Heritage Conservation Consultancy & Specialist Conservation Contracting
Specialist conservation consultancy, condition surveys, material investigation, technical reporting and traditional conservation works for historic buildings and architectural fabric.
Michal Kosciak
MSc Building Conservation | MFA Sculpture
Director & Conservation Consultant
Over 25 years of professional experience in the conservation of historic buildings, traditional materials and architectural heritage.
Read more about me →Our Services
Heritage Consultancy
Conservation reports, condition surveys, heritage assessments, specifications and specialist technical advice for historic buildings and protected structures.
Learn more →Material Investigation
Investigation and assessment of traditional materials including stone, lime mortars, terracotta, Coade stone, historic concrete, plaster and renders.
Learn more →Conservation Contracting
Specialist conservation and repair of stone, masonry, lime mortars, decorative plaster, terracotta, Coade stone and historic architectural fabric.
Learn more →Conservation Project Management
Specialist management, site supervision, quality assurance and coordination of conservation and heritage works.
Learn more →Featured Project
Ambassador Theatre, Dublin
Condition Survey & Material Investigation of the Historic Coade Stone Frieze
Specialist investigation, sampling and analysis of Coade Stone elements to support conservation planning and decision-making.
About KHC Ltd
KHC Ltd was founded by Michal Kosciak MSc, MFA, a conservation professional with over 25 years of experience in the conservation of historic buildings.
Combining practical craftsmanship, academic research and project management expertise, KHC delivers sensitive, evidence-based solutions for our built heritage.
Qualifications & Memberships
MSc Building Conservation
University of York / Weald & Downland
MFA Sculpture
University of Rzeszów
Specialist Training
West Dean College & international experts
ICRI Ireland
Institute of Conservation
SPAB Ireland
Society for the Protection of Ancient Buildings
Building Limes Forum Ireland
Member
Repairs and Use of Lime in the Restoration of Rockville House, Ballsbridge, Dublin
Journal of Building Survey, Appraisal & Valuation · Vol. 14, No. 2 · 2025
View publication →Why work with KHC?
01
Evidence before intervention
Investigation, sampling and analysis come first, so repair decisions rest on what the fabric actually is.
02
Consultancy and contracting
Advice and hands-on works under one roof, so specifications are written by the people who can execute them.
03
Traditional materials
Lime, stone, terracotta and decorative plaster handled with the techniques the buildings were built with.
04
Documented throughout
Every survey, sample and repair recorded in reporting that stands up to planning and statutory scrutiny.
Discuss a historic building with us
Send the address, a few photographs and what concerns you. We will tell you what investigation the building needs before anything is specified.
What we do
Our Services
Specialist heritage conservation consultancy and contracting, combining condition assessment, material investigation, technical reporting and traditional conservation practice for historic buildings and architectural fabric.
Heritage Consultancy
Specialist conservation consultancy for historic buildings and architectural fabric, including condition surveys, material investigation, conservation reports, heritage assessments, repair specifications and technical advice for owners, architects, conservation professionals, local authorities and contractors.
Typically includes
Condition surveys and defect diagnosis
Material investigation and assessment
Conservation reports and method statements
Heritage assessments and technical advice
Repair specifications and schedules of work
Material Investigation
Investigation and assessment of traditional building materials — including stone, lime mortars, terracotta, Coade stone, historic concrete, plaster and renders — to understand existing fabric, deterioration and previous interventions, and to inform appropriate conservation and repair strategies.
Typically includes
Material identification and condition assessment
Sampling programmes and laboratory coordination
Mortar analysis and compatible lime mix design
Paint, coatings and finishes investigation
Technical reporting and repair recommendations
Conservation Contracting
Specialist conservation and repair of historic building fabric using appropriate traditional materials, techniques and conservation-led methods, with particular expertise in stone, lime mortars, masonry, decorative plaster, terracotta and architectural detail.
Typically includes
Stone cleaning, conservation and indent repair
Lime mortar repointing, rendering and traditional finishes
Masonry and historic brickwork repairs
Decorative plaster, stucco and moulding conservation
Terracotta, Coade stone and cast stone conservation
Sample panels and trial repairs
Conservation Project Management
Specialist management, coordination and supervision of conservation works, from initial investigation and planning through implementation, quality control, completion and final record.
Typically includes
Programming and coordination of specialist conservation trades
Site supervision and workmanship inspection
Quality assurance against specifications and approved methodologies
Coordination with clients, architects, engineers and specialist contractors
Progress reporting and photographic records
Completion records and maintenance recommendations
Traditional Craftsmanship
Traditional craft skills applied to the conservation and accurate repair of historic architectural detail, informed by an understanding of original materials, historic techniques and sculptural form.
Typically includes
Hand carving and modelling of replacement details
Moulding, casting and running of decorative enrichments
Reproduction of historic profiles and architectural details
Matching historic surface finishes and textures
Traditional craft demonstrations and site toolbox talks
Not sure which of these your building needs?
Selected work
Projects
Investigation, reporting and hands-on conservation on historic buildings and architectural fabric. Further case studies are in preparation.
Featured project
Ambassador Theatre, Dublin
Condition Survey & Material Investigation of the Historic Coade Stone Frieze
Kojak Heritage Conservation Ltd carried out a detailed condition survey and material investigation of the historic decorative frieze surrounding the upper drum of the Ambassador Theatre, Dublin.
The investigation included close visual examination from scaffold level, high-resolution photographic recording, endoscopic inspection of concealed cavities and fixing details, comparative material assessment, condition recording and representative sampling for subsequent laboratory analysis.
