There’s nothing more annoying than a floor that creaks and squeaks every time you step on it. There are a number of issues which can cause your floor to creak and most can be remedied, however to do this job properly will take some time and might involve the removal and reinstatement, even renewal, of some of the floor. So be prepared for a bit of upheaval and set aside plenty of time.
What causes floorboards to creak?
In order to establish what is causing your floorboards to creak, you’ll need to pinpoint the exact location of the creaking by having someone step on the floor whilst you listen closely for the noise and look closely for floorboard movement. Once you’ve located the exact location, you can assess the area and determine which of the issues below is responsible for your loose boards.
Although any floor can squeak, hardwood floors and staircases are the most common culprits. Squeaks happen when a house settles and wood flooring dries and then expands. This causes the floorboards to rub against each other, against the joists, or against the nail casings. It can be helpful if you have access to the space beneath the floor, such as a basement or crawl space, otherwise you will need to lift the boards. If you are at all unsure as to what’s causing the creaking, then this is not a DIY job as you could risk making the problem even worse. If in doubt, seek the advice of an experienced carpenter.
How to fix squeaky floorboards
Once you’ve worked out what’s causing your floorboards to creak, you can decide on the best steps to take to remedy the problem. Here are some of the most common issues and how to resolve them:
Incorrect nails
If the wrong nails have been used to fit your flooring to the floor joist your boards will creak. This could mean that the nails are not long or strong enough to keep the floor secure, which allows it to move around when pressure is applied. To solve this problem, you’ll need to remove the existing nails/screws and use the correct ones to refit your floorboard, which should be quite a straightforward task.
In the case of chipboard floors these nails should be annular ring shank nails. These nails (usually 2 inches long) have serrations all round the shaft and are slightly screw-like in appearance. To fix a loose floorboard you need to fix the board to the joists using screws which penetrate the joist by at least the same depth as the floor itself. These should be fixed at 400mm centres in both directions, making sure you countersink the screw heads for a flush finish. Before you start screwing the boards, make sure you check for pipes or cables beneath using a pipe detector.
Inadequate fitting of nails
If the nails are fine but the flooring has not been correctly nailed to the joist, this will result in movement too. Similar to the above, you will need to remove the nails/screws and assess where it’s gone wrong – the nails might be too far apart, or they may have missed the joist or slipped out. In order to solve the problem, you should fix the board to the joist using screws to secure it, rather than introducing more nails.
Gaps between the floor and joist
You might find that the joists that are supposed to support the board are not doing so because there is a gap between the top of the floor joist and the underside of the subfloor. If you have access to the space underneath the floor then this is a lot easier to fix, as you will not need to lift your floorboards at all. Once you can get access to the top of the floor joist, apply some carpenter’s glue and fix a thin wood shim to fill that gap between the joist and the underside of the subfloor.
Make sure that the wood shim is the correct height, otherwise it could raise the subfloor and cause an ugly bump in your flooring. If the gap has been caused by the floor joist warping or shrinking over time, then you will need to install a long plank of timber alongside the affected joist, at a slightly raised height, so that it reaches the subfloor and fills that gap, acting almost like a replacement for the damaged joist.
Unsupported end joints
Another cause of a creaky floor may be an unsupported end joint between floorboards. The floor joists need to be absolutely solid and of the correct size to prevent movement across the span they are bridging. It is also vital that the joists are fixed very solidly at either end, are spaced at the correct centres (usually 400mm) and cannot move in their wall sockets or joist hangers. The tail of the hanger should be firmly built into the wall and the joist firmly fixed into the hanger.
If the joists are built into the wall this should be done in a way which prevents both rotting and movement. To fix the problem, the floorboard falling short of a support must be lifted and an extension added to the joist to support the board end. As this will require cutting the tongue of the board to be removed it is not an easy DIY job, so it’s best left to an experienced carpenter.
Twisted or sagging joists
Squeaky floors may also be caused by twisted or sagging floor joists. These might have twisted due to shrinkage or poor workmanship during construction. They may also be too small for the floor span and result in the floor joist sagging. This can lead to movement between the board and joist resulting in creaking. You may need to add additional bridging pieces or ‘noggins’ at regular intervals across the floor to strengthen it. This is sometimes done in a herringbone fashion using battens, but more often these days is done using solid timber the same size as the joists themselves. However, this is a big job involving lifting up the floorboards. It is a good idea, especially when doing a loft conversion (and required on all other floor levels), to strap the first three joists on either side with a restraining bar (know as a joist strap) which is fixed to the wall using plugs and screws or resin fixings.
Weakened joists
It is also worth checking the joists to see if an overzealous electrician or plumber has drilled excessive holes in the joist to facilitate a plumbing pipe or cable, resulting in a weakening of the joist. This also applies to notches which are taken out of the top of the joists and pipes/cables are set into these notches. These can weaken the joist allowing it to move. Joists can also be damaged due to external issues such as damp or rot. If the joists are rotten or weakened then you will need to replace them.
Uneven subfloor/bad underlay installation
Similarly to suspended wood floors and joists, if your subfloor is uneven it could leave gaps between your floated or glued down wood floor causing it to creak. This is also true when the underlay has been fitted badly, leaving gaps and spaces between the floor and subfloor. You may potentially be able to solve the problem by finding a small hole in the plank directly over the gap and injecting epoxy into it. However, if the space is quite large, this won’t solve the problem. Instead, you’ll need to lift up the floorboards, level the subfloor and lay new floorboards down.
Flooring has not acclimatised
It’s important to allow your floorboards time to adapt to the temperature and moisture content of their new environment before having them fitted. If this isn’t done correctly, the floorboards are likely to expand or contract after they’ve been installed which can create gaps between the boards that rub together and squeak when walked across. Unfortunately, this is a case of damaged flooring that will need replacing rather than fixing - only this time make sure to allow your new flooring to thoroughly acclimate before having it installed.
Excessive moisture
When wood flooring is exposed to moisture it will either expand or contract. If an area of the room has suffered from a water leak or flood, the wood will absorb the water and change in shape and size which can cause warping, gaps and noisy floorboards. Unfortunately, there is no quick fix for this issue and you’ll have to remove the damaged floorboards and fit new ones.
Check for friction
If you find that the creak in your floor is not being caused by any loose boards or uneven subfloor and everything has been fixed firmly and correctly, then there might just be some friction between the boards which is creating the noise. To remedy the problem, try dusting the cracks between the boards with talcum powder or graphite powder lubricant. This will help reduce any friction that’s occurring between the planks of wood and should eliminate the noise.
Stud wall issues
Sometimes the floor is absolutely solid and what is making the squeaking noises is the nails or screws used to hold the ‘sole-plate’ of the new stud walls to the floor. If the floor moves even a tiny bit (which of course it shouldn’t, but sometimes does) the friction between the wall and the floor it stands on can sometimes cause a squeak. The solution to this problem is to drive timber wedges between the wall and floor to take up any possible slack, however if this wedge needs to be more than 12mm at its widest end then the floor has not been put down properly.