Consultancy & Education

This section of our site is aimed at industry professionals and students who are looking carefully at various detailed design aspects of a swimming pool project. We have produced some generic details which can be downloaded in PDF form to help inform the design process. These details should not be used without proper further consideration of the site-specific elements.

Light Fittings and Wall Penetrations

A) Every fitting that penetrates a concrete pool shell should have a puddle flange integrated within the first fix pipe.

B) The puddle flange detail should be augmented with a hydrophilic strip which should be designed specifically with the amount of concrete cover in mind. The hydrophilic strip should also not risk compromising the fitting itself. NB: some hydrophilic strips expand with considerable force and therefore manufacturers should be consulted.

C) Where possible fittings should be cast in or sprayed around to ensure good adhesion between the first fix pipework and the surrounding concrete. Care should be exercised in accordance with good practice to avoid honeycombing. The practice of cutting core holes from a completed concrete pool shell whilst having the benefit of neatly locating first fix pipework in the desired position introduced a further slip joint which can be prone to leaking over time.

D) Utilise products that are specifically designed for swimming pools. This is particularly applicable to lights. There are a wide variety of light fittings available, some of which claim to be IP Rated but care should be exercised to ensure that fittings are swimming pool specific and that the IP rating is understood. For example, an IP rating of 67 whereby 6 = mechanical protection and 7 = water ingress protection – superficially sounds acceptable to most pool designs but the later digit reflects a 30 minute water immersion test which is not sufficiently robust for a pool environment where in addition to constant pressure there are also forces to be dealt with relating to thermal expansion and different co-efficiency of thermal expansion, which will come in to play over the life of the pool.

Example Detail

The detail here sets out some of the above principles and is in common use within the industry:

Warm Roof Construction

The construction of a roof over a swimming pool is significantly more complex than a similar construction over a domestic dwelling or ancillary building. The condition is further exacerbated if an automatic cover is not installed. Uncovered pools are common in commercial situations but less common at a domestic level. If you are designing a warm roof over an uncovered domestic pool extreme caution is advised and it is prudent to engage a checking consultant to verify that your proposed detail accords with good practice and the various standards. In our experience designers have been caught out in the following ways:-

A) Simply installing the wrong type of roof construction for the wrong environment.

B) Failure to take on board the importance of penetrations through a vapour check.

C) Failure to co-ordinate the roof design at key junctions, allowing vapour to permeate from one roof void into another.

D) Not checking the construction drawings.


Anyone responsible for designing a warm roof should familiarise themselves with the basic scientific principles behind interstitial condensation. It is not intended to provide an exhaustive resume of this well understood topic here, suffice to say that moisture penetrates out at the dew point and when that dew point is within the fabric of a building catastrophic consequences can ensue. The images below illustrate an uncovered domestic pool after only c. 15 years of life. Left unchecked this roof would have experienced extreme structural failure and probably collapsed within 2-3 years. The cost of rectification was circa £200,000.00.

Pool Architecture

Typical Section

The typical sections below have been used on countless of our indoor pool designs with subtle variations to suit the site conditions. Its strengths are the integration of a continuous vapour check which has a well understood resistance to vapour pressure and meets the target of vapour resistance level of 43000 MNsg NB: not all products hit this level. Its weaknesses principally revolve around the risk of cracking if inadequate fixings are used and its inability to accommodate any penetration for lights, ducts etc [ lights can be recessed into the plasterboard ceiling without compromising the VB ]. It also inevitably results in a fat fascia and soffit detail which needs to be reconciled against any planning drawings.

Process Pool Architecture

Monarflex Reflex 275

Moveable floors within indoor pools and the impact on the climate control system

Moveable floors are becoming increasingly popular. Notwithstanding the considerable capital outlay in sites where space is confined or where a dual use has substantial benefits they clearly confer significant advantage. One topic that is overlooked with moveable floors on an indoor pool installation is the air handling requirements for the different uses of space in the raised position.

In 2015, for example, we undertook a school pool refurbishment and the brief from the head was to be able to use the space when the floor is raised for both teaching in exam mode and separately as a gymnasium. Toggling between these conditions requires a careful analysis of both the requirement for the pupils in different modes and the duration between each mode to enable site based staff to properly plan any transitions. The attached pdf spreadsheet shows the potential complexity.

This switching between modes is easily overlooked and must be planned as part of any detailed design process.

Process Pool Architecture

Working draft for comment and co-ordination

“I have worked with Mark Saxton on a number of high quality domestic refurbishment pool projects and find his knowledge of both products and design far exceeds that of other pool designers and contractors. His sense of style, his expertise and attention to detail mean that our most fastidious clients are overjoyed with the end result.”

James Slater – Building Surveyor and Designer | Spring 2008

Consultancy & Education Pool Architecture