The survey distinguished three principal phases of material: original eighteenth-century Coade Stone, later carved limestone replacements (probably Portland Stone), and modern cast replacement elements. Historic and later fixing systems were also investigated and recorded.
The findings were presented in a detailed technical report providing a permanent baseline record of the frieze and an evidence base for conservation planning, repair specification and future intervention.
Building
Ambassador Theatre, Dublin
Heritage fabric
Late 18th-century Neo-Classical decorative frieze
Service
Condition survey & material investigation
Methods
Scaffold inspection, photography, endoscopy, material assessment & sampling
Materials identified
Original Coade Stone, carved limestone & later cast replacements
Areas of work
Lime mortars & repointing
Mix design matched to the original mortar, applied in traditional lime repointing and rendering.
Decorative plaster
Conservation and reinstatement of enrichments, cornices and mouldings in lime plaster.
Stone conservation
Cleaning, consolidation, indent repair and carved replacement of decayed masonry.
Terracotta & Coade stone
Identification and repair of cast and moulded materials, including historic artificial stones.
About
About KHC
Heritage conservation consultancy and specialist conservation contracting, combining over 25 years of practical experience with academic research and evidence-based conservation.
Michal Kosciak MSc, MFA
Director & Conservation Consultant
KOJAK Heritage Conservation Ltd is a specialist heritage conservation consultancy and conservation contracting practice providing professional advice, condition surveys, material investigation, technical reporting and specialist conservation works for historic buildings and architectural fabric.
KHC Ltd was founded by Michal Kosciak, a historic buildings conservator with over 25 years of professional experience in the conservation of historic buildings, traditional materials and architectural heritage.
His work combines hands-on conservation practice, specialist craftsmanship, material investigation, technical reporting and conservation project management with academic research and evidence-based decision-making.
Michal holds an MSc in Building Conservation from the University of York, undertaken through the Weald & Downland Living Museum, and a Master of Fine Arts (MFA) in Sculpture from the University of Rzeszów. He has also undertaken specialist professional training at West Dean College and with leading practitioners in traditional plasterwork, scagliola, stucco and historic masonry techniques.
This combination of practical experience, material knowledge and academic research informs KHC’s approach: understand the building and its materials first, intervene only where necessary, use compatible traditional materials and techniques, and clearly record the work undertaken.
How we work
01
Investigate
Survey, sample and analyse before any repair is proposed. What the fabric is determines what can be done to it.
02
Specify
Set out compatible materials and methods in writing, with the minimum intervention the condition allows.
03
Execute
Carry out or supervise the works with conservators trained in traditional techniques, on sample panels first.
04
Record
Document what was found, what was done and what was deliberately left alone, with maintenance advice.
Writing & research
Publications
Peer-reviewed and technical writing on lime, historic materials and the repair of Irish and British building fabric.
Peer-reviewed journal article
Repairs and Use of Lime in the Restoration of Rockville House, Ballsbridge, Dublin
Michal Kosciak & Josephine Walton
Journal of Building Survey, Appraisal & Valuation · Vol. 14, No. 2 · 2025
DOI: 10.69554/UCHO9197
A detailed conservation case study of Rockville House, a protected Victorian building in Dublin. The paper examines the building's historic fabric, material deterioration and previous incompatible repairs, and documents the conservation approach using traditional materials and techniques.
The study covers historic brickwork and lime mortars, Irish wigging pointing, stone and decorative elements, structural masonry repairs and the reinstatement of significant architectural features.
View publication →Also available
Conference papers, technical notes and reports are available on request. For a copy of a specific report or a reference for published work, please write to us.
Education, training & membership
Qualifications
Formal conservation education, specialist craft training and continuing professional development, supported by active membership of recognised conservation and traditional building organisations.
Education
MSc Building Conservation
University of York / Weald & Downland Living Museum
Building conservation, conservation philosophy, building pathology, historic materials and conservation practice.
Master of Fine Arts (MFA), Sculpture
University of Rzeszów
Fine art and sculpture, including modelling, carving and casting — skills directly applicable to the conservation and reinstatement of architectural and decorative detail.
Specialist Training
Scagliola & Stucco Marmo
Maurizio Feliziani — Scagliola & Stucchi d'Arte
Intensive specialist course in traditional scagliola and stucco marmo techniques.
Traditional Irish Wigging / Tuck Pointing
Dr Gerard C. J. Lynch
Specialist training in historic Irish brickwork finishing and traditional wigging pointing techniques.
Understanding Elizabethan Plasterwork
Philip Gaches
Specialist training in historic decorative and Elizabethan plasterwork techniques.
Conservation of Historic Concrete
West Dean College
Specialist training in the assessment, conservation and repair of historic concrete.
Structural Repair of Historic Buildings
West Dean College
Training in the diagnosis and appropriate structural repair of historic buildings.
Conservation and Repair of Stone Masonry
West Dean College
Specialist training in traditional stone masonry conservation and repair.
Memberships
ICRI Ireland
Institute of Conservator-Restorers in Ireland
SPAB Ireland
Society for the Protection of Ancient Buildings
Building Limes Forum Ireland
Member
A full professional CV, including conservation experience, selected project references, specialist training and published research, is available on request.
Enquiries
Contact
Tell us the building, the element you are concerned about and what stage the project is at. Photographs are always useful.
Kojak Heritage Conservation Ltd
Office
51 Wellesley Manor
Bettystown, Co. Meath
A92 P2H7, Ireland
Telephone
+353 87 686 6867Enquiries
Monday to Friday, 9am – 5.30pm
Site visits by arrangement
Working across
Ireland and the United Kingdom, with survey and consultancy work undertaken further afield by arrangement.