Renovations in Mayfair

Very little in Mayfair can be changed on the outside, which is precisely why the renovations here are so involved on the inside. The houses around Berkeley Square and Grosvenor Square are grand period buildings, a high proportion of them listed, and listing covers the staircase, the joinery and the plasterwork as readily as the front elevation. Behind the Bond Street frontages and around Shepherd Market the grain gets tighter, with residential upper floors sitting over shops and offices. A renovation in W1 is a question of consent first and construction second, and that order almost never reverses.

Consent comes before construction

Listed building consent is a separate application from planning permission, and Westminster City Council determines it. What triggers it is alteration to fabric contributing to the special interest of the building, which in a Mayfair townhouse can mean a cornice, a shutter box, a run of original boards or the stair balustrade. We are the contractor. We build to consent that has been granted and to the drawings your architect and conservation adviser produce, and we will say plainly when something shown on a drawing appears to need a consent nobody has yet obtained.

Where the fabric is protected, the gains come from the parts of the plan nobody sees from the street. Lower ground floors that began as service rooms become kitchens and family space. Rear closet wings get rationalised. Daylight is drawn down through the section instead of being added to the front. These are the moves that make an eighteenth century plan work for a modern household, and they are also the moves most likely to be approved, because they leave the elevation and the principal rooms as they were found.

Old fabric, old mortar

Solid brick laid in lime mortar behaves differently from modern cavity construction, and treating it otherwise is how period houses get damaged. Lime lets a wall move slightly and dry outwards. Repointing in a hard cement mix traps moisture and pushes the damage into the face of the brick instead. The same logic governs plaster: lime plaster on lath wants a breathable finish, not a sealed one. On listed work we repair with matched materials rather than replacing wholesale, which is generally what the consent requires in any case. Matching a historic mix is skilled work and it takes longer, which we say at the outset.

Floor structures in these houses are generous but not modern. Deep joists span further than you would expect, yet a century of notching for pipes and cables has often taken a good deal of their strength away. Any new opening, and any change of use that adds load, goes to a structural engineer we appoint before a saw is picked up. We install to the design issued, keep the structure propped while load transfers across, and leave bearings open for building control to inspect before anything is closed up. It is slower than guessing, and it is the only way to be certain of the result.

Access off a Mayfair street

Kerbside space is the scarce commodity here. Bays are controlled, loading windows are short, and a skip needs a permit from Westminster City Council before it lands, assuming a skip is workable at all. On several streets it simply is not, so waste goes out bagged on staged collections and materials arrive on the day they are needed rather than in bulk. That has to be priced and programmed honestly at the outset, because pretending otherwise is what turns a fixed completion date into a moving one. Neighbours and the managing agents either side are told what to expect and when.

Mews properties behind the main terraces are a separate proposition again. Narrow, often only two storeys, with a former coach house at ground level and no rear access whatsoever, they take every material through the front door. Renovating one is rewarding work, but the sequencing has to be exact: once a staircase or a ground floor slab is out, there is no second route in. We plan those jobs backwards from the largest single item that has to fit through the opening. Once that sequence is agreed it is followed exactly, because there is no room to improvise.

Where most Mayfair projects start: whole-house refurbishment in Mayfair, everything we cover across Westminster, renovations in Marylebone, renovations in Pimlico and renovation order of works.