Conservation teams are responsible for the preventive and remedial treatments and scientific investigation of objects. This is achieved through expert knowledge of the science of materials and practical expertise in conservation. An architectural model may need to be conserved for several different reasons, such as poor environmental conditions in storage, mishandling or neglect, or due to inferior material components applied in production. Remedial conservation is undertaken to improve the condition of the collections, ensuring their long-term stability. Through scientific analysis and knowledge of production and conservation procedures, the conservator can interpret object deterioration and apply suitable treatments.
Unless on permanent display, many models will remain in storage for most of their lifetime. There are many complex obstacles to overcome in terms of the storage or architectural models such as the model size, weight, material make up, fragility to movement, mechanical aspects and susceptibility to environmental fluctuations. The quality of storage is the most important factor in safeguarding the lifespan of a collection. Collection objects should also be monitored, and planned storage improvements implemented to ensure that a long-term preservation strategy is met. Guidance should be sought within these subject areas prior to selection of a storage facility:
- Location: external and internal
- Construction and building specifications, materials
- Risk assessment and hazard identifications
- Security and access
- Environmental stability and sustainability
- Pest infestation and monitoring
- Fire prevention and protection
- Water ingress prevention
Case Study: ‘Storage of the Architectural Models Collection at the Royal Institute of British Architects’
Lisa Nash, RIBA Conservator
The RIBA collections are housed in enclosed areas designated for the sole purpose of collection storage, in conditions intended to preserve. For any organisation with a collection, storage is the principal factor in ensuring the preservation of objects as they will spend most of their life-span within this facility and not on display.
The RIBA architectural model collection currently comprises at 380 objects and is split between two stores; the RIBA store located at the V&A Museum where our smaller models are housed and at our collection out-store where many of our larger, heavier models are located.
Key objectives for the RIBA when considering storage spaces for the models:
- The store should be appropriately located and suitable for access.
- The storage area should provide proper support for its contents, and have the capacity for collection growth.
- The spaces should be secure. All storage doors are required to be lockable and keys or swipe cards issued to strictly control any unauthorized access.
- No windows are to be situated in any of the designated storage areas.
- An Integrated Pest Management and cleaning program is in place.
- Staff are taught handling and cleaning techniques in line with conservation guidelines for objects in storage.
- The air could be circulated through high density filters to remove harmful atmospheric pollutants.
- All objects are clearly labelled with the collection number, to ensure they can be tracked and retrieved.
- A maintenance programme was in place to test systems and determine planned improvements.
Shelving and materials within the storage space:
The RIBA architectural model storage area is designed to be as uniform as possible, to allow good air circulation around the objects with the shelving systems positioned to ensure adequate aisle access for staff and cleaning. The lowest shelves are raised at least 10cm off the ground in case of water ingress with leak detection in place. The storage has designated areas that are kept clear to assist decant during retrieval to minimise risks of damage during handling. The largest models are placed on the lower shelving to ensure that retrieval is manageable.
Static shelving is used to prevent risk of damage from the movement and vibration a mobile shelving unit could potentially cause. All shelving is metal, in accordance with current guidelines and not wood, to avoid chemical off gassing which could potentially harm the collection. Objects are subject to chemical exchanges with ancillary materials and those near or touching objects can often be hazardous. Therefore, materials used in the surrounding storage environment, such as paints, adhesives and building materials can pose a risk to the collections so these should be chemically inert. Some objects due to their own material make-up can be a risk to other objects through off-gassing during deterioration and special requirements may have to be met.
Any new materials must be tested for their suitability using the British Museum’s Oddy Tests and existing material should be retested after five years. An Oddy test initially developed by Andrew Oddy and colleagues at the British Museum in the 1970’s is an accelerated corrosion test that can help to predict whether particular materials are safe to use with objects inside enclosed spaces such as showcases or stores.
Boxing, Crating, Transport & Moving:
Crating is necessary to safeguard the object from movement, vibration and the elements throughout transit. Boxing or crating will also protect when in storage from dust and provide a buffer to any minor fluctuations in environmental conditions. Like the shelving, materials used in the construction of cases should be chemically inert and stable for the lifetime of the case.
Wooden packing crates designed for air freight are required to meet the International Plant Protection Convention (IPPC) approved in the international standard ISPM 15 for Wood Packing Materials, 2002. All wooden crates are required to be marked with an authorised stamp stating that all wood packaging materials are non-processed woods.
The markings of a safe crate will include both the IPPC and Forestry Commission logo, the country of origin with the unique registration code stamps and indicate how the pallet was treated as seen in this image (DB= debarked HT= heat treated). Any packing cases are required to support and protect the objects during transit and manage the environment within the case.
Plastazote can be used to pack out the crate or box to protect the models from vibration and movement. Plastazote is a non-toxic man-made lightweight polyethylene foam both tough, non-absorbent to liquids and very flexible, making it a useful tool in the storage and transit of architectural models.
