Asquith Villas, Wandsworth Common

3 May 2017


Basement type: New build Building type: Residential
Type of waterproofing: Type A & B Member: Sika

The Project

CJ O’Shea and Co. Ltd, created a stunning new development at Asquith Spencer Park, comprising of four new homes designed by Chassey and Last Architects for Landview Properties, set within acres of rural scenery close to Wandsworth Common. Each home covers in excess of 425m2, with a lower floor basement, plus four additional floors above ground, together with associated landscaping and parking.

Project Team

Owner: Landview Properties
Architect: Chassey and Last Architects
Main Contractor: CJ O’Shea and Co. Ltd
Concrete Supplier: Hanson Concrete
Waterproofing System: Sika UK Limited.

The completed the basement area will provides an extensive cinema and games room, together with a utility room and guest bedroom. The concept is to give the homeowners a seamless blend of high-end technology with refined family living.

A cost effective watertight solution for the basement was required, that would ensure complete watertightness and adhere to the principles laid out for Grade 3 of BS 8102:2009.


During the design development, CJ O’Shea chose a dual system from Sika Limited. This consisted of SikaProof® A, a totally new concept in membrane barrier systems, together with the Sika® Watertight Concrete system.

The membrane surface of SikaProof® A is embossed with a grid pattern, which contains a sealant, and is topped by a thin layer of fleece which forms a mechanical bond to the concrete when it dries. It offers additional protection, due to the integrated sealant, which bonds tightly with the surface of the concrete, forming mini watertight compartments. Therefore, even if the membrane is damaged or pierced, moisture or pressured water cannot spread between the membrane and the concrete structure as it is contained within the small damaged grid square.

In this ‘belt and braces’ construction, the Sika® Watertight Concrete system is also being used for all basement construction. Watertightness of the concrete is obtained by incorporating Sika admixtures in the mix. Hanson Concrete supplied 400m3 of Sika Watertight Concrete to the project. Joints were sealed using the BBA approved SikaSwell® jointing system, which consists of joint sealing profiles that expand on contact with water.

See Sika's company profile here.