John Doyle Construction, part of the John Doyle Group, specialises in the construction of substructure, superstructure and infrastructure projects. Stef Stefanou is the firm’s urbane chairman.

Is the concrete frame market healthy?

It is in a reasonable shape. It’s not over spilling with work, but there is sufficient volume of projects. Concrete framework has been steadily gaining ground on steel over the past two years. This is because steel prices have risen sharply and because concrete frames are ideal for residential schemes due to their thermal and acoustic mass. The most buoyant sector of the market, and it has been for two years, is high-rise residential – everybody is going crazy for flats at the moment.

What advantage does a concrete frame have over steel?

Concrete is far more flexible than steel – because we do not have to order in pre-formed sections in advance concrete construction allows clients more time to change their mind.

What is the lead time for a concrete frame contractor?

The lead time is about five or six weeks, it depends on how much reinforcement detailing we have to do.

How are rising prices for reinforcing steel affecting the concrete industry?

Reinforcement is more pricey than before and it is more difficult to ensure a supply, no job of ours has suffered as a result of the shortage, but it is a worry. Where clients are looking for a fixed price, lump sum cost, price uncertainty is an issue so we have to tie suppliers to a figure. Also getting certain sizes of rebar is a problem.

Is the labour shortage an issue?

There is always room for good, skilled labour. It is fashionable to say there is a shortage of labour – but the situation is not as dramatic as people make out. Yes, we need to train more people.

I know it sounds arrogant but I don’t think we’ve suffered.

What is your preferred method of procurement?

We prefer partnering and we like to be involved at the beginning of a project to influence the details, to value engineer the scheme and to make it buildable. That way everybody benefits: the client gets a cheaper scheme; we get a project we can construct on time; and the designers get a scheme that can be built.

Are there any developments that you think will affect concrete frame construction?

Self-compacting concrete is an exciting development – we’ve used it on a number of contracts. Five years ago in Japan, 22% of all projects used self-compacting concrete – in the UK it was 2%, but that’s changing. It is ideal for difficult applications. The biggest drawback is cost. We’re working on research to produce a standard for this type of concrete. With self-compacting concrete quality systems are vital and when you cure it, you have to do it well.

Another development is precast/insitu hybrid construction. This uses a mixture of precast and components and concrete cast on site.

It reduces construction cycle times, improves quality and it uses less rebar.

What is the best concrete-framed project in the UK?

We are proud of what we’ve achieved at Albion Wharf. We call it the “Doyle Building” because of the amount of work we put in to ensure the building’s raking concrete-supporting legs were properly constructed.

How can a client ensure that the concrete contractor they are appointing is competent?

They should appoint a SpeCC registered contractor, which is a registration scheme for specialist concrete contractors that we belong to.

  • Details of the scheme are available on the SpeCC website,

Concrete frames