Storing Leather Projects: How to Avoid Mould and Cracking

You have spent hours cutting, stitching, and finishing a piece of leather – perhaps a hand-stitched wallet, a belt, or a bag – and the last thing you want is to pull it out of storage months later to find it covered in white fuzz or cracked along the grain. Unfortunately, improper storage is one of the most common ways that leather craftspeople, particularly beginners, ruin their work. The good news is that with a little understanding of how leather behaves and some straightforward precautions, your projects can remain in excellent condition for years.

This guide covers everything you need to know about storing leather projects correctly, from the basic science of why leather deteriorates, to practical steps you can take today in a typical British home – whether you live in a damp flat in Manchester, a cottage in rural Wales, or a terraced house in South London.

Understanding Why Leather Deteriorates in Storage

Leather is a natural material. It comes from animal hide that has been tanned – treated with either vegetable tannins, chrome salts, or other agents – to preserve and stabilise it. Despite that processing, leather retains an organic quality that makes it sensitive to its environment. Two main threats affect leather in storage: mould growth and desiccation (drying out and cracking).

Mould thrives in conditions where moisture is present and air circulation is poor. The UK climate does not help matters here. Britain’s famously damp weather, particularly in autumn and winter, means that humidity levels inside homes can fluctuate considerably. Mould spores are present in virtually every indoor environment; they only need moisture and a food source – such as the natural oils and fats remaining in leather – to begin colonising. Once mould takes hold, it can stain the surface permanently and begin breaking down the leather fibres themselves.

Cracking, on the other hand, happens when leather loses its natural moisture and oils. This can occur in heated rooms during winter, particularly in homes with central heating running for long stretches. As the leather dries out, it becomes rigid and eventually the surface fibres fracture. This is especially common with vegetable-tanned leather, which is popular among UK craft enthusiasts for its firm texture and tooling qualities.

The Ideal Storage Conditions for Leather

Getting the environment right is more important than any product you might apply. Leather is happiest in conditions that mimic a temperate, stable climate – not too damp, not too dry, and not subject to dramatic swings in either direction.

The recommended parameters for storing leather are as follows:

• Temperature: Between 15°C and 20°C is ideal. Avoid storing leather in lofts or garages where temperatures can drop sharply in winter or rise significantly in summer.
• Relative humidity: Between 45% and 55%. Below 40%, leather begins to dry out. Above 65%, mould becomes a serious risk.
• Light exposure: Keep leather away from direct sunlight and UV sources. Sunlight fades dye and accelerates drying.
• Air circulation: Some airflow is beneficial. Completely sealed, airless environments can trap moisture and encourage mould.

If you are unsure about the humidity in your storage area, an inexpensive hygrometer – available from most DIY stores including Screwfix or B&Q – will give you an accurate reading. They typically cost between £5 and £15 and are well worth the investment if you are storing multiple leather pieces.

Choosing the Right Storage Location in a British Home

Most British homes present specific challenges for leather storage. Older properties in particular can suffer from cold walls, rising damp, and poor insulation. Here is a practical assessment of common storage locations:

• Lofts: Generally unsuitable. Temperature extremes and humidity fluctuations are common, and condensation can form on cold surfaces.
• Garages: Poor choice for finished leather pieces. Unheated garages are damp in winter and hot in summer. Raw hides or tools in sealed containers may fare better here, but finished projects should be kept elsewhere.
• Under stairs cupboards: Can work well if the area is dry. Check for cold walls adjacent to external brickwork, which can cause condensation.
• Wardrobes in bedrooms: Often one of the best options. Bedroom temperatures tend to be relatively stable and dry. Ensure the wardrobe is not against an external wall with no insulation.
• Spare rooms: Acceptable if the room is heated occasionally. Unheated rooms in winter can drop to low temperatures and build up moisture.

The key principle is to choose somewhere with a consistent, moderate environment. Wherever your instinct is to store wine or instruments – those same conditions generally suit leather well.

How to Prepare Leather Projects Before Storage

Storing leather correctly begins before it goes into the cupboard. Preparation is essential, particularly for finished projects that may have accumulated dust, surface oils from handling, or residual moisture from a recent conditioning session.