If crating is too expensive and there are space and weight constraints within the storage area, corrugated plastic or corriboard can be used as an alternative to wood or flight cases for housing models. This material is chemically inert, lightweight and both water and impact resistant.
Models should be transported upright and never tipped to access doorways or lifts, even when crated. In transit models must be secured fully by strapping to limit movement, using a vehicle fitted with shock absorption.
New storage areas should be in accordance with BS EN 16893:2018 Conservation of Cultural Heritage: Specifications for location, construction and modification of buildings or rooms intended for the storage or use of heritage collections.
Organic based material readily absorbs moisture from the air, therefore, the control of temperature and humidity is critical in preserving a collection. Unacceptable, fluctuating levels will contribute and increase the rate of breakdown and deterioration of materials as most will expand and contract, causing them to weaken.
Due to the composite nature of many architectural models, the level of humidity is a significant factor, and controlling this will aid in the preservation. High relative humidity will promote harmful chemical reactions and together with high temperature this will encourage deteriorations such as adhesive failure, planar distortions, mould growth and potential pest infestation. Low relative humidity and low temperatures can lead to cracking of woods, embrittlement of materials, flaking of pigments, and structural damage.
Materials can be classified into areas of vulnerability:
- Sensitive to high humidity ≥ 70%: all organic materials.
- Sensitive to low ≤ 35%: organic materials, photographs.
- Fluctuations ≥ 10%: composite objects, parchment, jointed furniture, canvas, decorated surfaces.
Where objects require specific microclimates, this can be achieved using a buffered humidity control material such as ArtSorb® sheets or silica gel. This product controls humidity by taking in moisture when the environment is too humid and releasing moisture when it’s too dry.
To manage the environment in storage the RIBA collections are kept within the following parameters:
- RIBA Out store: 18°C – 21°C, 40 – 45% RH with minimal fluctuations within an hour
- RIBA Stores at V&A: 18°C winter 19°C summer, 45 – 55% set points RH with minimal fluctuations within an hour
Light can also cause irreversible chemical changes in objects. Therefore, the lights are turned off when storage areas are not in use. Ultra-violet radiation is the most destructive form of light and therefore omitted from the storage areas. Daylight is also damaging and is omitted from storage areas.
Pests: types, monitoring, eradication:
Insects will thrive in certain environments, the hotter the conditions the more the insects will feed and breed. Most pests require damp, humid conditions to survive, however some species have differing requirements of food, temperature and humidity, are affected by seasonal climate and type of building. Organic matter such as dirt and debris in and around the shelving will encourage breeding.
Good housekeeping and a routine cleaning programme are therefore vital to prevent pests and damage to collections. Storage areas are often full of dead spaces where insects can flourish. Prevention using an Integrated Pest Management Program (IPM) is the cheapest and most effective form of prevention than using remedial treatments. Blunder traps examined quarterly will enable the conservator to monitor any activity and take action if necessary.
Furniture Beetles (Anobium Punctatum) come under the common name of the powderpost beetle. They are very common in most countries and can infest buildings, wooden objects and furniture, making an architectural model collection vulnerable. The larvae make tunnels through material and can take a 2-3-year period to manifest as adults. In both wood and paper, they emerge through tiny exit holes and leave a small pile of powdery frass that looks like sawdust. The furniture beetle will thrive in cool, damp conditions but not below 55% humidity. The species have four life stages: egg, larva, pupa and adult, the development of the cycle is dependent on the amount of food source, temperature, and moisture. In cool temperatures ≤ 15°C there is likely to be one cycle per year, moderate two per year ≥ 23°C there could be up to five cycles.
Silverfish (Lepsima and Ctenolepisma) are pests always associated with high humidity and damp conditions. They require high humidity of 70-80% to thrive and multiply. They are silver in colour, wingless and are approximately 10-15 mm in length. They feed on glues, inks, starch and mould and can cause an enormous amount of damage to a collection. They create damage that will look like irregular holes or abrasions across the surface. When reaching adulthood, they can live for up to 7 years. Models made using animal glue are very susceptible as they provide a high protein food source.
Monitoring activity will determine whether there is any need for insecticide treatment. Insecticide should be used as a final pest control option as care must be taken not to contaminate and harm the collections. There are other eradication methods such as, low temperature -30°C for 2 days or -18° for 2 weeks or elevated temperatures above 50°C in special Thermo Lignum™ humidity controlled chamber. All treatment options are dependent on the type of object and severity of the infestation.
Handling architectural models can be challenging for many reasons and if mishandled a model can easily incur structural damage.
Model handling can be challenging for many reasons; size, weight, fragility, composite materials and moving mechanical or lighting components. Often constructed using a combined mix of materials such as woods, cardboard, paper, cork, polyamide, acrylic or acrylonitrile butadiene styrene (ABS) and adhered using various glues from animal to synthetic which makes the architectural model vulnerable to both movement and handling.
Staff are taught handling techniques to ensuring that they can recognise any points of potential weakness and types of damage. Condition reports are used by the RIBA to inform the handler of condition, general information on the model; size, weight, material, handling instructions and emphasises any potential areas of weakness.
