How to keep a shed warm without a heater this winter

A grey garden shed with pots of lavender

(Image credit: Future PLC/Polly Eltes)

Jump to category:

1. Insulate
2. Seal gaps
3. Utilise thermal mass
4. Implement compost heating
5. Craft a DIY solar window heater

published 4 January 2024

Whatever you use your garden shed or greenhouse for this time of year, whether that’s storage or growing seedlings, you might be wondering how to keep a shed warm.

With the rise of energy prices owing to the new January energy price cap, most of us think twice before turning the heating on even at home. Let alone heating a garden shed or a greenhouse.

But luckily, there are more budget-friendly ways to keep these extensions of your garden warm throughout the winter months. So if you are looking for some alternative heating garden shed ideas, then you’ve come to the right place as we’ve found 5 methods for staying warm that come highly recommended by gardening experts.

How to keep a shed warm

‘Forget cranking up the heat! Keeping your shed toasty in winter doesn't have to drain your wallet or the planet,’ starts Sam Jenkinson, garden building expert at shed manufacturer, Tiger Sheds.

Steve Chilton, garden expert at LeisureBench, continues, ‘Keeping a shed or greenhouse warm on a budget without the use of heating can be achieved through various cost-effective methods, although you aren't guaranteed success.’

‘There's a higher chance of plants not growing properly if they require warm temperatures, due to the fact that chances are higher that there'll be less even heating of the greenhouse/shed,’ he warns. This is something to keep in mind when considering these DIY greenhouse ideas.

Steve Chilton

Steve is a passionate and knowledgeable garden expert with several years of experience within the field. As the director of LeisureBench, an industry-leading garden furniture company, Steve has developed strong expertise for all things nature and plants.

1. Insulate

Similarly to insulating your home, you can also insulate the walls of your shed or greenhouse.

‘Adding insulation to the walls, floor, and ceiling of your shed will significantly reduce heat loss,’ Sam says. ‘Consider affordable options like foam boards, thick roofing felt, EPDM roofing, cabin shingles, reflective bubble wrap, or blankets.’

He adds, ‘Even the earth can steal your heat. Counter it with rugs or carpets that insulate and add a splash of personality to your haven.’

Where to get insulation materials:

A greenhouse with plants and storing garden tools

2. Seal gaps

Sealing any gaps is key for any shed or greenhouse ideas to ensure warm air stays in and the cold stays out.

‘Seal any gaps. Make sure the doors and windows are well-sealed to prevent heat loss,’ says Petar Ivanov, gardening expert at Fantastic Gardeners.

Sam adds, ‘Block drafts around windows, doors, and any cracks or gaps in the shed walls to prevent cold air from leaking in.’

Where to get window and door sealants:

A wooden garden shed with a table filled with potted plants

Petar Ivanov

Petar Ivanov is one of the company's top-performing experts and manages over six teams of gardeners, delivering stunning landscape results and fostering a deep connection with nature through his work.

3. Utilise thermal mass

Place thermal mass, i.e. water-filled containers inside, which will absorb and radiate heat.

‘Install a thermal mass such as a water barrel or a large stone to absorb and store heat during the day and release it at night,’ explains Jack Sutcliffe, gardening expert and co-founder of Power Sheds.

Where to get water barrels:

A greenhouse with a path and large plant pots next to it

4. Implement compost heating

Why not make your waste do some extra work? It’s free after all.

‘Decomposing organic matter generates heat and you can benefit from this by placing a compost bin inside,’ Petar suggests.

Where to get compost bins:

5. Craft a DIY solar window heater

If you’re looking to get crafty, then this solar window heater is a pretty easy DIY project that could help you harvest the heat of the sun to warm up your shed or greenhouse.

‘Embrace the sun's power! Build a DIY solar window heater with black-painted beer cans, plywood, and an old window. It's like magic: the cans soak up solar rays, warm air rises, and a trusty fan blows it into your shed. It's green, potentially free, and a fun project for the crafty, but remember, its effectiveness can vary,’ Sam says.

Here’s to a warmer shed (or greenhouse) to keep your tools and plants nice and toasty.

Sara Hesikova has been a Content Editor at Ideal Home since June 2024, starting at the title as a News Writer in July 2023. She is now also the Ideal Home Certified Expert in Training on Furniture, and so far has tested 80 different sofas.

Graduating from London College of Fashion with a bachelor’s degree in fashion journalism in 2016, she got her start in niche fashion and lifestyle magazines like Glass and Alvar as a writer and editor before making the leap into interiors, working with the likes of 91 Magazine and copywriting for luxury bed linen brand Yves Delorme among others.

5 budget-friendly ways to keep your shed and greenhouse warm this winter without a heater