One of the great things about having a hardwood floor is that, even when it eventually starts to show its age by developing scratches and dings, you have the option of refinishing the material to revitalize the floor completely. This involves sanding down the surface past any finish or blemishes, reapplying color treatments, and sealing it with a top-coat finish. It will look like a new hardwood floor and can be achieved for a fraction of the price of a new installation.
Average Costs for Refinishing Hardwood Floors
Nationally, the average cost for refinishing a hardwood floor is $1,761, within a typical range of $1,074 to $2,486. But there's every chance your floor is anything but average, and your actual costs can vary depending on many factors, especially the availability and cost of labor in your area. On a per-square-foot basis, average costs run about $3 to $8 per square foot, but these costs can vary depending on the complexity of the work and the total size of the area you want to have refinished. Per-square-foot costs may be less if you're having a contractor come in to refinish an entire house, while costs can be more if they are refinishing just a single room.
The cost for refinishing wood stairs averages about $40 to $75 per stair tread. The high cost is because these are small surfaces that require skilled, time-consuming detail work.
For DIYers, the upright sander required to refinish a floor rents for about $60 per day or $250 per week—a full weeklong rental is not unreasonable if you are refinishing several floors. Upright sanders are available with belt-action or orbital-action heads. Belt-action sanders are regarded as more heavy-duty tools, but they can be hard to handle and beginners sometimes have problems with gouging the floor when using them. Orbital-action sanders are designed to remove the floor's finish only. They aren't capable of sanding past deep blemishes.
A heavy-duty disc sander, also called an edger, is also needed to sand into corners, edges and tight spots where the upright sanders can't reach. They cost slightly less per day to rent than the upright sanders.
Other than the sanders and sandpaper, the biggest additional DIY cost is the finish material. Polyurethane finish costs around $40 to $100 per gallon depending on the thickness of the finish and the quality of the product. One gallon of polyurethane is usually enough to apply two coats over a 300-square-foot space. Polyurethanes come in both water-based and oil-based (alkyd-based) forms. Some professionals swear by the results of oil-based products, but most DIYers find water-based finishes easier to use.
If New Flooring Is Needed
If extensive damage requires new flooring to be installed, you can expect prices to start at about $6 per square foot and run as high as $15 ($3 to $5 per square foot for the materials plus $3 to $10 extra for the installation labor).
Solid Hardwood vs. Engineered Hardwood Flooring
Hardwood flooring comes in two varieties: solid hardwood, which consists of the same wood from top to bottom, and engineered hardwood, a laminated product in which a relatively thin layer of solid hardwood is bonded over a layer of less expensive sheet material, usually plywood or some form of particleboard.
Engineered hardwood can still be sanded, but you'll need to take care not to grind down through the surface layer into the core. Generally, you'll be able to refinish engineered hardwood only once or twice before the core layers are exposed. By contrast, you can refinish most solid hardwood floors several times over the course of their life. However, eventually, even solid hardwood is going to wear down to the point where it's too thin to be sanded again safely.
Whether you try to refinish your hardwood floors yourself or have a professional contractor do it (often the better choice), the process will follow a logical sequence. There are four major labor parts of a hardwood refinishing project that need to be accounted for in any estimate.
Preparation: This involves getting the floor ready to be refinished and consists of repairing damaged areas, cleaning the floor thoroughly, and then ensuring that the surface is completely dry and free of dust and particles before proceeding. If the floor has deep stains, they may be treated individually before refinishing begins. Broken or missing boards will need to be replaced. Any protruding nail heads will be driven down below the surface of the wood. Most contractors will remove baseboard shoe moldings to allow sanding equipment to sand right up to the wall edges. The moldings are replaced after sanding and finishing are complete.
Sanding: This is the process of grinding the wood flooring surface down to below the level where any blemishes or treatments have penetrated. This work is usually done with an upright, walk-behind power sander fitted with a sanding disc or screen. Edgework is generally done with an edging sander or belt sander. The sanding work usually takes several passes with progressively finer sandpaper. After sanding, the floor is thoroughly vacuumed and cleaned. Be aware that some deep scratches or gouges may not be removable by traditional sanding. Your floor will look much better, but it may not be quite as pristine as a new installation.
