Saturday, 2 October 2010

Conserving Your Books

The wide range of books found in collections can include modern paperbacks, cloth-bound hardbacks, leather bindings or even vellum-covered books. Books come in all shapes and sizes and may be rare or ephemeral. Some are in everyday use, whilst others may seldom be looked at. They may have considerable personal or financial value to you as owner, collector or curator.

Books are made from a variety of materials, most of which are natural products. The paper, boards and thread of a book are all composed of cellulose, a plant material. The covers can be made from a wider variety, including skin products (leather, vellum or parchment), textiles or plastic. Some of these materials are of good, durable quality but others have inherent weaknesses and tend to degrade, especially if their storage or display conditions are poor or if they have been used a lot.

What can go wrong?

Damage is related to four main factors: what the book is made of, how and where it has been stored, the construction of the book, and the degree of use the book has been subject to.

Specialist book conservators know about the manufacture and construction of books of all periods and materials. As well as carrying out treatments on individual books, they can help you identify which items are at risk, and advise you on the best ways of protecting your collection and retaining its value for the future.

These are the kind of problems you can detect yourself:

Poor-quality paper may become brittle and yellow. This is usually due to impurities in the cellulose, but it can be made worse by poor storage conditions.

Dust collecting on the top edges of books may lead to discolouration and encourage mould growth.
Paper and other organic materials (such as leather) react to changes in the moisture content of surrounding air. The edges of the pages may cockle if the surrounding environment is too damp and conversely, books can also become stiff and brittle if the environment is too dry. A fluctuating environment will stress the structure of a book and cause damage, for example tears and splits at the joints where the book covers join the spine.

Damp and mould provide a favourable environment for insects which eat cellulose: certain insects can bore right through books.
Large books such as family bibles are often poorly made, and so heavy that their boards can split away from the book at the joints.
Where pages become loose, they are easily creased, torn and dog-eared.
Leather bindings can become sticky and will attract dirt if oils and leather dressings have been over-applied.
Leather can also become dry and crumbly. ‘Red rot’ (where the leather deteriorates to a fine red dust) results from the way the leather was tanned. Books affected by this condition can be boxed or wrapped in acid-free paper to prevent marking of surrounding volumes.

What you can do

Good handling and storage are the best ways to avoid damage. Books are complicated mechanical objects and the way in which they are opened and closed, and manipulated during use influences how long they last.


Always open a book carefully, without forcing, since the materials it is made from may have become weak over time. Some old books may not open much beyond 90˚. Placing books face down on a flat surface will break the binding.

The paper may be weak or damaged, so turn the pages carefully to avoid tearing. Be aware that dirt and oil from your skin can damage and stain paper. Gloves are sometimes recommended for handling bindings, particularly textile bindings or those with metal clasps, however, gloves can reduce your sensitivity to delicate papers so it is advisable to use clean, dry hands instead for turning pages.

Take care when removing and replacing books from shelves. Headbands are particularly prone to damage as they can be pulled off when removing a book.


A cool, dry and stable environment is ideal. Temperatures of 16-19˚C and a relative humidity of 45-60% are recommended. If it is difficult to achieve this within the home, try to achieve a stable environment with a relative humidity of less than 60%; above this, mould and insects can flourish. This normally means keeping books away from direct heat sources such as radiators, sources of moisture such as damp external walls, and avoiding storage in attics, garages or basements where temperature and humidity fluctuate, where pests may be a problem and where leaks and floods are relatively common.

Try to protect books from direct light, especially daylight which can be particularly damaging. Light damage is irreversible.

Store books neatly, upright on bookshelves and do not allow them to lean sideways and become distorted. If possible, books should not come into contact with unsealed wood which can release organic acid vapours. Line shelves with conservation board (acid-free) to avoid this problem.

Make sure that there is good air circulation, for example avoid pushing books to the back of a shelf. This will reduce the risk of condensation and mould developing.

Try to store books of a similar size next to each other so that the volumes are properly supported. Use book ends for support if necessary. Large books are best stored horizontally.

Avoid the temptation to pack the shelves tightly as this will make the books vulnerable to damage when you are removing and replacing them from the shelves.