HOW TO REFINISH WOOD STAIRS
Time to freshen up your stairs and learn how to refinish wood stairs.
Stairs see a lot of wear and tear. From your feet to your dog’s paws, stair finishes are one of the first to go. Refinishing wood stairs follows a similar process as refinishing floors, but it does require more good old fashion hand sanding. Learning how to refinish wood stairs is a 2-3 phase project. Review the steps below.
Strip and sand wood to remove existing stains and finishes. The sanding process will re-level boards by removing the damaged upper levels. You will follow a grit sequence when sanding. A grit sequence consists of multiple sanding passes using various grit sand papers. Bauen will go into more detail in the Perform section.
Stain your wood. This phase is optional, but this the time to apply color to your floors. You will apply 1 – 2 coats of stain to the floor. The wood absorbs the stain and requires a protective finish to lock in the stain.
Protective finish. A protective finish is necessary to ensure longevity. There are many finishes out there, but the most common are polyurethane, wax and tung oil. Factors to consider are VOC content, time, skill level and foot traffic to name a few.
Plentiful products for refinishing wood stairs.
There are tons of product lines out there and it can be very confusing for the DIY’er to know the difference. Stains and protective finishes are like artist tools to flooring professionals, so each opinion you get will be very personalized. You have the products sold in big box stores, specialty stores and those sold directly to professionals. So how do you know the difference? Bauen has a series of articles breaking each one down helping you make an informed decision.
DIY or hire?
Good question. If you don’t have full confidence in your sanding abilities or don’t think you have the patience or time, then it might be best to hire someone. However, it is a great money saving job and you can always work in sections to give your muscles a break!
Your attention to sanding details will make the difference. It might seem like you are sanding for eternity, but better your sanding job the better the results.
Assess your situation before starting. You want to make sure you are good to go!
1. Was your house built before 1970?
If yes, there is a good chance you have lead paint either exposed or in sub-paint layers. Lead paint is most harmful when dispersed through the air in tiny particles such as sanding dust. We recommend you perform a lead test if you plan on scrapping or sanding during your prep phase.
2. What is the weather like outside?
Think about the temperature in the room and humidity levels. Stains and protective finishes take longer to dry in hot humid weather. Extreme cold temperatures cause the stains and finishes to dry too fast. Spring and fall are the best times of year for refinishing. You also want to be able to open the windows for ventilation!
3. Do any of the products you plan on using have a high VOC content?
If yes, you absolutely need to wear a respirator designed for Volatile Organic Compounds (VOC).This might be a hard question to answer at first since this information isn’t always easy to find. Two easy ways to find the info: Look at the back of the product and towards the end of all the text it will say something like. “Maximum VOC:… or Complies with EPA… Complies with EPA is a good thing since some states regulate products that contain high VOC’s. You can also look up the product’s material safety data sheets (MSDS) online.
4. Do you have other work planned for the area? Such as painting risers and molding or installing wallpaper?
Before you go sanding crazy, it is good to think of other projects you might be considering. In Bauen’s opinion, we recommend performing the sanding process before painting anything near the stairs or doing any other project in which sanding dust might interfere. For example, applying a textured wallpaper should occur after the fact. Image all the dust getting stuck! Make sure to allow at least a week to pass before applying any tape (if that’s your thing) to the finished stairs.
5. Do you have a bathroom on both floors?
You might be laughing but this is a serious question! You should assume that each pass of stain and protective finish needs typically at least 6 hours to dry. You don’t want to get stuck! To make things easier, do every other stair. It will take longer to finish but at least you will be comfortable.
Perform this work during ideal temperature times. Too hot or too cold can have a big effect on stain and protective finish absorption.
1. Protect your space. Sanding dust can magically travel everywhere. It is highly recommended you seal off your stair area using thick drop cloths. Bauen recommends 2mm thick.
