Purposefully-piped water goes back at least to the Bronze Age in the second millennium BC. In later times, hot water use was a normal part of Roman construction technology for comfort in buildings. That said, it is surprising that the implementation of this ancient technology hasn’t been entirely resolved and that it is a subject most people have a position on, irrespective of working in the field of construction.
When budget is not the key consideration, why do radiators often stand out as a troubled subject for discussion? Setting aside the basic technical skill required to size up, specify and install a radiator correctly and in compliance with regulations, other factors outside the discipline of building services come into play. Unlike most mechanical plant, radiators are not confined to ceiling voids and plant rooms.
Instead they are right in the field of vision (in interior design terms), and distinctly present in our awareness when they fail to operate on a wet, cold, windy day. Every member of the design and construction team could tell you a troubled story! Let’s look at the situation from their respective perspectives.
Taken from an M&E viewpoint, the architect finds a “sensational radiator” and presents it to the client using masterful persuasion about the interior aesthetics, the sight lines, the furniture layout and how many options are available in the RAL colour swatch. As you roll your eyes to the ceiling, this beautiful slim, light radiator (an artwork) is “sold” to the client to complement the room decor. The problem is it doesn’t necessarily provide the required heat output, carries an additional cost to re-paint, is not what the sub-contractor tendered and anyway won’t arrive on time because the MC has squeezed the commissioning window! Whereas the architect may be delighted with it, only time will tell if it functions adequately for the end-user.
From a quantity surveyor’s viewpoint, the architect is nearly always at fault for driving up costs and delaying the programme because of the care and control they wish to exert over the radiator selection. Anecdotally, it once led a sub-contractor to declare to an architect at a site meeting that “painting radiators lowers heat output and efficiency”.
Was this the same mechanical sub-contractor who “forgot” to price and plan for the colour change? It may have been included in the architect’s specification but it was not coordinated with the M&E tender documents. The truth of the matter is that beautifully-designed radiators, which function well and complement interiors, are available in an array of colours and design shapes at competitive prices. It only requires care and attention to shop around and source the appropriate fitting in time.
The anecdotal architect’s response, having not received a sales visit from a radiator supplier in 15+ years of practice, is to unashamedly “google” supplier names from cheap lookalike designed models after which a model is settled upon. High drama next ensues on site to achieve the “colour by number radiator placement” in the correct place. Then the architect’s snagging begins, picking up a lack of protection during construction, carelessness in the installation, and paint drips courtesy of Mr Painter on site.
Problems with radiators discovered at snagging stage are legendary but this one is the most amazing I’ve come across. Before the glue had a chance to dry, the architect discovered a most cunning plan to avoid a co-ordination issue. A total of 132 perimeter radiators were fixed with 528 sawn-off bolts, glued to the vinyl floor. Yes, the radiators were actually only supported by their pipework and glue-fixed onto vinyl because the M&E coordinator on site must have been too nervous to raise the issue of bolt-fixing through the steel flange of the perimeter beam!
But so much for the architect’s response, what about the end-user experience? Radiators can create hotspots and draughts, dry the air (especially electric storage heaters), interfere with furniture layouts and curtain lengths, become air-locked at least twice a season and are difficult to clean (we’re talking fluff!). That said, they are good for drying wet washing in damp, rainy weeks or of course you can screen them with DIY store radiator covers. I accept that the profile of this end-user is probably somebody who doesn’t benefit from top-of-the-range controls, remote energy management applications (as utility companies are now promoting) and anything above the minimum specification.
For those who don’t always get along well with radiators, there is comfort in the move towards better-insulated houses, affordable underfloor heating and Passive Haus (now adopted by DLRCC and soon to be followed by other county councils).
The traditional radiator mounted on a wall below the windowsill may lose its prominence, just as the traditional hot press disappears in a properly-insulated home. Similarly, the commercial viability of 4-port fan coil units is leading to the trend of stripping out banks of radiators and providing heating and cooling from a single source at ceiling level.
However, for the rest of us radiators will not be eliminated as long as our day-to-day heat-producing activity within the building is less than the heat loss through the building fabric, vents and chimneys. The appended list of considerations below is non-exhaustive but may prompt further thought when designing for space heating.
There are three main challenges to radiator representatives who understand the intricate links between design and performance so that they aid better coordination of the design, specification and installation. These are as follows:
(1) Visit more architects with glossy brochures and teach them about sizing for new regulations and building standards. Leave them in a position to understand heat loss calculations and sizing of appliances for themselves. They will teach you about design and commercial trends.
(2) Visit building services engineers, adding a new dimension to the visit. Teach them about design, colours and materials. Explain to them what architects want and check that what is tendered is correct and agreed by all designers.
(3) Prepare CPD courses to up-skill the industry in design and installation fields.
In addition to the foregoing, all involved in the process should also consider the following.
Selection — Consider the energy source and the environment;
— Options for heating appliances;
— Energy efficiency and COP;
— Comfort;
— Controls;
— Materials: painted mild steel, cast iron, stainless steel, flat panel aluminium and, more unusually, clear and mirrored glass (13mm thick toughened glass) and glass panel fronts;
— Budget: Installation costs v maintenance and replacement costs, warranties and lifespan, import costs, currency differences, non-standard orders and lead times, certainty of fuel costs and fluctuations when oil prices (due to demand) or resource reserves alter.
Regulations and guidelines – Take account of protected structures and conservation;
— Building Regulations and TGD Part L: Conservation of Fuel and Energy;
— European Normative Codes: e.g. BE EN 442 European Standard for Radiators/CE Certification;
– CIBSE Guide A Environmental Design 2015 Edition;
— CIBSE Radiator Product Data Templates (PDTs);
— CIBSE Guide H Building Control Systems;
— CIBSE Guide M Maintenance Engineering and Management;
Safety — Consider by-products and emissions from the combustion process and venting to the outside, e.g. CO from gas boilers and solid fuel boilers, CO2 and moisture build-up, ash from solid burners, cleaning of flues and monitoring of toxic emissions;
— Potential hazards from leaks, spills and burns;
— Safety issues and requirements for LST (low surface temperature) radiators in schools, creches, hospitals and nursing homes;
— Safety of toughened glass on radiators;
— HSA Guideline: Health and Safety at Work in Residential Healthcare Facilities;
— HSA Guideline: Safety with Lead at Work.
In conclusion, radiators may be small building components but they are vital to the heating solution and deserve detailed consideration at the design, specification and installation stage. ■