Finding mould on curtains can feel particularly frustrating.
Curtains sit in plain sight, they absorb moisture easily, and once mould appears, it often comes back even after cleaning. Many worry that removing mould will ruin the fabric, fade colours, or weaken fibres, especially with lined or delicate curtains.
The good news is that mould can often be removed safely at home, as long as the right steps are followed.
This guide explains why curtains become mouldy, how to prepare them properly, which cleaning methods suit different fabrics, and how to prevent the problem from returning.
It is the same advice our team at Home Energy Save GB often share during home surveys when mould problems keep reappearing around windows.
What Causes Mould to Build Up on Curtains
Curtains are especially vulnerable to mould because they are often positioned directly against cold surfaces such as windows. When warm indoor air meets cold glass, condensation forms, and that moisture transfers straight onto the fabric. Over time, this creates the damp conditions that mould needs to grow.
In homes already dealing with wider mould problems, curtains tend to act like moisture sponges. They absorb humidity from the room and dry slowly, particularly during colder months when windows stay closed.
Where condensation forms regularly, surface cleaning helps temporarily, but addressing the wider mould problems within the property often makes the real difference.
Common causes include:
- Poor ventilation that traps moist air indoors
- Damp or cold window sills behind curtains
- Night-time condensation forming on glass
- High humidity from cooking, bathing, or drying clothes
If these conditions remain, cleaning alone will not solve the issue long term, which is why prevention matters as much as removal.
How to Prepare Curtains Before Cleaning
Preparation is an important step when learning how to get mould out of curtains without damaging the fabric. Mould spores can spread easily, so care at this stage helps protect both the fabric and indoor air quality.
Start by taking the curtains down carefully and moving them outside if possible. Wear gloves and, if mould coverage is heavy, a simple face covering to avoid breathing in spores. Gently shake the curtains outdoors to remove loose mould particles before any washing begins.
Next, check the care label. This tells you whether the fabric can be machine-washed, hand-washed, or requires professional cleaning. Ignoring these instructions increases the risk of shrinkage, colour loss, or weakened stitching.
It also helps to gather supplies in advance:
- Gloves and a soft brush
- White vinegar or baking soda
- Mild detergent
- A bucket or basin for soaking
- Clean towels for drying
Being prepared reduces rushed decisions that often lead to fabric damage.
Cleaning Methods for Different Fabric Types
Curtain fabrics vary widely, so one method does not suit all. Always test any cleaning solution on a small, hidden area first and wait for it to dry before continuing.
Cotton or linen curtains
These natural fabrics usually tolerate gentle hand washing well. Soaking in warm water with white vinegar or a borax solution helps kill mould spores without harming fibres. After soaking, wash with mild detergent and rinse thoroughly.
Synthetic fabrics
Polyester and blended curtains are often machine washable. Use a low-temperature cycle with a gentle detergent. Adding baking soda to the wash can help lift mould stains while remaining fabric-safe.
Delicate or expensive curtains
Silk, velvet, or lined curtains require extra care. Home treatments risk watermarks and fabric distortion. In these cases, dry cleaning or a professional service is the safest option.
Trying to scrub aggressively or use harsh chemicals increases the chance of permanent damage, so patience matters. If mould staining returns quickly after cleaning, it may point to an underlying damp issue rather than a fabric problem. In these cases, advice from an accredited damp specialist, such as Home Energy Save GB, can prevent repeated damage to furnishings.
Safe Products to Use When Treating Mould
Choosing the right product plays a big role in removing mould without damaging fabric. Many effective options are already found in most homes.
White vinegar works well because it kills mould spores rather than just bleaching stains. Baking soda helps lift marks and neutralise odours. Borax solutions are effective on heavier mould, particularly on washable fabrics.
Mould-specific sprays designed for textiles can also be useful, as long as they are non-bleach-based. Always check labels carefully and follow instructions.
Bleach is best avoided unless the care label clearly allows it. Bleach can weaken fibres, cause yellowing, and leave curtains more prone to future mould growth.
How to Dry Curtains Properly After Cleaning
Drying curtains thoroughly is just as important as cleaning them. Damp fabric encourages mould to return, sometimes within days.
Outdoor drying is ideal when the weather allows. Fresh air and sunlight help kill remaining spores naturally. Hang curtains fully open rather than folded to allow even airflow.
If outdoor drying is not possible, use clean towels to absorb excess moisture before hanging curtains indoors near a heat source. Some synthetic curtains can be tumble-dried on a low heat setting, but only if the care label confirms this is safe.
Curtains should feel completely dry before rehanging. Even slight dampness can restart mould growth once they are back against cold windows.
Ways to Stop Mould Returning on Curtains
Preventing mould on curtains relies on controlling moisture and improving airflow around windows. Small daily habits make a noticeable difference over time.
Helpful steps include:
- Opening windows briefly each day to refresh indoor air
- Using extractor fans during cooking and bathing
- Wiping down window frames and sills where condensation forms
- Using a dehumidifier during colder months
- Pulling curtains back from windows during the day to allow airflow
If mould keeps returning despite these steps, there may be a deeper issue with ventilation, insulation, or damp within the property. In those situations, professional guidance helps identify the root cause rather than treating symptoms alone.
Home Energy Save GB works with accredited fitters who assess both visible mould and the underlying moisture source, so solutions are based on evidence rather than guesswork. If you would like advice tailored to your home, you can contact us to discuss your options.
