CRL Restoration

Innovation

One of the cornerstones of our business success has been our commitment to innovation. Each year we invest in the development of new techniques and materials for our specialist market sector which enable us to provide innovative engineering solutions for the benefit of our clients.

We work closely with industry leaders to help them in their research programmes by providing industrial support and access to our sites for evaluation of the research output.

These are recent examples of our innovation both in techniques and materials.

Hot-Mixed Lime Mortars

Hot-mixed lime mortars has become a much talked about topic in the last 3(three) years and CRL Restoration have been at the forefront of advocating the use of hot-mixed lime mortars and disseminating the information that is becoming available to people in the industry.
To this end, CRL Restoration have held 3(three) hot-mixed lime mortar days this year for our clients, conservation architects, surveyors, stonemasons and our own staff. These days have been held in conjunction with Nigel Copsey of the Earth Stone & Lime Company and Associates. Nigel is an eminent authority on hot-mixed lime mortars and a strong advocate of their use.

At Reading Abbey ruins where a NHL 3.5 was specified for carrying out the consolidation works on the ruin walls, CRL Restoration approached the architects for the works and recommended that hot-mixed lime mortars be used instead. After attending one of our hot-mixed lime mortar days they were convinced that it was the right material/method of mixing to be used and the specification was changed.

Comments from the conservators on the project include:-

“It is truly a lovely material to work with. Even replacing flints in the wall overhangs is not a problem, the bond between all the elements is phenomenal.”

“We could never have carried out the types of repairs which we are doing with a NHL mortar.”

Cathodic Protection of Steel Framed Structures

Impressed Current Cathodic Protection (ICCP) has been around since the early 19th Century to control corrosion in structures. Well designed and expertly installed ICCP will stop any further corrosion occurring. When cathodic protection was first introduced as a means of stopping corrosion of the steel frames in high rise buildings in 1991, CRL embraced the technology and always at the forefront of innovation, became the first company to successfully use this technique on an existing heritage structure. This took place on a commercial contract at the Government Building in Dublin where two steel beams in the colonnade had begun to corrode causing the stone facing to crack and fall off.

CRL were also the first company to install a cathodic protection system to a complete building. This took place on the terracotta facade of the Gloucester Road Tube Station.

Since that time CRL have been actively involved with the improvement of the systems, techniques and standards, and have gone on to install Cathodic Protection systems on numerous historic buildings throughout the UK.

Carbon Fibre Strengthening of Heritage Structures

CRL was the first company in the UK to use FRP composites for strengthening structures in 1996. We have played a key role in developing the technique and assisted with the development of standards and guidance documents for the design, installation and management of composite systems published by the Concrete Society as Technical Reports 55 & 57. We provide the construction industry with innovative strengthening techniques using FRP composite materials which comply with current Eurocodes.

FRP composite strengthening lends itself to conservation works bearing in mind the ‘minimal intervention’ principle stressed by Historic England, and as such CRL Restoration have recommended and carried carbon fibre strengthening works on variouys heritage structures in recent years.