INSTALLING HARDWOOD FLOORING

DYI - Installing unfinished, solid wood floors, especially installing pine flooring

by Lee Edwards, owner of Old Texas Floors

This page is NOT intended to be a comprehensive tutorial on how to install your floors; it’s just some DIY resources for further study and some tips that emphasize points that are easy to miss. This page emphasizes nail-down and staple-down installations onto wood subfloors, but some of the points apply to glue-down installation, which is often done directly onto concrete subfloors, and there's a short section specifically about glue-down applications. FYI, if you want to do a nail-down installation over concrete, you can put down a moisture barrier and then a plywood subfloor, then nail your flooring to the plywood subfloor. All right, here are my personal additions to the installation info that's available to you elsewhere.

Should a homeowner install unfinished flooring?

Advantages

• You’ll make sure to do the job with great care
• You’ll save a lot of money
• You’ll get to design every detail of the floor layout/patterns, choosing every board’s location

Disadvantages

• You’ll pay back some of that saved money in rented and purchased equipment (underlayment, stapler, face nail gun, edge nail gun, nails, miter saw, table saw, rubber mallet, big sander, little sanders, sanding pads, replacement sander parts, finish (hundreds of dollars), finishing applicators, masks, respirators, gloves, plus many miscellaneous items)
• You’ll spend a whole lot of time learning how to do it, then doing it
• You’ll make small mistakes that a pro wouldn’t, and there’s the chance that you’ll make some big mistakes
• Your back will be angry at you

It’s a tough call for someone who’s handy, but hasn’t done this exact job before. It’s a big No if you’re not pretty handy already. A compromise is to have a pro do the actual installation, then you do the sanding and finishing, which I think are not as complicated as the installation, but still challenging to do well. If you do the finishing, choose a finish that’s not terribly complicated. 

    You might look at some of the resources below to help you decide.

National Wood Flooring Association’s Installation Manual. This manual costs $100 to download. It goes into moderate depth about many different installation topics. You'll still probably want more info on some topics, but it certainly offers a lot. You can view the Table Of Contents before deciding whether to buy it.

Don Bollinger’s Book and Videos. These are a bit dated, but this pro installer and white-collar dropout is a great teacher, so the book and DVD are both helpful. You often can get them new or used at Amazon.com. His book is Hardwood Floors: Laying, Sanding and Finishing. His videos are Laying Hardwood Floors and Sanding And Finishing Hardwood Floors. His emphasis is on nail-down installations, not glue-down.

Underlayment. 30# felt/asphalt paper is commonly laid down between wooden subfloors and flooring, but if you want a quieter floor, check out the Quiet Walk underlayment, which does a good job of reducing the clomping sound of feet on hardwood flooring, especially for stairs and upper stories.

Installing the floor—points that are easy to miss
* Moisture Content. It’s important that the moisture content of your wood and of the subfloor be similar. Some people recommend a difference of no more than 4%, and some recommend trying for just 2% with pine. Some flooring is very moist, but Old Texas Floors’ pine is relatively dry, which leads to a shorter drying/acclimating time once you have it at the installation site. You still need to give it 3-10 days to acclimate. The safest way to do this is to get a moisture meter (under a hundred dollars at Amazon.com and verify that the subfloor and flooring boards are within 2-4% of having the same moisture content. If your flooring has been rained on, be sure it’s dried out thoroughly before installing it.

* Subfloor Leveling. If your subfloor is wavy, your floor will be wavy and creaky. Thick underlayment can hide some unevenness, but your best bet with wood subfloors is to smooth out any humps with a powered sander and very coarse sanding pads. For concrete floors, there are specific leveling compounds you can apply.

* Crooked Rooms. Be sure to measure the room before installation to find out how much the room deviates from being perfectly rectangular, then make a plan for compensating for that deviation (Bollinger’s book describes options).

* Best Fit. Consider cutting a whole “course” or row of boards to size before nailing down any of that course. This allows you to make sure that the boards make a nice, straight line together. Sometimes one board sticks out just slightly, and a different board will fit better with the rest of that course.

* The “extra” width. Before starting installation, measure to estimate how many rows of boards each room requires; if a room takes, for example, 7.5 boards to go from wall to wall, plan ahead about whether you want the half board at one end of the room or in the middle. This is especially relevant if the room requires just a fraction of a board’s width to reach from wall to wall (so you’d be putting in a narrow strip) AND the room isn’t very square: narrow strips against a wall really show any crookedness. You may be better off with a  narrow strip in the middle than at one end. A room that requires, e.g., 7.9 courses is easily dealt with by shaving off a bit of the last board with a table saw, but a room that requires 7.2 courses is going to be tricky.

* Expansion Gaps. Be sure you allow space at the edges of each room for the wood to expand with heat and humidity. The dimension in which the most expansion occurs is across the grain, not with the grain (on the sides with the tongues and grooves, not on the ends of the boards.

* Gluing. This is a huge topic; I'll just mention a few points here. (1) It's crucial that your boards be very straight in the horizontal dimension. Glue (called "adhesive" by industry folks) can hold a crooked board straight for a while, then allow it to shift over time--NOT good. This is one reason we're very careful to sell only straight boards. (2) Most glues are made to work with moderate-to-thin boards, 1/2"-5/8" thick, and not with thick boards. If you want to glue, e.g., a 3/4" thick board, make sure your glue is warrantied for that thickness. An alternative, as I mentioned above, is to nail down a layer of plywood, then nail (any thickness of flooring you like) into the wooden subfloor. (3) It's hugely important that the concrete subfloor not be too wet and that it be sealed to prevent slab/subfloor moisture from seeping into the flooring. NWFA recommends only 2 methods for assessing this moisture: calcium chloride testing or a relative humidity probe. Most concrete subfloors may be dry enough, but if you get one that's not, you'll regret not getting professional help on assessing the moisture. One of the big and reputable manufacturers of glue/adhesive is Bostik; they'll consult with you on the phone for free.

