Delta Membranes

Waterproofing Design – a robust solution from Delta

  • 4 Dec 2020

The British Standard regarding structural waterproofing is BS8102:2009 – this standard encourages the use of a Waterproofing Design Specialist to a design team, explain Delta Membranes.

NHBC Chapter 5.4 mirrors these guidelines. In cases of litigation or disputes both BS8102:2009 and NHBC Chapter 5.4 will be used as a benchmark.  

Both standards place great emphasis on creating a robustly waterproofed environment in both domestic and commercial structures.  The advantages are clear in terms of protecting the integrity of a structure.

Delta Membranes

There are three categories of waterproofing systems available:

Type A (Barrier) Protection

Type A waterproofing relies on applying a waterproofing material to the internal or external walls and floor slab of a below ground structure.  The structure itself is not considered to be integrally waterproof.   The Type A protection needs to be 100% defect-free to offer perfect protection.

Type B (Structurally Integral) Protection

Type B waterproofing requires the structure to be built/constructed as ‘integrally water-resistant’.  That the protection from water ingress is the structure itself.  Like Type A waterproofing systems, the watertightness of Type B construction is heavily reliant on perfect installation to be entirely effective.   

Type C (Drained) Protection

Type C waterproofing is known in the industry as a fool proof system. Unlike Types A and B, Type C systems do not inhibit water pressure/water ingress but controls water ingress in a strategic fashion.

Grades of Habitable environment 

Table 2 of BS8102:2009 defines waterproofing requirements to achieve desired internal environments. These three Grades are defined as:

 – Grade 1: Where some seepage and damp areas are tolerable – such as car parks, non-electrical plant rooms or workshops.

 – Grade 2: Where no water penetration is acceptable but damp areas are tolerable – such as plant rooms or workshops which require a drier environment than Grade 1.

 – Grade 3: No water penetration is acceptable – such as living spaces, commercial areas, offices, restaurants and kitchens.

It is important the environmental Grade is defined as early as possible, to ensure expectations are achieved from the outset.

In achieving a Grade 3 habitable space – a combination of two types of waterproofing (A & C, B & C) is usually adequate. In most cases the safest combination will always include a Type C system, whilst the choice of the other system is largely dictated by the type of structure/project requirements.

Another important consideration is whether the basement area will extend beyond the ground floor footprint, such as a buried deck or roof area. 

This will also require a waterproofing solution.  In most cases, a combination of a waterproofing system along with a protective drainage layer will be required.  

The steps to a good design solution

A good CSSW (or equally qualified) waterproofing designer will consider a bespoke approach, based on the project criteria.

In choosing the right approach, the design solution should be a process which includes multiple factors such as; customer requirements, standards, robustness, cost, resources, time, skill required, safety, desktop studies, analysis of geotechnical reports/tests and expectations of ground water all translated into a design solution.

Delta’s technical drawings are available in all formats and free of charge – hit the link to take a look!

Leave a Reply

Latest news

Altro

Altro distils style and performance at English Spirit

English Spirit Distillery has used an extensive package of Altro products front and back of house, in their new visitor centre café, shop and viewing area for the working distillery.

Posted in Articles, Bathrooms, Bedrooms & Washrooms, Building Industry News, Building Products & Structures, Building Systems, Case Studies, Floors, Interior Design & Construction, Interiors, Kitchens, Restoration & Refurbishment, Retrofit & Renovation, Timber Buildings and Timber Products, Walls

Abloy

Abloy UK creates bespoke locking solution for Secure Information Boxes

Abloy UK has supplied The Safety Letterbox Company Ltd with a bespoke Sentry CL811 Camlock for use in its Secure Information Boxes, assisting life safety and complying with new regulations and legislation for high rise buildings.

Posted in Access Control & Door Entry Systems, Architectural Ironmongery, Articles, Building Industry News, Building Products & Structures, Building Regulations & Accreditations, Building Services, Case Studies, Facility Management & Building Services, Health & Safety, Posts, Restoration & Refurbishment, Retrofit & Renovation, Security and Fire Protection

CUPA

CUPA: CUPACLAD enhances hotel aesthetics with a creative natural slate façade

Situated at the northern edge of a newly developed retail park near Bristol, the Abbey Wood Travelodge was conceived as part of the company’s new Budget-Luxe line of hotels – it features CUPACLAD, from CUPA PIZARRAS.

Posted in Articles, Building Industry News, Building Products & Structures, Building Systems, Case Studies, Cladding, Concrete, Cement, Admixtures, Facades, Posts, Restoration & Refurbishment, Retrofit & Renovation, Walls

Origin