Silencing squeaky floors

Floors and stairs only squeak when you're doing something sneaky, like coming back to bed after an ice cream binge at 4:00 a.m. But you don't have to get caught. Let me share my espionage tactics.

If you've got plank floors, memorize which boards squeak and step deftly over them. I use the word 'deftly' with authority, since my stairs have four squeaky steps in succession, meaning I have to haul myself over this thigh-killing span using only the feeble banister for support.

If you have carpet laid over floorboards, you can't just count planks and avoid the noisy ones. No, you need landmarks that help you pilot safely around squeaks hidden under monochromatic broadloom. I personally navigate using a cluster of cat-barf stains that looks just like Orion's Belt, as well as an explosive-looking discolouration where I once dropped a whole pot of cheese fondue.

But you may not be this lucky. You may have spotless carpeting, making it impossible to steer accurately around squeaky spots. I feel for you. You'll have to do an actual repair.

First, a little background, so you know what you're up against; Floor squeaks are invariably caused by space between wood surfaces, as in:

1. Loose floorboards rubbing against flooring nails
2. Loose subfloor (usually plywood or chipboard) rubbing against a nail
3. Loose underlayment (often particle board laid on top of subfloor) rubbing against a nail

In all cases, screwing loose wood elements together usually eliminates movement between layers, and ends the squeak. Sounds simple enough. How many screws does it take to abolish all the squeaks in a small room? I've used as many as 800. Born lucky.

It's always easiest to approach a squeak from the floor below, adding blocking between joists to reduce movement, or using one of the squeak-eliminating products on the market; Squeak Ender, for example, is a clamp that snugs your subfloor against exposed joists.

But sometimes you can't get at your joists, so your strategy needs to be more subversive.

Whether you've got bare hardwood floors or carpeted surfaces, start by flagging all the squeaky places with pieces of masking tape.

In the vicinity of each squeak, the flooring needs to be pulled tight against the joist. To find the nearest joist you can use an electronic studfinder, or probe through the layers of carpet and subfloor with a finish nail mounted in a drill. (The spinning finish nail won't get all furled with carpet fibres like a twist drillbit will.)

Another way to find a joist is to pull the grate off a warm air register and push on the edges of the metal ducting. One side of the register is usually rigid because it's attached to a joist.

Once you have located one joist, you can usually find all the others because they're spaced a standard 16 inches apart, (measured from center to center). Weird things happen to good houses though, so if the 16-inch spacing isn't turning up more joists, you might also check intervals of 19 1/4 inches or even 24 inches. Lay a tape measure on the floor starting at the one confirmed joist, and continue probing along the tape until you have a good idea of how the joists are spaced.

Next, drive a trimhead screw into the floor over the joist. This will pull the flooring tight against the joist. Trimhead screws have relatively small heads that sink through carpet and disappear. Keep the drill speed low so the screw doesn't cocoon itself in carpet fibres and refuse to sink.

If you're working on bare wood floors, pre-drill a pilot hole over a joist and top it off with a 1/8-inch deep countersunk depression that will hold the head of the screw. To make the shallow countersink hole use either the tip of a 3/8" drill bit, or buy a countersink bit. Then sink the screw and cover it with colour-matched woodfiller putty.

TIP: The correct length of screw depends on the distance from the top of your flooring to the joist. If there are repeated layers of plywood subfloor, you'll need a longer screw. At least one inch of the screw should sink into the joist so there's plenty of gripping depth.

If the first screw doesn't eliminate the squeak, drive another screw a couple of inches further along the joist. You're working blind and guessing wildly, so this is where you have to use the force, Luke.

(Someday I'll invent a tool called the Forceluke and do commercials where I say, "Troubled by pesky home maintenance problems? Use the Forceluke." And people would think I paid big money to George Lucas.)

No matter how many screws you drive you may still have squeaks. At that point it may be worth it to you to give up entirely, or pull back the carpet and the underpad, and invite friends over for a night of screwing madness. Re-stretching your carpet is a pain, so you might want to pay a carpet installer to do that for you. But it'll be worth it just to be able to sneak around in your own home.