Joisties | Steel Joists
Joisties were one of those wonderfully practical ideas that did exactly what they were meant to do. They made underfloor insulation easier to install, helped hold it neatly in place and solved thermal bridging which is a very real problem for DIYers working under steel framed floors.
The trouble is, they were also expensive to manufacture.
So, rather than keep selling something that made the solution out of reach of many, we’ve taken Joisties back into R&D. We’re working on a better way to achieve the same result, without the same manufacturing cost.
They’re not gone forever. They’re just back in the workshop. Hang in there. We’re on it.
🚛 Delivery direct to your doorstep
🗓️ Availability: Back in R&D
🏅 70 years product warranty
Pairs well with
Product details
Description
Specification
How To Install
Delivery
FAQ
Frequently asked questions
Can I insulate my floor if I have steel joists instead of timber?
Yes—you absolutely can! That’s what Joisties were made for. Traditional underfloor insulation is tricky with steel joists because you can’t staple into them. Joisties are a clever, system that deals with the thermal bridge from steel joists holds insulation batts firmly in place—no drilling or frustration.
Do I need any special tools to install insulation with Joisties?
Not really—just your standard DIY gear and a Joisties Fitting Tool, which helps you align and install the Joisties easily. Once they’re in, you simply slide the insulation batts into place. It’s a smart, DIY-friendly solution for steel-framed homes.
Is underfloor insulation really worth the effort?
Yes! Up to 20% of your home’s heat can escape through the floor. Underfloor insulation helps keep you warmer in winter, cooler in summer, and significantly reduces your heating and cooling costs. It’s one of the smartest upgrades you can make—especially when you’ve got the right tools to make it easy.
Perfect for
🔹 Keeping Your Home Comfy – Helps keep your house warm in winter and cool in summer
🔹 Saving Money – Stops heat and cool from escaping, so you don’t need to use your heater or air conditioner as much
🔹 Soft and Safe – Made from soft, non-itchy polyester insulation that won’t cause allergies
🔹 Long-Lasting Protection – Strong and stays in place. Guaranteed to work for you for 70 years