Cheap Insulation Hacks to Make Your Heat Pump Work Better & Slash Bills

Quick Summary (TL;DR)

• You don't need a huge budget. Effective insulation for a heat pump can start with cheap, simple DIY hacks that make a immediate difference.

• Focus on the worst leaks first: Draughty doors/windows and an uninsulated loft are the biggest sources of heat loss and offer the best return on investment.

• Top Cheap Hacks: Thermal curtains (£25-£60), DIY draught-proofing (£10-£40), and topping up loft insulation yourself (£250-£400) are the most cost-effective starting points.

• Pair with smart controls: A smart thermostat (£150-£250) helps your heat pump run efficiently after you've stopped the heat from escaping.

Cheap Insulation Hacks to Make Your Heat Pump Work Better & Slash Bills

Feeling the draft? You're not alone. Many UK homeowners are excited about the potential of air source heat pumps but are rightly concerned about the cost of upgrading their home's insulation first.

The good news? You don't need to spend thousands upfront. While whole-home insulation is ideal, there are incredibly effective, budget-friendly tricks you can do yourself to dramatically reduce heat loss and ensure your heat pump runs efficiently, saving you money on your running costs from day one.

This guide walks you through the most cost-effective insulation hacks that deliver the biggest bang for your buck.

Why Insulation is Non-Negotiable for Heat Pumps

Think of your home like a leaky bucket. A heat pump is designed to fill it with a steady, gentle trickle of warm water (low-temperature heat). If the bucket is full of holes (draughts, poor insulation), the pump has to work non-stop just to keep it from emptying, burning through electricity.

Good insulation plugs those holes. It allows your heat pump to do what it does best: maintain a constant, comfortable temperature efficiently. Even small fixes can lead to significant improvements in comfort and cost savings.

The Top 4 Cheap Insulation Hacks for Heat Pump Owners

1. Thermal Curtains & Window Film: Your Secret Weapon

• The Problem: Windows, especially single-glazed or older double-glazed units, are a major source of heat loss. At night, they act like a radiator in reverse, sucking warmth out of your room.

• The Hack: Hang heavy, thermal-lined curtains. These create a pocket of insulating air between the cold glass and your room. For an even cheaper option, apply insulating window film—a clear plastic sheet that shrinks tight with a hairdryer to create an invisible secondary glazing layer.

• Cost: Curtains: £25–£60 per window | Window Film: £10-£20 per window

• Pro Tip: Close curtains at dusk to trap heat and open them during the day to let free solar warmth in.

2. Draught-Proofing: The Ultimate Quick Win

• The Problem: Cold air sneaking in under doors, through letterboxes, keyholes, and gaps in floorboards forces your heat pump to constantly reheat the same air.

• The Hack: It’s the easiest and cheapest fix on this list.

  
  

  • Doors: Fit brush-style draught excluders on the bottom, letterbox flaps, and keyhole covers. A classic "draught snake" is a cheap and effective solution.

  • Windows: Use self-adhesive foam or rubber seals around the opening edges of windows.

  • Floors: Seal gaps between floorboards and skirting with a flexible acrylic sealant.

  
  

• Cost: £10 - £40 for a whole home's worth of materials.

• Pro Tip: On a windy day, feel for draughts with the back of your hand; you'll be surprised where the cold air gets in!

3. DIY Loft Insulation Top-Up

• The Problem: Heat rises, and up to 25% of your home's heat can escape through an uninsulated or under-insulated loft.

• The Hack: Topping up your loft insulation is one of the most effective DIY jobs. The recommended depth is 270-300mm. If your existing insulation is below that, simply roll out new mineral wool or sheep's wool insulation rolls perpendicular to the old layer.

• Cost: £250–£400 for a typical semi-detached house (materials only).

• Pro Tip: Wear a mask, gloves, and long sleeves when handling insulation. Be careful not to block any eaves ventilation to prevent condensation.

