Bathroom Renovation in London Period Properties: Specification and Design

Bathroom renovation is one of the most value-critical scopes within a full house renovation. Done well, a bathroom in a London period property can be genuinely luxurious and entirely in keeping with the building's age. Done badly, it looks incongruous, leaks into the floor below, and needs replacing within ten years.

Here is how we approach bathroom specification and design in older London properties.

The structural challenge: floors

Victorian and Edwardian properties have suspended timber floors. This is not a problem in itself, but it requires a different approach than a concrete-floored flat.

Deflection. Timber floors flex. Heavy stone tiles — particularly large-format porcelain or natural stone — may crack if laid on a floor that moves. The solution is to increase the structural rigidity of the substrate: typically by adding a layer of 18mm marine ply, fixed to prevent any movement before tiling.

Drainage falls. On a concrete floor, creating the falls required for a wet room or walk-in shower is straightforward. On a suspended timber floor, this typically requires either a proprietary shower tray with integral falls, or careful structural modification to create a recessed area with the required fall. Both are achievable; both require planning at design stage, not as an afterthought.

Penetrations for pipework. All waste and supply pipes pass through the floor structure. In period properties this must be done carefully, particularly near joist bearings and support points. Notching and drilling joists to BS 8103 limits is mandatory.

Waterproofing

Bathroom waterproofing (tanking) is non-negotiable and frequently done badly. The consequence of a failed tiled wet area in a period property is typically significant damage to the floor structure and the ceiling below — expensive to repair and often discovered only when visible damage has already occurred.

We use liquid-applied tanking membrane beneath all tiled wet areas, applied to the manufacturer's specified thickness with attention to upstands, corners, and pipe penetrations. The substrate must be fully dried before tiling. These are basics, but they are worth stating because they are commonly skipped in the name of speed or cost.

Design principles for period properties

Scale. Generous proportions suit older buildings. Oversized baths, freestanding where room allows, large walk-in showers with frameless glazing, and well-scaled sanitaryware typically read better than small, space-efficient formats.

Tone and material. In period properties, classic material palettes — Carrara marble, aged brass or unlacquered brass hardware, ceramic metro tile, stone flooring — tend to age better and feel more appropriate than high-gloss, highly contemporary finishes. That said, ASAAN has also delivered thoroughly contemporary bathrooms in period houses successfully; the key is coherence of the approach across the full room.

Heated towel rails and underfloor heating. Both are expected at this level of specification. Underfloor heating in bathrooms is almost always electric given the typical floor construction — a qualified electrician must install and certify it.

Ventilation. Bathrooms in internal positions require mechanical extract ventilation meeting Building Regulations Part F requirements. This is not optional and should be specified properly, not retrofitted with an undersized fan.

What a well-specified bathroom costs in London

Indicative costs for bathroom renovation in London period properties:

These are all-in costs including design, structural works, waterproofing, tiling, sanitaryware, hardware, plumbing, heating, and electrics.

Our approach

ASAAN has delivered bathrooms across the full specification range in London period properties. We design and specify bathrooms in-house and work with a trusted group of specialist tilers and plumbers.

If you are planning a bathroom renovation, contact us for a consultation. Related reading: Period Property Renovation: What to Know Before You Start and Plumbing and Heating Systems in London Period Properties.