2. Protect yourself. Wear a NIOSH approved N-95 or N-100 sanding respirator when sanding. Even though you don’t see the particles, they are out there. We also recommend wearing ear plugs and goggles when operating power sanders. These machines can kick up more dust than normal hand sanding. Lastly, work gloves are optional. Coarser grits such as 36 and 50 can turn your hands into sandpaper.
3. Remove. If you can, remove any molding that might be on the treads, particularly where the tread meets the riser. Remember, this is always a good time to replace molding!
3. Clean the area. Remove any existing carpeting at this time and give the area a wipe down with a moist microfiber cloth to remove dust a debris.
1. Protect your space. VENTILATE. Open windows in areas surrounding the stairs. If it is especially windy outside, crack the windows only a few inches. You don’t want dust debris getting stuck in your stain and finish. If you must remain in the house, designate rooms that will have the doors closed and cracks sealed with tape or towels.
2. Prep your tools and product. If you plan on using a paint tray to hold stain or protective finish, Bauen recommends padding the bottom of the tray. Exposed floor is delicate and you don’t want to run the risk of the metal bottom scrapping the wood. We used paper towels and tape to create a padded bottom. Same goes for metal cans. If you are using a lambs wool applicator for the protective finish, remove any excess dust or loose fur. We run our hands through it and then use a lint roller. This helps prevent fur fragments from getting stuck in your finish.
3. Protect yourself. Wear a NIOSH approved respirator designated for VOC vapors. This is different than a respirator with a N, P or R rating. The respirator will reduce direct exposure to the gases emitted by the stain and protective finish by using a carbon filtration system to absorb the vapors. Wear solvent resistant protective gloves. Double up on gloves if they are thin. Wear clean socks or protective booties over your shoes.
You can’t have too many drop cloths when it comes to keeping out sanding dust. Cover it all! Absolutely wear respirators for all steps!! Your lungs and nose will thank you.
Before we get started, a quick breakdown on your grit sanding sequence
A grit sequence consists of sanding passes made using various abrasive levels, starting with the roughest and moving to the smoothest. The rougher abrasives will remove existing finish and level boards. The smoother abrasives will return the wood pores to a state that will accept a nice level of stain and polyurethane finish. Open coat, aka. the roughest sandpapers should be used as needed, since they can remove a considerable amount of wood very quickly. The idea is to start with the least coarsest paper possible. In many cases that will be 36 – 40 in older homes. However, each floor is different and it can be trial and error in the beginning. There is a science behind all of this but what you need to know is, DON’T SKIP GRIT LEVELS. If you start with a coarse grit, then follow up with medium and then fine. If you get antsy and skip levels, you will be left with a floor that wears easily and stains unevenly. We don’t want that!
Grits within a level are different. Stay consistent.
You will want to stay consistent with your grit sequence if you plan on doing other areas of your home. The final grit level is the most important. A floor finished on 80 vs 100 will absorb stain differently, i.e. they won’t match. The floor finished on 80 will look slightly darker than the 100 since the finer grit will close the wood grain more.
But the wood still feels rough.
That’s ok. You want to expose the wood grain so it can absorb the stain and protective finish. If you sand it too much using finer sanding grits, you will close the grain. In this case, no matter how much stain and finish you put on the floor it will just sit on top of wood.
1. Scrape. Use a carbide scraper to remove areas of old finish build up. A carbide scraper is highly recommended when removing wax finishes. Wax finishes are notoriously difficult to remove with everyday power sanders because they quickly gum up the sand paper. The carbide scraper will expedite the process! Use controlled medium pressure and move in deliberate straight passes along the wood grain. A painter’s tool will also assist you in reaching areas.
2. Sanding Pass 1. Start sanding using your coarsest grit, whether that be 36, 40 or 50. We are using a 36 grit since we have an existing wax finish that needs to be removed. We are using a belt sander to help us with the sanding process, but you can do this by hand – it just takes longer. Whatever method you choose, always move in the direction of the wood grain. You will notice that with whatever power sander you use, there are still unreachable areas. These are typically along the edges and in corners. To tackle these, use pieces of the same grit sandpaper and sand by hand. It’s trial and error with what works for you. FYI: Sanding pass 1 is the most time consuming because you want to make sure all existing finish/stain is removed. This might take you a few passes with the belt sander and by hand. Below are images of different techniques we have found helpful.