4. Smart Thermostat: The Brain for Your Heat Pump

• The Problem: Heat pumps are most efficient when running consistently. An old-fashioned thermostat can cause inefficient on/off cycling.

• The Hack: A smart thermostat optimizes your heat pump's schedule. Many models feature weather compensation and geofencing (turning down the heat when you leave) and learn how quickly your home heats up, preventing energy waste.

• Cost: £150–£250 (plus potential installation).

• Pro Tip: Ensure the smart thermostat you choose is fully compatible with heat pumps to access advanced features like weather compensation.

Insulation Hack	Approx. Cost	Potential Annual Saving	DIY Difficulty	Best For
Draught-Proofing	£10 - £40	Up to 10% on bills	Easy	Stopping immediate cold air influx
Thermal Curtains	£25 - £60 per window	Reduce window heat loss by 15%	Easy	Night-time insulation for rooms
DIY Loft Top-Up	£250 - £400	15-20% on heating bills	Medium	The single biggest impact for the price
Smart Thermostat	£150 - £250	8-12% on bills	Easy-Medium	Optimizing heating schedules & efficiency

About Air Source Company

At Air Source Company, we believe everyone should be able to afford a warm, energy-efficient home. As MCS-certified heat pump experts across the UK, we don't just install; we advise. We provide honest, practical guidance on cost-effective measures like these to ensure your heat pump journey is successful and affordable, often helping clients access grants like the Boiler Upgrade Scheme to offset the cost of both the pump and vital insulation upgrades.

Real Homeowner Story: "The Draught Snake Made All The Difference"

"We had our heat pump installed but the hallway was always freezing. An Air Source Company engineer pointed out the giant gap under our front door during our annual service. He suggested a simple £15 draught excluder. I was sceptical, but we bought one that same day. The difference was unbelievable! The hallway now holds its heat and our heat pump doesn't kick in nearly as often. It just shows you don't always need to spend big to save big."— Sarah K., Homeowner in Bristol

Ready to stop draughts and start saving?

You don't have to choose between comfort and cost. Start with these simple hacks today and feel the difference tonight.

👉 For bigger projects, get expert advice! Book a Free Home Insulation Assessment with Air Source Company.

Our experts can identify the most cost-effective insulation opportunities for your specific home and even help you understand if you qualify for government funding. Make your heat pump investment work smarter, not harder.

Frequently Asked Question(FAQ's)

What is the cheapest way to insulate a house for a heat pump?

The absolute cheapest way is draught-proofing. Sealing gaps around doors, windows, and floorboards with excluders, seals, and caulk can cost under £40 for a whole house and immediately prevents cold air from entering, reducing the workload on your heat pump.

Is loft insulation worth it for a heat pump?

Yes, loft insulation is one of the most effective and worthwhile upgrades for a heat pump. Since heat rises, an uninsulated loft can account for 25% of your heat loss. Adding or topping up loft insulation is a relatively low-cost DIY project that can reduce your heating bills by 15-20%, allowing your heat pump to run much more efficiently.

Can I install insulation myself before a heat pump installation?

Yes, many insulation projects are perfect for DIY. Draught-proofing, hanging thermal curtains, and even topping up loft insulation are all achievable for a competent DIYer. These improvements will make your home ready for a heat pump and can be done gradually to spread the cost.

Do thermal curtains really work?

Yes, thermal curtains are highly effective at reducing heat loss through windows. Their thick, lined fabric creates a barrier that traps a layer of insulating air between the cold glass and your room, reducing convective heat loss. Closing them at night can significantly improve a room's warmth.

Will these cheap hacks make a noticeable difference?

Absolutely. While full insulation is best, cheap hacks like draught excluders and thermal curtains address the biggest points of immediate heat loss. You will likely notice fewer cold draughts, rooms that feel warmer, and a heat pump that doesn't need to run as frequently, leading to lower energy bills.