Timber stairs pre-dating the 16th century generally either comprised some form of ladder or were constructed, often in spiral form, from oak baulks. From the 16th century, framed staircases slowly emerged with boards forming treads and risers that were housed in strings. These stairs were initially of hardwood, typically oak, and later predominantly softwood. They frequently provided an opportunity for architectural expression, displaying ornate balustrading and newel posts.

Creaking normally occurs when loose or flexing timbers rub together. Overcome movement between treads and risers by working in diluted PVA (50:50 with water). Additionally, if the stairs underside is accessible, remove loose wedges from the tread and riser ends. Clean and possibly trim the wedges or cut replacements, apply diluted PVA and drive them firmly home. Finally, readhere loose triangular ‘glue blocks’ or, where necessary, provide new ones in the angles between the treads and risers. If the stairs underside is inaccessible, wedge joints from above.

A long, diagonal split in a baluster can be repaired by working in some PVA and carefully attaching a clamp while this sets. A broken baluster may require dowelling and gluing back together in a workshop. Where loose, a baluster might be resecured with glue and a countersunk woodscrew fixed diagonally through the end into the handrail or string. Where a baluster is missing, a suitable replacement will frequently have to be purpose-made, particularly where decorative.

Occasionally, more serious defects result in treads and risers separating from a string. Reasons include settlement in a flanking wall, a defective joint at a string end or differential shrinkage of staircase timbers. Repair can involve carefully jacking up sagging stairs and forcing a string back into position. Wedges might be driven between a flanking wall and inner string to move it back, or perhaps a horizontal prop or tie rods used to pull in an outer string. Underlying structural problems must be addressed first.