What makes stairs squeak? The noise usually comes from loose treads (the surface of the steps that you walk on) or risers (upright boards that join the treads together). This is normally due to natural shrinkage of the wooden stair components over time. The adhesive that was originally used to bind the risers and treads together might also have failed.
There are several methods of tightening up the steps to reduce or eliminate the creaking. The best way is to work from underneath the staircase, as the results won’t show and you can usually make a stronger repair. If this is not possible you will have to tackle the problem from the other side.
Repairing squeaky stairs from above
There are three main methods of tightening up loose stair parts:
1. Screw the treads down
The best way of fastening the treads securely to the risers is by screwing them down. Three screws per tread is normally enough. Drill pilot holes through the tread in line with the riser, ideally using No.8 x 38mm countersunk screws, then drive in the screws below the surface of the tread. If there is no stair carpet to hide blemishes, conceal the screws with matching wood filler.
2. Nail down loose treads
A simple repair is to hammer nails into the edge of the tread at a central point where it connects with the riser. For the best grip, insert the nails in pairs so that they are angled towards each other over the creaky spot. Drill pilot holes first to avoid splitting the wood, then drive the nails below the surface and cover with wood filler.
3. Glue on a moulding
Try adding a piece of quadrant moulding (shaped to form a quarter circle) to give the tread extra support. You can secure it to the top or bottom of the riser, or both. For the best results, stick the moulding to both the tread and the riser. This method is more aesthetically pleasing than using screws or nails – however, if your stairs are uncarpeted you will have to add the mouldings to every step, not just the creaky ones, so that they all look the same.
Repairing squeaky stairs from below
If you can get underneath the staircase you may be able to carry out more effective repairs – but remember to wear eye protection as you will spend a lot of time looking upwards. There are various options:
1. Insert blocks or brackets
A good way of strengthening the join between tread and riser is to use small triangular wooden blocks, known as glue blocks. Position a block in each corner of the step under the tread and against the riser, and glue into place. Secure with screws – drive two upwards, into the tread, and two horizontally, into the riser. If possible, get a helper to stand on the tread while you drive in the screws.
Alternatively you can secure small rectangular blocks of wood, known as string blocks, to the corners of the steps to fasten the treads to the strings (supporting boards that run along the side of the stairs). If necessary, you can use these in addition to the glue blocks for extra strength and rigidity.
2. Replace wedges
Make sure that the wooden wedges – which are used to lock the stair treads and risers into their matching slots – haven’t fallen out or begun to slip. Replace any missing or damaged wedges and glue loose ones back into place before tapping them firmly home with a mallet.
Small ‘slip’ wedges, or shims, are another effective way of tightening the joints between risers and treads. The wedges should be around 30mm long and 3mm thick, tapering down to a point. Glue into place, then use a sharp chisel to shave off any protruding ends.