We used a 3″ x 21″ belt sander. This size is pretty typical and great for home improvement projects. Use medium consistent pressure in the direction of the wood grain. If you hear a “catching” noise, look at your belts to insure they are still fresh and that you don’t have too much wood dust around. Power sanders are most effective on clean wood.
Use a rubber block sander with strips of sand papers. The block has metal “teeth” that keep the sand paper in place. It also has a little weight to it, which will give you extra sanding pressure. A sanding block is great for areas the power sanders can’t reach. We also like to use it to do a final pass over the entire area before switching grits
Cut up small pieces of sandpaper and use the pressure of your fingers to sand extra close to the edges. This can be more effective that using that sanding block when it comes to edges.This is a good time to wear work gloves to protect your precious hands. Alternatively, we have used bandaids on the sanding fingers. Works great!
3. Clean. Sweep and vacuum the sanding dust throughout the process and definitely between grit changes. Your sanding will be more effective on a clean surface.
4. Pencil marks. Drawing light pencil marks on your floor between passes is a great way to know what areas you have sanded.
5. Keep on going! Keep up the good work and move onto your medium grit. Soon enough you will be on your lightest grit.
Patching & Repairs
7. Phase 1 completed! Congrats. Give the floor a good vacuum and gently remove your protection as to not rustle up too much of the sanding dust. Perform a final vacuum once the dust settles.
Wood is a rather porous material. As you strip and sand your floors you decrease the size of the pores when you move to a higher grit number, i.e. 100 grit. If you accidentally get water on the exposed wood, you open the pores back up. This means the stain and protective finish will be absorbed at different rates – leaving you with areas that look darker than others. To avoid this, be conscious of any sweat or water in the area!
1.Mix the stain. Use a paint stick and gently mix the stain so as to distribute any sediment that might have settled over time. Do not shake the can.
3. Let it dry an then reapply. Allow the first coat to dry. Approx. 4-6 hours. A second coat can be applied if a darker color is desired. Follow same steps above. Remember to remove excess stain!
1. Clean. Lightly wipe down the stained stairs using a dry microfiber cloth. There is a good chance small debris found its way back onto the stairs.
2. Apply Finish. Your application process will depend on the type of finish being applied. For this project we are using an oil-based 350 VOC polyurethane finish. Apply the polyurethane finish using a natural brush and/or lambs wool applicator. We like to use a brush to get close to the edges and the lambs wool applicator to spread the finish. Move in the direction of the wood grain. Work with the finish to ensure an even application. It’s ok to multiple passes with your application tools.
3. Dry. Follow the product directions regarding drying time. Each product varies. For this product, we allowed the product to dry overnight. Water-based and oil-modified products have a shorter drying period.
4. Pick. In between the first and second pass, you should inspect each step and remove any large debris that might have gotten stuck in the finish, such as hair, pet fur, lambswool fuzz or large dust particles. Use fine tweezers so as to not disturb the stain or finish. Be careful not to pick away the finish. If you have any hesitation, just leave the debris. You are more likely to see the missing finish compared to a piece of hair.
4. Sand (If needed). Some protective finishes, particularly water-based and oil-modified, call for sanding in between applications. Sanding is required with these finishes because the water content reopens the wood pores, making it feel grainy. Even though we used an oil-based finish, it called for a light sanding using 220 grit sand paper if we allowed it to dry over a specific amount of time, which we did. Use light pressure! Anything too hard will strip the finish and the stain.
5. Reapply. Wipe down the stairs using a microfiber cloth. You want to remove all sanding dust from the previous step. Let it dry for the time specified.
6. Congrats! You are done. We are sure your muscles are sore and tired! Time to enjoy those stairs – and install that amazing stair runner!