* Antique Nails. Antique, large-headed nails look wonderful and historical with this wood, but their large heads can crack this very dry wood; it’s extremely difficult to hammer the heads down below the surface so you can sand over them; and you can’t install those nails with a nail gun. If you really, really want to use these nails, consider drilling big pilot holes and countersinking the nails so that your sanders won’t get worn out trying to sand the nail heads.

* Face Nailing. With narrow wood (3” wide and smaller), the wood is held in place sufficiently by the tongue and groove fit and by nails angled into the tongue, so very few nails are placed in the visible face of the wood (very little “face nailing”). With “plank” flooring (flooring with widths over 4”), it is typically necessary to add face nailing. You can leave these nail holes exposed, or you can fill them with wood filler between installation and sanding. Be sure to recess each face nail by at least 1/8” so the nail’s head won’t be exposed once you sand the wood down a bit.

* Saws. You can cut corners by just using your trusty, old Skilsaw/circular saw, but it’s much easier to get fast and straight cuts using a miter saw for cutting the ends of boards—which you’ll do many, many times during installation—and a table saw for “ripping” boards to smaller widths—which you’ll need to do probably a couple times per room (last board, thresholds, closets). I suggest you either cut each end of every board to make sure it’s square, or at least check quickly with a square to make sure each end is at a perfect 90 degree angle. A 10” miter saw cuts 5” flooring easily, and a 12” miter saw cuts 7” flooring easily. Any table saw with a guide can do the ripping for you.

* Nail Guns. Use them. Yes, you can do it by hand (hammer and finish nails), but it gets old fast doing all the nailing and then countersinking each individual nail with a punch. And there are special nail guns built to do the edge nailing that shoot a nail into the tongue of each board at a 45 degree angle, at just the right depth, and drive the board snug up against the board behind it. It’s good. The nails even have barbs built it in to keep them from wiggling out over time. Face nailing is less specialized, but a finish nail gun will still make your job much easier than doing it by hammer. Nail guns (at least an edge nailer) are probably a good idea if you’re doing over a hundred square feet. Some edge nailers are made for specific wood thicknesses, and some are adjustable. This could be important, but in my experience, there’s some forgiveness/flexibility.

* Wood Filler. After you install the floor, and before you sand it, you have a decision to make about whether to fill any or all of the nail holes and cracks with wood filler. Leaving them unfilled gives a rustic, earthy, cabin-like look. The downside is that dirt and lint will gravitate towards them. Filling the holes and cracks will give you a smooth, elegant, expensive look. Unless you use Bollinger’s technique of spreading  sawdust and varnish over the whole floor, then scraping/sanding it off, filling the holes and cracks one by one takes a lot of time, plus you lose some of the rustic character. The place I would most recommend putting wood filler is on the sides of any thresholds that have boards abutting them at 90 degree angles. It’s extremely hard to get all those board-ends to align perfectly, and wood filler can smooth out the fit. If you want to go the extra mile with wood filling, get multiple colors to match the different colors of different boards—probably a light brown “natural” color, a darker brown, and a reddish brown (not the brighter red). The appropriate color will blend in visually with the particular board much better.

Sanding

* Sanders. Historically sanding has been a great way for a rookie to ruin a floor, but now there are a couple of very user-friendly sanders available. Home Depot rents the Square Buff, a sander with a big, rectangular pad that moves in a randomized pattern also. The Square Buff makes it pretty hard to mess up your floor, and it can get VERY close to edges of rooms, which reduced the amount of time you have to spend going around the edges with a smaller sander. Lowe’s has rented a fantastic sander, but they're getting very hard to find; try the Paint departments (NOT the main switchboards) of your local Lowe's locations. It's the Varathane EzV sander, which has 3 7” pads that move in random orbits. It’s fairly easy to use, though it’s very heavy to move. It does an amazing job of vacuuming up the sawdust it creates. Lean it forward just a bit to get good contact with the floor. With either sander, buy plenty of extra pads of each grit, and return those you don’t use; you don’t want to get caught short on pads. You’ll also need a smaller sander or two (it’s easy to burn out the moving parts, not just the pads) to get into corners and some edges. Small (5” or 6”) random orbit sanders will do the trick. There are special corner sanders with pointed pads, but if you're very concerned with the corners, just fold up a piece of flat sandpaper and do it by hand, saving the hassle of buying a tool just for corners.

* Face Masks. Be sure you use face masks designed for sanding to protect your health! Besides the health issue, you'll hate snorting all that sawdust.

Applying Finish

* Respirators. Most finishes are very toxic during application, so be sure to wear a respirator, not just a simple, white face mask. You can get a spray-painting respirator at your hardware store for $30, and it’s worth it. Many of them keep out the chemicals so effectively that you’ll be unaware of the horrible smell in the house.

* Applicators. Brushing on a finish works great except for the toll on your back. Applicators attached to mop handles are very convenient. Beware of the affordable, synthetic lambswool applicators: they’re easy to use for sweeping finish onto your floor, but if they shed “hairs” at all, the stray hairs can show up blatantly in your hardened finish. Same thing with rags: beware of rags that shed strings.

* Finishes. See our Finishes page for info on the various types of finishes available.

Good luck! Please send me pictures, whether you do the installation or hire a pro.

Lee Edwards, Owner of Old Texas Floors