Staining: Once the floor has been sanded down, it will resemble new untreated wood. Depending on the wood species, some people prefer to apply a surface finish directly over the bare wood. Or you can apply various dyes or stains to color the wood before applying a surface finish. Oil- or water-based wood stain is the standard material used for coloring, applied by rubbing it into the wood with cloths or staining pads.
Topcoating: The final step is to apply a tough, durable topcoat finish, usually a water- or oil-based polyurethane. The topcoat is applied with a brush and roller or finish pad, and it usually includes two or even three coats. Polyurethane finishes come in several different gloss finishes, from flat to high-sheen. The final coat may be buffed to increase its sheen and smoothness.
Factors Affecting Cost
In general, for a basic refinishing job, it will take a contractor about four to five hours per 100 square feet of space. A number of factors can affect the overall cost of refinishing:
Size of the floor: Generally, smaller rooms are going to be more expensive to refinish per square foot. This is because the equipment used to sand down a hardwood floor is usually quite large, and it is not easy to get it into or maneuver it through tight areas. Some small bathrooms, powder rooms, and laundry rooms may be too small to refinish at all without the help of a specialist with the necessary equipment. On the other hand, you can often get a discount on a project to refinish a larger space or multiple rooms on the same visit. Larger projects represent more money for less effort to contractors, and so they are usually willing to offer discounts to secure these jobs.
Local labor costs: In general, contracting companies located in large metropolitan areas are going to charge more for a hardwood refinishing project, mostly because the demand for their services is higher. There can also be a purely regional factor at work; for example, labor in the Northeast is often more expensive than it is in the South.
Company skill: Sometimes, you will be able to find companies offering hardwood refinishing services at extremely low prices. Unfortunately, you usually get exactly what you pay for, and bargain-basement offers may lead to shoddy work or jobs that take longer than they should. Repairs to these mistakes can end up costing more than the original project.
Moving furniture: The room you refinish will need to be cleared of any furniture or furnishings before starting the project. This is generally not included in the estimate for a project, and if the contractors have to take care of this themselves, they may charge a premium for the service. This can not only prolong the project but can also inflate the cost. You may be able to save money by doing the furniture-moving yourself.
Removing carpet or other flooring: If the hardwood you want to have refinished is beneath old carpet, vinyl flooring, or another material, the refinishing contractor will charge extra to remove it for you. Make sure you get an estimate on those costs. You will likely find that doing this work yourself is a good way to save money.
Repairs: If a floor is damaged beyond a certain point, refinishing it won't be effective. In this case, the floor will need to be repaired before it can be refinished. Most refinishers will gladly do this work but for an additional fee that may be higher than that charged by a handyman or carpenter. The better the structural condition of the floor, the more cost-effective the refinishing job will be.
Cleanup: Refinishing a hardwood floor can be a messy process, and unless the cleanup is specified in the contractor's bid, you may need to factor in the cost of a cleaning service when determining the total expense of the project.
DIY vs. Professional Refinishing
Refinishing hardwood can be undertaken by anyone with some experience handling power tools and performing DIY projects, but it's wise to enter into the work with a full understanding of what's involved. The machinery used to do the sanding can often be rented from your local hardware store, along with the purchase of sanding pads, for about $300 to $400 in total cost. You will also have to purchase stains, finish, and any brushes or sprayers that will be required to apply them.
Remember that it will take a professional about five hours total to refinish 100 square feet of flooring, so factor in the time commitment when deciding whether to do this project yourself. A DIYer, on the other hand, can expect to give up the better part of a weekend to do a good job when refinishing a floor. If you happen to live in a very humid climate, then the process of drying stains and finishes can take significantly longer. This may mean that the project stretches out over more days, making the rooms inaccessible for long periods of time while they dry.
A Warning Before You Begin
Refinishing a hardwood floor is a very messy and chaotic endeavor. It involves sending sawdust flying indiscriminately into the air, and this dust can cause allergies or asthmatic reactions in people who are sensitive to it. Wear breathing protection, such as a particle mask, when sanding and cleaning up the dust.
Sanding is followed by the application of stains and finishes, which can smell terrible and be toxic to the interior air quality of the space for short periods of time. During application of finishes, wear whatever breathing protection is recommended by the manufacturer, and provide as much ventilation as you can.
With extensive projects, people sometimes opt to leave for a few days while the dust settles and the fumes clear.