Jennifer Sheahan: The interior design mistakes to avoid

But it can still be costly, and when you’re working to a fixed budget you want to avoid every unnecessary expense possible. The good news is that many of these common mistakes are easy to avoid once you know what to look out for. 

Here are some of the most frequent errors people make when renovating their homes — and how to sidestep them.

MEASUREMENTS

This one is so common I sometimes feel like personally delivering a measuring tape to every home in Ireland so that nobody has any excuse ever again. Measure everything three times. 

Measure properly — don’t forget to take skirting boards into account — for instance, when measuring the width of the room.

Accuracy

Ideally, invest in a laser measure to be certain you have an accurate measurement. Keep note of the measurements on your phone, and bring a measuring tape with you every time you go interior shopping so that you can be sure you don’t come home with something that just doesn’t quite fit.

When shopping for large items — for instance, a couch, a bed, or a dining table — I recommend using masking tape to create an outline of the item on your floor so that you can be sure it will fit properly.

LIGHTING

Lighting is often overlooked in interior design but it is transformative. 

Installing runway-style strips of spotlights in the ceiling, or relying on a single overhead light, are two of the most common mistakes people make. This can leave a room feeling harsh and uninviting or can leave some areas underlit.

Layers

A well-lit room should have three layers of lighting, including ambient lighting (such as wall sconces or ceiling fixtures), task lighting (like reading lamps or under-cabinet lights in the kitchen), and accent lighting (such as decorative lamps or picture lights). 

Consider how you use the space to decide what kind of lighting is required and install dimmers everywhere possible to create flexibility throughout the day. Warm-toned bulbs (2400 Kelvins and below) are great to make a room feel cosy and warm.

WINDOWS

Curtains and blinds can do wonders for a room — when they’re hung correctly. A common mistake is mounting them too low, which can make ceilings appear lower and windows smaller than they actually are.

To create the illusion of height, mount curtain rods as close to the ceiling as possible rather than just above the window frame. Ideally, curtains should just kiss the floor or puddle slightly for a more luxurious look.

Similarly, when it comes to blinds, inside-mounted blinds should fit snugly within the window frame, while outside-mounted blinds should extend well beyond the window edges to maximize light control and create a grander effect.

PAINT

Choosing a paint colour can feel overwhelming, and many people make the mistake of picking a colour straight from a tiny swatch and painting an entire room before realizing it doesn’t look quite right. Natural and artificial lighting can significantly affect how a colour appears in your space, so it’s essential to test samples first.

Paint a few large swatches on different walls and observe them at different times of the day before committing to a final choice. If you can’t paint on the wall, paint a large sheet of white paper and hang it in the room for at least a full day so you can see how it looks in all lighting conditions. 

Remember that undertones matter — a seemingly neutral grey might have blue, green, or purple undertones that become more noticeable once applied to a large surface.

ARTWORK

Hanging artwork too high or too low is a common mistake that can throw off the entire balance of a room. 

As a general guideline, artwork should be hung so that the centre of the piece is at eye level — roughly 145cm–150cm from the floor. 

If you’re creating a gallery wall, start with the largest piece at eye level and arrange the others around it in a way that feels natural.

Size

Another mistake is choosing artwork that is too small for the space. A single small print floating on a large wall can look lost and insignificant. 

If you have a big wall to fill, go for a larger piece or a series of smaller pieces grouped together for impact. The rule of thumb is that artwork should fill 60%-70% of the available wall space.

RUGS

A rug can tie a room together beautifully — but only if it’s the right size. 

Too often, people choose rugs that are too small, which has the unexpected effect of making the room feel shrunken and uncomfortable.

Size

The general rule of thumb is that a rug should be large enough for at least the front legs of all the surrounding furniture to sit on it. In a living room — for instance, the rug should extend under the sofa and chairs rather than floating awkwardly in the middle of the floor. 

If you’re unsure, err on the side of bigger rather than smaller. You can also layer rugs to create the right size for your space.

FURNITURE

It’s tempting to push all your furniture against the walls in an attempt to create more space in the middle of the room. However, this often has the opposite effect, making a space feel disconnected and cavernous rather than cosy and inviting.

Instead, try pulling furniture away from the walls to create more intimate seating areas. This is particularly important in living rooms, where floating a sofa and chairs around a central coffee table can make the space feel more balanced and functional. 

If your room is small, even a couple of centimetres away from the wall can make a big difference.