1. Clean the surface. Use a damp (not wet) cloth to gently remove dust and surface grime. For finished leather, a dedicated leather cleaner such as those from Leather Master or Leather Honey is appropriate. Allow the piece to dry completely – never store leather that is even slightly damp.
2. Condition the leather. Apply a thin, even coat of a good leather conditioner. In the UK, products like Aussie Leather Conditioner, Carr & Day & Martin Leather Balsam, or Neatsfoot oil compound are all effective. Conditioning replaces the natural oils that keep leather supple and creates a degree of resistance to moisture ingress. Do not over-condition – a single thin coat is sufficient.
3. Allow full absorption. After conditioning, leave the piece for several hours – ideally overnight – to allow the conditioner to absorb fully before wrapping or packing the item.
4. Check all hardware. If your project has metal fittings such as buckles, rivets, or press studs, ensure they are dry and free from rust. Corroding metal can stain adjacent leather. A very light application of Renaissance Wax (widely used in UK conservation circles) on metal hardware can help prevent oxidation.
5. Stuff hollow items. Bags, pouches, and sheaths should be stuffed with acid-free tissue paper to help them retain their shape during storage. Avoid newspaper, which can transfer ink and acidity to the leather surface.

The Best Materials for Wrapping and Containing Leather

What you wrap leather in matters considerably. Some common household materials are actively harmful to leather in storage.

Plastic bags and airtight plastic boxes are frequently used but are problematic for longer-term storage. While they protect against dust, they trap moisture and prevent any air exchange, creating exactly the humid, stagnant conditions that mould favours. If you must use a plastic container – for example, to protect against pests – place a small silica gel sachet inside to absorb excess moisture, and do not seal it completely.

The following materials are well-suited to wrapping leather pieces:

• Acid-free tissue paper: Ideal for wrapping finished pieces. It is breathable, does not react chemically with the leather, and provides a buffer against surface scratches. Available from conservation suppliers or online retailers.
• Unbleached cotton cloth: Old pillowcases or cotton sheets make excellent storage wraps. Cotton breathes well and will not trap moisture against the surface.
• Archival storage boxes: Cardboard boxes treated to be acid-free are suitable for long-term storage. These are available from specialist archival suppliers such as Conservation By Design, based in Bedford, or from online sources.
• Cotton canvas dust bags: Similar to what high-end bags come packaged in. These allow air circulation while keeping dust off. You can make your own using basic cotton fabric if you are handy with a needle and thread.

Avoid rubber bands, which can react with leather dyes and leave marks. Avoid wrapping items tightly in synthetic materials. If you are stacking multiple items, place acid-free tissue between each piece to prevent dye transfer and surface abrasion.

Comparison: Storage Methods at a Glance

Dealing with Humidity: Practical Solutions for UK Homes

Given that humidity is the primary enemy of stored leather in Britain, it is worth addressing this directly. During the wetter months – which in much of the UK can stretch from October through to April – indoor humidity levels can climb well above the safe threshold for leather storage.

If you do not have a dehumidifier, consider placing silica gel sachets near your stored leather. These are inexpensive, reusable, and widely available. You can tell when they need recharging because most modern sachets change colour; place them in an oven at a low temperature (around

On the opposite end of the scale, central heating can strip moisture from leather just as effectively as a humid environment can saturate it. British homes with gas boilers and radiators running through winter can create conditions that are surprisingly dry, particularly in rooms where the heating is on for long periods. If your leather begins to feel stiff or shows fine surface cracks, this is often a sign that it has dried out too much. A good quality leather conditioner applied with a soft cloth every few months will help maintain the natural oils in the hide and keep it supple. Avoid applying too much at once; a thin, even coat worked gently into the surface is far more effective than a heavy application left to sit.

Storage positioning also matters more than many people realise. Leather should not be stored flat under heavy objects, as sustained pressure can cause creasing and distortion that is difficult to reverse. Similarly, avoid storing pieces in direct contact with untreated wooden surfaces, as certain woods release acids over time that can stain and degrade the leather. Acid-free tissue paper or a clean cotton cloth makes a reliable barrier. If you are storing rolled leather, keep the roll loose rather than tight, and stand it upright where possible to avoid flat spots forming along the length.

Ventilation is the final piece of the puzzle. Even in a well-regulated environment, leather benefits from occasional exposure to fresh air. If your storage space is a cupboard or a sealed box, try to open it up every few weeks and allow air to circulate for a short while. This prevents any residual moisture from becoming trapped and discourages the conditions that mould spores need to take hold.

Storing leather properly does not require a great deal of specialist equipment or effort, but it does require consistency. A stable temperature, controlled humidity, appropriate conditioning, and sensible positioning will protect your work far more reliably than any single product or quick fix. Whether you are keeping a finished bag, a half-completed belt, or raw sides of hide awaiting their next project, the principles remain the same: keep it cool, keep it dry, keep it breathing, and check on it regularly. With a little attention, well-stored leather can remain in excellent condition for years.