We’d like to start this post by thanking the homeowners for giving us the opportunity to work on this window. We regularly get to work on historic and unique pieces of joinery but not very often is it as challenging and requiring of an owner’s trust as this example.

Curves present a challenge to the joiner in that in order to join the curves, you need to be able to cut repeatably and accurately using machinery designed to cut straight lines. To carry out a repair, you also need to consider the inevitable settlement and wear and tear of the 100+ year old windows.

We started this repair with an investigation of the design, assembly and condition. Almost every cut needs some sort of jig, fixture or modification making so setting out the exact scope of the work helps keep control of the budget.

We identified some areas of the sill that didn’t need replacing as their condition was excellent. We also settled on a plan for repairing the sashes and sections of sill that did need attention.

The glass was original to these 1920s windows and was manufactured using the drawing process which gives the tell-tale vertical ripples in the reflection. As the rest of the glass was original too, using float glass for the replacements would have been quite obvious so we sourced some drawn glass, which is still manufactured in France and Germany.

The putty, being 100 years old or so, had dried to a hard layer, firmly attached to the rebate of the sash. We have a number of different methods to quickly remove old putty without damaging the timber of the sash. This ensures the new glass gets a good bed of new putty and enough depth on the face.

The timber available during the 20s was typically slow grown and therefore is much more rot resistant and stable than the equivalents we see today. It’s therefore a good idea where possible to retain as much of that original timber as we can. Here, we were able to localise the repair only to the corner of the sill and bottom area of the weight box planks using Accoya with a minimum rot resistance of 50 years.

To complete the repair and ensure a long life for the window, we made a small repair to the bottom sash which also needed a little TLC.

With some master bricklayers on the case with the wall, we were given the task of repairing the porch. Made from a mix of oak and elm rounds, the original would have been made using the scribe rule method to align the joinery.

We wanted to keep as much of the original timber as possible so we set about repairing the joints which had snapped in the accident.

Templates were employed to give the correct orientation and alignment for the tenons. After that, it was just a case of blending the existing into the original a little more before reassembling on site.

With the surrounding lead work on the roof, it was a tight spot to get into but with sharp chisels and a practiced hand we were able to clear away the rotten timber to good wood and form a joint.

Using Accoya for the replacement means the owners won’t experience the same issues in years to come.

We started with the repairs to the long drip beneath the arch. The drip was formed by an extra deep head on the casement windows so it was necessary to machine this back to good wood using a template, then form a groove for a tongue on the new Accoya drip to join into.

We cleaned up the damaged area and jointed in a new rebate for each sash, copying the original design exactly.

With the repaired meeting rails in place, we could refit the sashes and make any minor adjustments necessary to ensure the window wasn’t the cause of any more frustration in the house.

The awkward part of these repairs is getting access behind the brickwork so some creative use of hand tools and the odd jig and fixture help get perfectly square and true surfaces to enable a repair that will last.

For the replacement planks, we used Accoya wood for its rot resistance. With the planks cut and jointed in, we then re-established the pocket so the window can continue to be serviced in the future. Finally, we applied some coats of a good quality primer to help the decorator, and re-pointed between the stiles and brickwork to close the job up.

With no signs of rot, it was apparent that the joints had failed, causing the sash to sag and become stuck. After carefully opening and removing the sash, we also noticed that the friction stay was damaged and would need replacing.

We took the bottom rail out, cleaned everything up and then it was just a simple case of re-gluing the joint back together. With a new friction stay fitted, we could put the window back together and leave it working perfectly.