in the floor can be corrected with floor leveler (in certain cases) or shimmed with an appropriate system.

Installing wood flooring in Sacramento over concrete subfloors requires good planning. Lower in the valley, some areas like Davis have a very high water table and can present challenges for mitigating moisture. Typically when a slab is poured, the concrete is poured over a plastic that prevents groundwater migration through the slab. This is not a guarantee and in some areas of the country there are even bacteria that can degrade the plastic underneath concrete slabs. Concrete is essentially a porous sponge that can always transmit moisture to the surface above. Taking a moisture reading of a concrete slab is essentially a snapshot of moisture at the moment. The most effective method is to use either a 2-part epoxy or a moisture-mitigating adhesive. Application of these systems per manufacturer guidelines is essential to avoid voiding your wood floor warranty. Aside from that, you will need to prepare the slab properly for level. Also consider that wood flooring installed over concrete does not have the same feel and can have a much more firm feel. If you want a softer feel underneath your floor, then you should consider systems like the Sika Acoustibond system that has a much softer feel.

Contractors can be impatient and often jump into installing hardwood flooring without any consideration of proper subfloor preparation. This is a big mistake that usually leads to long-term problems with a wood floor. You can have broken or chipped edges, squeaks, or premature finish wear from bad subfloor preparation.

It is important that if you are having a wood floor installed, that you alert the contractor to as many things you know about the floor that concern you. If your existing floor has high/low spots or makes squeaks share that information with them. The more you share your expectations of the project, the better your wood floor project will be.


Wood floors are installed with three general methods: nail-down, glued, or floating. All three wood floor installation types are common around Sacramento. Below are the two wood floor installation methods we offer.

Nail down wood floor installations use cleats or staples. Flooring manufacturers have a suggested fastener for installation listed in the instructions.

  • Staples have two entry points per fastener and can split more brittle flooring, such as Australian cypress.
  • Cleats are barbed and are more “gentle” to the flooring, as they only have one entry point.

Fastener schedule- All wood floors have a specific number of fasteners required per board and a required distance between the fasteners. Sometimes people get the idea that more is better and overnail a floor. The trouble is that it can very easily split the boards and result in a loose floor quickly.

Nail gun pressure- Fasteners need to go into flooring to a specific depth. Too little or too much can make the floor loose. The tongue and groove in the flooring need to interlock precisely.

Glue Down Installation requires use of the proper trowel with proper adhesive spread rate. All manufacturers require 100% transfer of the adhesive to the flooring to warrant the install. There are varying types of adhesives. Many wood floor adhesives offer some degree of moisture mitigation to protect the flooring. Some wood floor glue offers noise abatement properties. The most critical factor in glue down installation is ensuring that the concrete slab is properly sealed and free from high/low spots. If the concrete is not flat enough, then you could have loose boards or hollow spots.

Solid wood flooring that has a width that exceeds 5” typically should be glued and nailed. That is the general industry guideline and can vary between manufacturers.

If you live anywhere around the Sacramento region (Roseville, Folsom, Auburn, etc…) and you need a wood floor installed please contact us so we can have adequate time for planning your project. Acclimation us very important, especially if you want to install wide plank, long length wood flooring. Accuracy is everything and you may find it essential to have a conversation with your heating and air contractor to install a humidification system.