If your home is feeling a little cramped, your first instinct might be to start decluttering or buy another storage solution. But before you spend money on extra furniture, it could be worth taking a closer look at the space you already have.According to professional organiser Caroline Caron Dhaouadi, founder of Homefulness, most homes are packed with untapped storage potential hiding in plain sight. From forgotten vertical spaces to awkward corners that rarely get a second glance, there are countless opportunities to create extra room without knocking down walls or embarking on a costly renovation.In fact, some of the easiest storage wins are also the most overlooked. 'Vertical wall space and the backs of doors are the easiest wins – a few well-placed hooks, rails or over-door racks cost very little, take minutes to fit and instantly create storage where there was none,' says Dhaouadi.For homeowners looking to maximise every inch, she also points to the tops of wardrobes and kitchen cupboards as offering some of the biggest hidden storage potential, particularly when organised with pull-out baskets or labelled storage boxes.Here are the 10 underused areas of your home that could become valuable storage space – from forgotten under-stairs cupboards to the vertical wall space experts say we're all overlooking.1. The under-stairs cupboardBazyl Storage Baskets (Set of 3), £28.95, SklumFor many households, the under-stairs cupboard becomes a catch-all space where random items disappear and are rarely seen again. Shoes, reusable bags, cleaning products and forgotten DIY supplies often end up piled together in an unruly heap.'Usually a black hole of odd shoes and carrier bags,' says Dhaouadi. 'It's awkwardly shaped, so people give up on it – but with a few shelves or pull-out units it becomes brilliant storage for the vacuum, cleaning supplies, shoes, tools or recycling.'Adding shelving that follows the angle of the stairs or installing pull-out baskets can transform this often-chaotic area into one of the most practical storage zones in the house.2. The tops of wardrobes and kitchen cupboardsSeagrass Storage Basket, from £24.99, H&MOut of sight often means out of mind, which is exactly why the space above wardrobes and kitchen cabinets is so frequently wasted.'This is the most wasted space in most homes,' says Dhaouadi. 'It's so high and so deep that anything put up there is lost forever – you simply can't see or reach the back.'The solution is organisation rather than simply piling things higher.'The trick is pull-out baskets or labelled boxes you can lift down as a unit; without them, you only ever use the front few inches. With them, you use the full depth.'These elevated spots are ideal for storing suitcases, seasonal decorations, spare bedding, winter coats and appliances that only come out occasionally.3. Vertical wall space Teak Mug Shelf, £75, Cox & CoxWhen thinking about storage, most of us focus on floor space. However, our walls often offer enormous untapped potential.'Empty walls are constantly overlooked because we think in terms of furniture that sits on the floor,' Dhaouadi explains.Shelving, hooks, pegboards and wall-mounted rails can dramatically increase storage without making a room feel crowded.'Shelving, rails, pegboards and hooks that go up the wall – especially above eye level – add huge capacity without taking a single inch of floor space, which also keeps a room feeling calm and larger.'This approach works particularly well in kitchens, utility rooms, home offices and children's bedrooms where everyday items can be stored vertically rather than spread across surfaces.4. The backs of doors Natural Rib Over Door Hooks (Set of 2), £16, NextDoors are often viewed simply as a way to move between rooms, but they can also provide valuable storage opportunities.'Every internal door, cupboard door and wardrobe door is a free vertical surface,' says Dhaouadi.Simple over-door organisers can hold everything from shoes and accessories to toiletries and cleaning products.'Over-door racks and hooks are perfect for shoes, accessories, cleaning bottles, wrapping paper or toiletries.'Best of all, they're inexpensive, easy to install and don't require any drilling in many cases.5. Under the bed Stripe Underbed Storage Bag, £14, DunelmMost people know the space under the bed can be useful, but Dhaouadi believes many households aren't making the most of it.'Most people store a little here but could store far more,' she says.Instead of allowing the area to become a dust trap, invest in purpose-made storage boxes or vacuum-sealed bags.'Shallow wheeled boxes or vacuum bags make it ideal for bedding, shoes and seasonal clothing.'It's particularly useful for bulky items that don't need to be accessed daily but still need a home.6. The insides of cupboard doors Self-Adhesive Storage Box (Set of 2), £12.99, AmazonWhile many homeowners make use of cabinet interiors, the backs of cupboard doors are often completely ignored.Yet these slim surfaces can be surprisingly useful.'The back of a kitchen or bathroom cabinet door holds chopping boards, foil and cling film, or daily toiletries, on slim adhesive racks,' says Dhaouadi.By using narrow organisers, you can free up shelf space while keeping frequently used items close at hand.7. Alcoves and awkward corners Uganda Marble Wall Shelf, £42.95, SklumThose recesses and unusual corners that can feel difficult to furnish are often ideal candidates for clever storage.Alcoves and awkward corners may seem problematic, but Dhaouadi sees them as an opportunity rather than a challenge.'The recesses either side of a chimney breast are prime spots for built-in or floating shelving and cope beautifully with books, baskets and display storage.'Even a few simple floating shelves can transform an otherwise unused area into a practical and attractive feature.8. Bedroom headboards and bedside zones Wall Shelf, £34.99, H&MTraditional bedside tables can take up valuable floor space, especially in smaller bedrooms.Instead, Dhaouadi recommends thinking more creatively about the area around your bed.'A headboard with built-in shelving, or wall-mounted shelves beside the bed, frees up the floor and replaces bulky bedside tables.'This approach provides a place for books, glasses, charging cables and other essentials while helping the room feel less cluttered.9. The hallway above coat-hook height Fern 4 Basket Hook Unit, £170, Sustainable FurnitureHallways are often among the hardest-working areas of a home, yet much of the available wall space goes unused.'The strip of wall above the coats usually sits empty,' Dhaouadi points out.Adding a simple shelf above existing coat hooks can create valuable extra storage.'A shelf there holds hats, gloves and post.'It's a straightforward upgrade that helps keep everyday essentials organised without taking up precious floor space in what is often a narrow area.10. Utility and under-sink areas Kitchen Under Sink Storage Organiser, £18.99, AmazonDeep cupboards beneath sinks can quickly become cluttered and difficult to navigate.Cleaning products, spare sponges and household essentials often end up stacked behind one another, making it impossible to see what's actually there.'Tiered shelving and stacking drawers turn these deep, dark cupboards into genuinely usable space rather than a jumble at the front,' says Dhaouadi.Simple organisers can make a dramatic difference, helping you maximise every inch while making items easier to find.