If stored, transported and handled correctly there is no reason that your architectural models’ collection will not have as long as lifespan possible.
- The UK Wood Packaging Material Marking Programme: Requirements for regulating wood packaging material in international trade ISPM15. The Forestry Commission, Edinburgh 2016
- Selection of Materials for the Storage or Display of Museum Objects (Oddy test), D Thickett and LR Lee, © The Trustees of the British Museum 2004
- British Standards: BS 4971:2017 Conservation and care of archive and library collections (replaces PD 5454:2012 Guide for the storage and exhibition of archival materials)
- British Standards: BS EN 16853:2017 Conservation of cultural heritage. Conservation process. Decision making, planning and implementation
- British Standards: BS EN 16141:2012 Conservation of cultural heritage. Guidelines for management of environmental conditions. Open storage facilities: definitions and characteristics of collection centres dedicated to the preservation and management of cultural heritage
- British Standards: BS EN 16790:2016 Conservation of cultural heritage. Integrated pest management (IPM) for protection of cultural heritage
- British Standards: BS EN 15946:2011 Conservation of cultural property. Packing principles for transport
- British Standards: BS EN 16893:2018 Conservation of Cultural Heritage. Specifications for location, construction and modification of buildings or rooms intended for the storage or use of heritage collections (replaces PD 5454:2012 Guide for the storage and exhibition of archival materials & PAS 198:2012 Specification for managing environmental conditions for cultural collections)
- British Standards: BS EN 16648:2015 Conservation of cultural heritage. Transport methods
- Ashley-Smith, Jonathan, Burmester, Andreas Eibl, Melanie (editors) Climate for Collections – Standards and Uncertainties, Archetype Publications, 2013
- Keneghan, Brenda & Egan, Louise (eds) Plastics: Looking at the Future and Learning from the Past, Archetype Publications, 2008
- Pinniger, David, Integrated Pest Management for Cultural Heritage, Archetype Publications, 2015
- Pyo, Mi Young, Construction and Design Manual: Architectural Models, Dom Publishers, 2012
- Knoll, Wolfgang & Hechinger, Martin, Architectural Models: Construction Techniques Second Edition, J Ross Publishing, 2007
- Karssen, Arjan & Otte Bernard, Model Making: Conceive, Create and Convince, Frame Publishers, 2014
- Ida Antonia Tank Bronken, Susan Braovac, Tone Marie Olstad, Anne Apalnes Ørnhøi (eds) Moving Collections: Processes and Consequences, Archetype Publications, 2012
- Mills, Criss, Designing with Models: A Studio Guide to Architectural Process Models, John Wiley & Sons; 3rd edition, 2011
- Dunn, Nick, Architectural Modelmaking 2e, Laurence King Publishing, 2014
Sweeny, Richard, Paper Sculpture: Fluid Forms, Gingko Press, 2016
- RJ Models https://www.rjmodels.com.hk/architectural-models-guide/
Wattig, Juliane http://blogs.getty.edu/iris/conserving-architectural-models-behind-the-scenes-in-the-research-institute-conservation-lab/ 2013
- Thickett, D and Lee, LR, Selection of Materials for the Storage or Display of Museum Objects (Oddy test), The British Museum, 2014 http://www.britishmuseum.org/research/publications/research_publications_series/2004/selection_of_materials.aspx
Institutes & Organisations
BSI Standards – https://shop.bsigroup.com/
Japanese Museum/Storage of A Models – https://online.archi-depot.com/
Camberwell College of Arts – https://www.arts.ac.uk/colleges/camberwell-college-of-arts/courses/short-courses/conservation-courses
City & Guilds Art School – https://www.cityandguildsartschool.ac.uk/study-here/conservation-bursaries-scholarships/
Getty Institute – http://getty.edu/
ICCROM – https://www.iccrom.org/
ICON Standards – https://icon.org.uk/conservation/conservation-standards
International Academic Projects – https://academicprojects.co.uk/
Lincoln University –https://www.lincoln.ac.uk/home/hh/conservation/
National Conservation Service – http://www.ncs.org.uk/
Northumbria University –https://www.northumbria.ac.uk/study-at-northumbria/courses/conservation-of-fine-art-dtfcfz6/
Preservation Advisory Centre – https://www.bl.uk/aboutus/stratpolprog/collectioncare/
West Dean College – https://www.westdean.org.uk/
Adi Solutions https://www.groupadi.com/
Conservation by design http://www.cxdglobal.com/home.aspx?pagename=home
Conservation resources https://www.conservation-resources.co.uk/
Preservation equipment ltd https://www.preservationequipment.com/
Transportation & Installation Companies
Crown fine art https://www.crownfineart.com/en-us/
Universal Pallets https://www.universalpallets.com/2018/01/ultimate-guide-pallet-markings/
Wood Pallet specifications https://www.gov.uk/wood-packaging-import-export