David McDonald is Education Secretary of the IHBC and is also Chair of London Branch. Until recently he led the Conservation and Design Team at the Royal Borough of Kensington and Chelsea. A graduate of geography and geology, then qualifying as a Town Planner, he worked for a number of years at the London Borough of Camden. While at Camden he completed the AA Diploma in Building Conservation. He is currently an independent historic environment consultant, specialising in providing heritage training for other built environment professionals.

Ptolemy Dean is an architect specialising in conservation work to historic buildings, additions to historic buildings and the design of new buildings in sensitive locations. Ptolemy will also be known as a historic buildings adviser on the BBC2 ‘Restoration’ series. He serves on the National Trust Architectural Panel and Salisbury Cathedral Fabric Advisory Committee and in 2012 became the Surveyor of the Fabric at Westminster Abbey. He is the author of two books on the architect Sir John Soane and ‘Britain’s Buildings, Places and Spaces, The Unseen in the Every Day.’

Allyson McDermott heads her own practice, established in 1980. She has served on the Board of Trustees of ICON, as Chairman of the Historic Interiors group, wallpaper advisor to the National Trust, and head of the conservation studios for Sotheby’s. She is a recognised authority on the conservation and history of Chinese export papers. The practice specialises in the analysis, identification and recreation of historic wallpapers and painted finishes using both modern digital and traditional printing and painting techniques for such clients as Historic Royal Palaces, The Royal Household, National Trust, English Heritage and Historic Scotland.

David Drewe has been at English Heritage since 1998, joining as a Senior Mechanical and Electrical Engineer in the then M&E Team. He is now Head of the Building Services Engineering and Safety Team, which comprises specialist professional Building Services Engineers; fire, security and H&S Advisers and emergency and business continuity Planning Managers. His work includes providing advice and developing standards and guidance relating to building services engineering, environmental and sustainable develop­ ment issues and the relationship and impacts that they have on historic building interiors and structures. Prior to joining English Heritage he worked for a number of organisations including London Transport and the Rank Organisation.

Ylva Dahnsjö is a Consultant Conservator for the National Trust London and South East Region, where she is responsible for a portfolio of over 30 properties. During 27 years in the conservation profession she has amassed experience of many different ways of nurturing heritage in various cultures. Prior to joining the National Trust, she ran a conservation studio for Dundee University, where the architectural drawings of Charles Rennie Mackintosh and Alexander Greek Thomson, and the town plans of Patrick Geddes were all treated. She is a former Chair of the Scottish Society for Conservation and Restoration and Vice Chair of the National Council for Conservation­Restoration, the body that established the Institute of Conservation (Icon). She is also a Fellow of the Linnean Society

Neil Burton is an architectural historian. He worked as an historian in the Greater London Council Historic Buildings Division and then at English Heritage as an Inspector of Historic Buildings, first with responsibility for church cases in the north of England and later for all types of buildings in the East Midlands. More recently he was Secretary of The Georgian Group. He has published a number of works on historic buildings including Life in the Georgian City with Dan Cruikshank and Behind the Facade: London House plans 1660–1840 with Peter Guillery. For the last decade he has been a director of The Architectural History Practice Ltd.

Caroline Rye works as a researcher and consultant specialising in monitoring the performance of older buildings. Alongside Cameron Scott she leads ArchiMetrics Ltd, a company which measures many aspects of building performance including fabric and ventilation heat losses, indoor air quality and moisture behaviour; in particular interstitial condensation. She has undertaken extensive research work on behalf of the SPAB looking at solid wall U­values and refurbished traditional buildings. She is the author of three SPAB Research Reports as well as a lead contributor on the STBA ‘Responsible Retrofit’ (Gap Analysis) Report. She has also been consulted by Historic Scotland, English Heritage, Kevin McCloud, B&Q and Trinity College, Cambridge.

Michael Jones is Director of Project Management for The Portman Estate and has been involved in its ongoing redevelop­ ment for the last six years. A Chartered Building Surveyor by qualification, he is responsible for the Estate’s sustainability policy and has recently seen this expand into a fuller CSR strategy. The Portman Estate covers 110 acres of London’s West End and owns 350 Grade II listed buildings, predominantly from the Georgian period. The Estate takes an increasingly active role in managing both the properties and the local environment. Protecting its heritage value while providing modern property facilities is an ongoing challenge.

Paul Drury has been in private practice since 1997, currently in the Drury McPherson Partnership. Previously he was Director of English Heritage’s London Region. He has some 25 years experience as a Chartered Surveyor, archaeologist and architectural historian in both the public and private sectors, and in the past decade has been particularly involved in heritage policy development, including the English Heritage Conservation Principles (2008). His personal research interests range from medieval floor tiles to Tudor and Stuart great houses; Hill Hall: A Singular House Devised by a Tudor Intellectual was published in 2009.

Gary Butler trained as a bricklayer then studied architecture at Leicester Polytechnic and Cambridge University. He was introduced to conservation practice in the early 1980s at Julian Harrap Architects where he was responsible for the repair of S S Teulon’s brick extravaganza at St Mark’s, Silvertown. He was a Principal Lecturer at Kingston University and until 2005 also taught architectural design at Cambridge University. He is both an AABC and RIBA accredited conservation architect and together with his wife, has led Butler Hegarty Architects since 1993. Gary teaches traditional building construction and repair techniques as part of the Conservation Foundation Degree at the Building Crafts College, Stratford.

John Simpson graduated from Heriot Watt University in Edinburgh in 1986 before relocating to Norway. He returned to the UK in 1993 with Neils Torp Architects as project architect on the British Airways HQ Waterside, near Heathrow. Following the BA project John joined RHWL Architects, the executive architects for Waterside, where he has been responsible for many projects including the Royal Bank of Scotland HQ campus at Gogarburn near Edinburgh and the renovation of St Pancras Chambers. John is now a Director at Ushida Findlay Architects who are responsible for the Orbit tower at the Olympic Park as well as other avant­garde projects in the UK, middle and far­east.