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

Vent-Axia

Vent-Axia Enables Action this World Ventilation Day

Leading ventilation manufacturer Vent-Axia is welcoming the third, World Ventilation Day (#WorldVentil8Day). This is a day dedicated to recognising and promoting the importance of ventilation and indoor air quality (IAQ).

Posted in Air Conditioning, Articles, Building Associations & Institutes, Building Industry Events, Building Industry News, Building Products & Structures, Building Regulations & Accreditations, Building Services, Facility Management & Building Services, Health & Safety, Heating, Ventilation and Air Conditioning - HVAC, Posts, Retrofit & Renovation

Hush

Noisy boardroom fixed using Hush Absorber panels

Hush Acoustics has completed a project to improve the acoustic environment much closer to home than usual by installing its high performance Class A sound absorber panels within its HQ boardroom.

Posted in Acoustics, Noise & Vibration Control, Articles, Building Industry News, Building Products & Structures, Building Services, Case Studies, Ceilings, Facility Management & Building Services, Restoration & Refurbishment, Retrofit & Renovation, Walls

EPD

EPD Insulation Group finalist for the Peterborough Telegraph Business Excellence Award

EPD Insulation Group, an independent family-run distributor, is a finalist in the prestigious Peterborough Telegraph Business Excellence Awards.

Posted in Articles, Awards, Building Industry Events, Building Industry News, Building Products & Structures, Building Services, Insulation, Posts, Restoration & Refurbishment, Retrofit & Renovation, Walls

Freefoam

Freefoam supports crucial lifeboat build in Wales

Freefoam Building Products has helped complete the build of a new garage for a crucial lifeboat service in Carmarthen, Wales.

Posted in Articles, Building Industry News, Building Products & Structures, Building Systems, Case Studies, Cladding, Fascias, Restoration & Refurbishment, Retrofit & Renovation, Roofs, Walls