Kitchen Ceiling Replacement & Plasterboard Re-Skim by a Plasterer in Lewisham

This project took place in a Victorian terraced house in Lewisham, SE13. The property had an older-style kitchen that had been partially modernised with fitted grey shaker-style units, an integrated oven and a stainless steel extractor. Despite the updated fittings, the original lath and plaster ceiling above the kitchen had deteriorated to the point where it could no longer be retained. The kitchen ran the full depth of the rear of the house, making it a sizeable ceiling area requiring a complete replacement rather than a patch or overboard solution.

When our team first assessed the kitchen ceiling, it was clear the existing lath and plaster structure had failed. Image two shows the ceiling fully stripped back, revealing the original timber joists and the underside of the floorboards above. Exposed electrical cables were running between the joists — evidence of a recent rewire — and sections of old lath were still nailed across the underside of the joists in a crumbling, unusable state. The perimeter of the ceiling showed remnants of old plaster keys that had completely separated from the substrate. No section of the existing ceiling could be retained, and the full span from wall to wall required new plasterboard before any skim coat could be applied.

The full scope of work involved stripping the remaining lath and plaster from all ceiling joists across the kitchen, clearing all debris, and then cutting and fixing new plasterboard sheets directly to the exposed joists before finishing with a two-coat skim. Specifically, the work included: removing all remaining sections of original lath and loose plaster key from the joist faces; co-ordinating with the client's electrician to ensure all cables were correctly routed and positioned through the ceiling void prior to boarding; cutting 12.5mm plasterboard sheets to size and screw-fixing them at 150mm centres into the joists across the full ceiling area; taping all board joints with scrim tape before applying a bonding scratch coat to the entire ceiling surface; allowing the bonding coat to partially set before applying a finish coat of multi-finish plaster, worked back with a clean steel trowel to a flat, paint-ready surface; forming a recessed downlighter aperture visible in the finished image, with the back box left clear for the electrician to complete final connections. The walls in the kitchen were in an acceptable condition and were not re-skimmed as part of this contract — the scope was ceiling-only.

Before any plasterboard was lifted into position, the kitchen units, worktops, appliances and floor were fully sheeted in heavy-duty polythene, sealed at the edges with blue masking tape — as clearly visible in image two. A plasterer's hop-up step and an aluminium trestle were set up to provide safe working height across the ceiling. All joist faces were checked for level, and any low points were packed out before boarding began. The electrical cables running between joists were carefully gathered and temporarily secured to avoid being trapped behind the new boards. A PVA bonding solution was applied to the face of the new plasterboard sheets prior to skimming to reduce suction and extend the working time of the multi-finish plaster.

With the new 12.5mm plasterboard fixed securely across the full ceiling span, the plastering process began with scrim tape applied along every board joint to prevent the skim coat from cracking at the seams. A bonding scratch coat was then applied across the entire ceiling surface, working in sections to maintain a wet edge. This scratch coat was ruled off and left to firm up before the finish coat of Thistle multi-finish was applied. The finish coat was spread at an even thickness of approximately 2–3mm using a wide steel plastering trowel, then laid off in long, overlapping strokes to pull the surface flat. As the plaster began to set, the ceiling was trowelled back with a damp brush and steel trowel to close the surface and remove any trowel marks. The recessed downlighter positions — four visible in the finished image — were kept clear throughout. The finished ceiling, captured in image three under warm ambient light, shows a flat, closed surface with no visible joints, ready for mist coat and decoration.

The primary challenge on this job was the volume of exposed electrical cabling running freely between the joists when the old ceiling was stripped out. The cables needed to be managed carefully during the boarding stage to avoid being buried or pinched behind the new plasterboard. Working around live and dead cable runs in a functioning kitchen — with units and appliances already in situ — required careful coordination. Additionally, the kitchen ceiling spanned a long, narrow room, which meant the plasterboard sheets had to be supported overhead for extended periods while being fixed into position, requiring two operatives working together throughout the boarding stage.

Prior to any plasterboard being fixed, our team worked through each joist bay to identify every cable run and ensure each one was either fed through the correct knockout in the new board or left accessible at the point where a downlighter back box or pendant drop was required. Cables that needed to pass through the boards were measured and dropped through pre-drilled holes before the sheets were offered up. The two-man team worked in tandem — one supporting the board at height while the other drove screws at 150mm centres into each joist. This approach allowed the ceiling to be boarded efficiently without any cables being trapped, leaving the electrician able to complete their second-fix connections cleanly once the plaster had dried.

Image three shows the completed kitchen ceiling after skimming and initial drying. The new plasterboard ceiling runs flat from wall to wall with no visible board joints, no cracking and no variation in level. Four recessed downlighter apertures are positioned evenly across the ceiling with clean, circular cut-outs ready for the electrician. The pendant drop point is left with cables hanging clear at the centre of the room. The walls, protected throughout by dust sheets, required no remedial work once the ceiling was complete. The finished ceiling was left to cure fully before the client's decorator applied a diluted mist coat as a primer.

The client was able to hand the kitchen back to their electrician for second-fix downlighter installation within three days of the plastering being completed. The ceiling dried evenly with no cracking at the joints or along the perimeter. Once the mist coat was applied by their decorator, the surface took paint uniformly with no suction variation. The client commented that the finished ceiling looked noticeably better than any of the other rooms in the house, which still had their original lath and plaster in place — and they have since requested a quote to replace the ceiling in the adjacent dining room.

Replacing a kitchen ceiling above fitted units and live appliances is not a straightforward boarding job. The combination of existing electrical cabling, limited working access above the units and the need to maintain a level board plane across a long ceiling span means errors in boarding translate directly into a visibly uneven finished surface. Cutting corners on screw spacing or failing to tape joints before skimming will result in cracking along board seams within months of decoration. Using the correct 12.5mm board weight, fixing at the right centres into structural joists, and applying a proper two-coat plaster system ensures the ceiling performs correctly over the long term.